ASE Technology Holding (ASX) 20-F 29 Mar 22 2021 FY Annual report (foreign) Financial data

Cover Page

Cover Page	12 Months Ended
	Dec. 31, 2021shares
Document Information [Line Items]
Document Type	20-F
Amendment Flag	false
Document Period End Date	Dec. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Trading Symbol	ASX
Entity Registrant Name	ASE Technology Holding Co., Ltd.
Entity Central Index Key	0001122411
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Shell Company	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding	4,408,018,732
Document Annual Report	true
Document Transition Report	false
Document Shell Company Report	false
Document Registration Statement	false
Title of 12(b) Security	Common Shares
Entity Interactive Data Current	Yes
Entity Voluntary Filers	No
Entity Address, Country	TW
ICFR Auditor Attestation Flag	true
Entity Address, Address Line One	26, Chin 3rd Road
Entity Address, Address Line Two	Nanzih District
Entity Address, City or Town	Kaohsiung
Entity File Number	001-16125
Entity Incorporation, State or Country Code	F5
Entity Address, Postal Zip Code	811
Document Accounting Standard	International Financial Reporting Standards
Security Exchange Name	NYSE
Auditor Name	Deloitte & Touche
Auditor Firm ID	1060
Auditor Location	Taipei, Taiwan
Business Contact [Member]
Document Information [Line Items]
Entity Address, Country	TW
Contact Personnel Name	Joseph Tung
Contact Personnel Email Address	ir@aseglobal.com
Contact Personnel Fax Number	882-2-2757-6121
Entity Address, Address Line One	Room 1901, No. 333, Section 1 Keelung Rd.
Entity Address, City or Town	Taipei
City Area Code	886-2
Local Phone Number	6636-5678
Entity Address, Postal Zip Code	110

Consolidated Balance Sheets

Consolidated Balance Sheets $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
CURRENT ASSETS
Cash and cash equivalents	$ 76,073,345	$ 2,742,370	$ 51,538,071
Financial assets at fair value through profit or loss - current	2,933,446	105,748	4,342,605
Contract assets - current	5,607,209	202,134	4,782,904
Trade receivables, net	115,462,210	4,162,300	91,833,989
Other receivables	13,732,607	495,047	3,693,936
Current tax assets	542,180	19,545	702,820
Inventories	67,832,981	2,445,313	48,590,434
Inventories related to real estate business	5,412,114	195,102	13,471,645
Other financial assets - current	140,857	5,078	551,655
Other current assets	4,620,779	166,575	4,578,783
Total current assets	292,357,728	10,539,212	224,086,842
NON-CURRENT ASSETS
Financial assets at fair value through profit or loss - non-current	2,502,834	90,225	2,180,978
Financial assets at fair value through other comprehensive income - non-current	2,019,812	72,812	1,741,134
Investments accounted for using the equity method	16,996,600	612,711	12,806,673
Property, plant and equipment	239,867,550	8,646,992	234,365,397
Right-of-use assets	10,680,262	385,013	8,741,807
Investment properties	22,144,787	798,298	12,538,083
Goodwill	52,072,413	1,877,160	52,709,053
Other intangible assets	24,563,707	885,498	27,711,771
Deferred tax assets	5,369,010	193,548	5,477,373
Other financial assets - non-current	1,416,123	51,050	530,345
Other non-current assets	3,275,073	118,063	1,263,188
Total non-current assets	380,908,171	13,731,370	360,065,802
Total assets	673,265,899	24,270,582	584,152,644
CURRENT LIABILITIES
Short-term borrowings	34,319,464	1,237,183	31,290,839
Financial liabilities at fair value through profit or loss - current	417,660	15,056	1,537,208
Financial liabilities for hedging - current	6,716,965	242,140	5,277,325
Trade payables	84,470,284	3,045,072	73,268,234
Other payables	46,696,900	1,683,378	39,415,623
Current tax liabilities	16,362,350	589,847	6,514,502
Lease liabilities - current	809,536	29,183	774,444
Current portion of bonds payable	9,902,710	356,983	6,999,951
Current portion of long-term borrowings	4,526,683	163,183	2,250,121
Other current liabilities	13,022,789	469,459	7,264,084
Total current liabilities	217,245,341	7,831,484	174,592,331
NON-CURRENT LIABILITIES
Financial liabilities for hedging - non-current	4,780,931	172,348	5,910,919
Bonds payable	42,364,627	1,527,204	49,253,603
Long-term borrowings	117,164,876	4,223,680	102,259,378
Deferred tax liabilities	7,590,197	273,619	7,121,027
Lease liabilities - non-current	6,590,348	237,576	5,101,386
Net defined benefit liabilities	5,864,071	211,394	6,466,794
Other non-current liabilities	3,494,448	125,971	1,710,090
Total non-current liabilities	187,849,498	6,771,792	177,823,197
Total liabilities	405,094,839	14,603,276	352,415,528
Share capital
Ordinary shares	44,034,146	1,587,388	43,385,311
Shares subscribed in advance	52,356	1,887	130,609
Total share capital	44,086,502	1,589,275	43,515,920
Capital surplus	143,693,168	5,179,999	139,767,550
Retained earnings
Legal reserve	6,300,198	227,116	3,901,384
Special reserve	9,569,027	344,954	10,847,697
Unappropriated earnings	69,712,555	2,513,070	30,084,965
Total retained earnings	85,581,780	3,085,140	44,834,046
Other equity	(12,246,443)	(441,472)	(10,043,302)
Treasury shares	(7,488,362)	(269,948)	(1,959,107)
Equity attributable to owners of the Company	253,626,645	9,142,994	216,115,107
NON-CONTROLLING INTERESTS	14,544,415	524,312	15,622,009
Total equity	268,171,060	9,667,306	231,737,116
TOTAL	$ 673,265,899	$ 24,270,582	$ 584,152,644

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)$ / shares	Dec. 31, 2021USD ($)$ / shares	Dec. 31, 2020TWD ($)$ / shares	Dec. 31, 2019TWD ($)$ / shares
Statement [LineItems]
OPERATING REVENUES	$ 569,997,133	$ 20,547,842	$ 476,978,710	$ 413,182,184
OPERATING COSTS	459,628,356	16,569,155	398,994,442	348,871,391
GROSS PROFIT	110,368,777	3,978,687	77,984,268	64,310,793
OPERATING EXPENSES
Selling and marketing expenses	6,386,763	230,237	5,605,464	5,751,168
General and administrative expenses	20,804,032	749,965	18,200,304	16,637,887
Research and development expenses	21,053,633	758,963	19,302,418	18,395,334
Total operating expenses	48,244,428	1,739,165	43,108,186	40,784,389
OTHER OPERATING INCOME AND EXPENSES, NET	1,189,829	42,892	502,492	(268,555)
PROFIT FROM OPERATIONS	63,314,178	2,282,414	35,378,574	23,257,849
NON-OPERATING INCOME AND EXPENSES
Other income	1,600,099	57,682	1,474,547	1,359,093
Other gains and losses	17,211,099	620,443	1,827,576	2,683,989
Finance costs	(2,831,307)	(102,066)	(3,459,511)	(4,203,395)
Share of the profit or loss of associates and joint ventures	899,700	32,433	547,612	182,275
Total non-operating income and expenses	16,879,591	608,492	390,224	21,962
PROFIT BEFORE INCOME TAX	80,193,769	2,890,906	35,768,798	23,279,811
INCOME TAX EXPENSE	17,943,772	646,856	7,116,898	5,011,246
PROFIT FOR THE YEAR	62,249,997	2,244,050	28,651,900	18,268,565
Items that will not be reclassified subsequently to profit or loss:
Remeasurement of defined benefit obligation	51,167	1,845	(594,778)	(365,262)
Unrealized gain (loss) on equity instruments at fair value through other comprehensive income	202,092	7,285	(166,239)	(216,121)
Share of other comprehensive income of associates and joint ventures	3,595,194	129,603	2,656,966	1,504,760
Income tax relating to items that will not be reclassified subsequently to profit or loss	(179,403)	(6,467)	(122,901)	(3,816)
Items that will not be reclassified subsequently to profit or loss	3,669,050	132,266	1,773,048	919,561
Items that may be reclassified subsequently to profit or loss:
Exchange differences on translating foreign operations	(4,094,565)	(147,605)	(831,784)	(5,202,145)
Unrealized gain (loss) on debt investments at fair value through other comprehensive income	63,722	2,297	(2,136)	(2,052)
Gain (loss) on hedging instruments	738,600	26,626	(574,824)
Share of other comprehensive income (loss) of associates and joint ventures	29,209	1,053	131,009	(85,975)
Items that may be reclassified subsequently to profit or loss	(3,263,034)	(117,629)	(1,277,735)	(5,290,172)
Other comprehensive income (loss) for the year, net of income tax	406,016	14,637	495,313	(4,370,611)
TOTAL COMPREHENSIVE INCOME FOR THE YEAR	62,656,013	2,258,687	29,147,213	13,897,954
NET PROFIT ATTRIBUTABLE TO:
Owners of the Company	60,150,167	2,168,353	26,970,580	17,060,591
Non-controlling interests	2,099,830	75,697	1,681,320	1,207,974
PROFIT FOR THE YEAR	62,249,997	2,244,050	28,651,900	18,268,565
TOTAL COMPREHENSIVE INCOME ATTRIBUTABLE TO:
Owners of the Company	60,630,154	2,185,657	27,440,726	13,122,185
Non-controlling interests	2,025,859	73,030	1,706,487	775,769
TOTAL COMPREHENSIVE INCOME FOR THE YEAR	$ 62,656,013	$ 2,258,687	$ 29,147,213	$ 13,897,954
EARNINGS PER SHARE
Basic | (per share)	$ 13.97	$ 0.50	$ 6.32	$ 4.01
Diluted | (per share)	13.54	0.49	6.17	3.91
American depositary shares [member]
EARNINGS PER SHARE
Basic | (per share)	27.94	1.01	12.65	8.02
Diluted | (per share)	$ 27.07	$ 0.98	$ 12.33	$ 7.82

Consolidated Statements of Chan

Consolidated Statements of Changes in Equity $ in Thousands, $ in Thousands	TWD ($)	USD ($)	Share capital [member]TWD ($)shares	Share capital [member]USD ($)shares	Capital surplus [member]TWD ($)	Capital surplus [member]USD ($)	Legal reserve [member]TWD ($)	Legal reserve [member]USD ($)	Special reserve [member]TWD ($)	Special reserve [member]USD ($)	Unappropriated earnings [member]TWD ($)	Unappropriated earnings [member]USD ($)	Retained earnings [member]TWD ($)	Retained earnings [member]USD ($)	Exchange differences on translating foreign operations [member]TWD ($)	Exchange differences on translating foreign operations [member]USD ($)	Unrealized gain (loss) on financial assets at fair value through other comprehensive income [member]TWD ($)	Unrealized gain (loss) on financial assets at fair value through other comprehensive income [member]USD ($)	Gain loss on hedging instrument [Member]TWD ($)	Gain loss on hedging instrument [Member]USD ($)	Other equity[member]TWD ($)	Other equity[member]USD ($)	Treasury shares [member]TWD ($)	Treasury shares [member]USD ($)	Equity Attributable to Owners of the Company [member]TWD ($)	Equity Attributable to Owners of the Company [member]USD ($)	Non-controlling interests [member]TWD ($)	Non-controlling interests [member]USD ($)	Unearned Employee Compensation [Member]TWD ($)	Unearned Employee Compensation [Member]USD ($)
Balance at January 1 (Adjusted Balance [member]) at Dec. 31, 2018	$ 219,027,922		$ 43,217,144		$ 143,276,664				$ 3,353,938		$ 20,403,477		$ 23,757,415		$ (5,888,574)		$ (1,015,107)				$ (6,903,681)		$ (1,959,107)		$ 201,388,435		$ 17,639,487
Balance at January 1 at Dec. 31, 2018			4,321,714												(5,888,574)												17,639,487
Appropriation of earnings
Legal reserve							$ 2,203,895				(2,203,895)
Special reserve									3,548,844		(3,548,844)
Cash dividends distributed by the Company	(10,806,454)										(10,806,454)		(10,806,454)												(10,806,454)
Change from investments in associates accounted for using the equity method	3,604				3,604																				3,604
Other changes in the capital surplus	1,070				1,070																				1,070
Net profit for the year	18,268,565										17,060,591		17,060,591												17,060,591		1,207,974
Other comprehensive income (loss) for the year, net of income tax	(4,370,611)										(280,461)		(280,461)		(4,874,110)		1,216,165				(3,657,945)				(3,938,406)		(432,205)
Total comprehensive income (loss)	13,897,954										16,780,130		16,780,130		(4,874,110)		1,216,165				(3,657,945)				13,122,185		775,769
Issue of ordinary shares for capital increase by cash	(10,806,454)						2,203,895		3,548,844		(16,559,193)		(10,806,454)												(10,806,454)
Cash dividends received by subsidiaries from the Company	182,354				182,354																				182,354
Disposal of interest in associates and joint ventures accounted for using the equity method	(73,884)				(75,276)						1,392		1,392												(73,884)
Differences between consideration and carrying amount arising from acquisition or disposal of subsidiaries	(7,114,703)				(2,779,613)																				(2,779,613)		(4,335,090)
Changes in percentage of ownership interest in subsidiaries	(3,977,486)				(1,960,167)																				(1,960,167)		(2,017,319)
Issue of ordinary shares under share-based payment arrangements	1,225,163		$ 88,143		1,137,020																				1,225,163
Issue of ordinary shares under share-based payment arrangements (Shares) | shares			8,814,000	8,814,000
Cash dividends distributed by subsidiaries	(360,245)																										(360,245)
Additional non-controlling interest arising on issue of employee share options by subsidiaries	797,017				(875,293)																				(875,293)		1,672,310
Disposal of investments in equity instruments at fair value through other comprehensive income											404,156		404,156				(404,156)				(404,156)
Balance at December 31 at Dec. 31, 2019	212,802,312		$ 43,305,287		138,910,363		2,203,895		6,902,782		21,029,962		30,136,639		(10,762,684)		(203,098)				(10,965,782)		(1,959,107)		199,427,400		13,374,912
Ending balance, shares at Dec. 31, 2019 | shares			4,330,528	4,330,528
Appropriation of earnings
Legal reserve							1,697,489				(1,697,489)
Special reserve									3,944,915		(3,944,915)
Cash dividends distributed by the Company	(8,668,331)										(8,668,331)		(8,668,331)												(8,668,331)
Change from investments in associates accounted for using the equity method	22,774				22,774																				22,774
Other changes in the capital surplus	1,608				1,608																				1,608
Net profit for the year	28,651,900										26,970,580		26,970,580												26,970,580		1,681,320
Other comprehensive income (loss) for the year, net of income tax	495,313										(469,748)		(469,748)		(879,255)		2,248,414		$ (429,265)		939,894				470,146		25,167
Total comprehensive income (loss)	29,147,213										26,500,832		26,500,832		(879,255)		2,248,414		(429,265)		939,894				27,440,726		1,706,487
Issue of ordinary shares for capital increase by cash	(8,668,331)						1,697,489		3,944,915		(14,310,735)		(8,668,331)												(8,668,331)
Cash dividends received by subsidiaries from the Company	145,741				145,741																				145,741
Disposal of interest in associates and joint ventures accounted for using the equity method	2,313				2,199						(980)		(980)				1,094		0		1,094				2,313
Differences between consideration and carrying amount arising from acquisition or disposal of subsidiaries	(129,942)				(13,502)																				(13,502)		(116,440)
Changes in percentage of ownership interest in subsidiaries	(4,128,788)				(780,533)						(2,760,175)		(2,760,175)												(3,540,708)		(588,080)
Issue of ordinary shares under share-based payment arrangements	1,799,425		$ 210,633		1,588,792																				1,799,425
Issue of ordinary shares under share-based payment arrangements (Shares) | shares			21,064,000	21,064,000
Cash dividends distributed by subsidiaries	(346,774)																										(346,774)
Additional non-controlling interest arising on issue of employee share options by subsidiaries	1,089,565				(109,892)						(392,447)		(392,447)												(502,339)		1,591,904
Disposal of investments in equity instruments at fair value through other comprehensive income											18,508		18,508				(18,508)				(18,508)
Balance at December 31 at Dec. 31, 2020	231,737,116		$ 43,515,920		139,767,550		3,901,384		10,847,697		30,084,965		44,834,046		(11,641,939)	$ (419,681)	2,027,902		(429,265)		(10,043,302)		(1,959,107)		216,115,107		15,622,009	$ 563,158
Ending balance, shares at Dec. 31, 2020 | shares			4,351,592	4,351,592
Appropriation of earnings
Legal reserve							2,398,814				(2,398,814)
Special reserve									(1,278,670)		1,278,670
Cash dividends distributed by the Company	(18,389,856)										(18,389,856)		(18,389,856)												(18,389,856)
Change from investments in associates accounted for using the equity method	(30,533)				(30,533)						450,054		450,054				(450,054)				(450,054)				(30,533)
Other changes in the capital surplus	1,633				1,633																				1,633
Net profit for the year	62,249,997	$ 2,244,050									60,150,167		60,150,167												60,150,167		2,099,830
Other comprehensive income (loss) for the year, net of income tax	406,016	14,637									25,842		25,842		(3,751,707)		3,654,754		551,098		454,145				479,987		(73,971)
Total comprehensive income (loss)	62,656,013	2,258,687									60,176,009		60,176,009		(3,751,707)		3,654,754		551,098		454,145				60,630,154		2,025,859
Buy-back of ordinary shares	(5,529,255)																						(5,529,255)		(5,529,255)
Issue of ordinary shares for capital increase by cash	(18,389,856)						2,398,814		(1,278,670)		(19,510,000)		(18,389,856)												(18,389,856)
Issue of convertible bonds by subsidiaries	393,199																										393,199
Cash dividends received by subsidiaries from the Company	305,737				305,737																				305,737
Changes in percentage of ownership interest in subsidiaries	(5,337,683)				(58,448)						(2,530,714)		(2,530,714)												(2,589,162)		(2,748,521)
Issue of ordinary shares under share-based payment arrangements	3,054,372		$ 570,582		3,648,781																(1,164,991)				3,054,372				$ (1,164,991)
Issue of ordinary shares under share-based payment arrangements (Shares) | shares			57,058,000	57,058,000
Cash dividends distributed by subsidiaries	(1,062,529)																										(1,062,529)
Additional non-controlling interest arising on issue of employee share options by subsidiaries	372,846				58,448																				58,448		314,398
Disposal of investments in equity instruments at fair value through other comprehensive income											1,042,241		1,042,241				(1,042,241)				(1,042,241)
Balance at December 31 at Dec. 31, 2021	$ 268,171,060	$ 9,667,306	$ 44,086,502	$ 1,589,275	$ 143,693,168	$ 5,179,999	$ 6,300,198	$ 227,116	$ 9,569,027	$ 344,954	$ 69,712,555	$ 2,513,070	$ 85,581,780	$ 3,085,140	$ (15,393,646)	$ (554,926)	$ 4,190,361	$ 151,058	$ 121,833	$ 4,392	$ (12,246,443)	$ (441,472)	$ (7,488,362)	$ (269,948)	$ 253,626,645	$ 9,142,994	$ 14,544,415	$ 524,312	$ (1,164,991)	$ (41,996)
Ending balance, shares at Dec. 31, 2021 | shares			4,408,650	4,408,650

Consolidated Statements of Cash

Consolidated Statements of Cash Flows $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
CASH FLOWS FROM OPERATING ACTIVITIES
Profit before income tax	$ 80,193,769	$ 2,890,906	$ 35,768,798	$ 23,279,811
Adjustments for:
Depreciation expense	50,470,157	1,819,400	47,525,688	46,890,235
Amortization expense	4,054,120	146,147	3,733,377	3,576,606
Net loss (gain) on fair value change of financial assets and liabilities at fair value through profit or loss	1,490,005	53,713	71,848	(1,646,822)
Finance costs	2,831,307	102,066	3,459,511	4,203,395
Interest income	(542,329)	(19,550)	(520,783)	(549,681)
Dividend income	(289,852)	(10,449)	(150,715)	(185,061)
Share-based payments compensation	699,211	25,206	955,575	871,699
Share of profit of associates and joint ventures	(899,700)	(32,433)	(547,612)	(182,275)
Loss (gain) on disposal of property, plant and equipment	(71,770)	(2,587)	(460,868)	164,467
Impairment loss recognized on financial assets	4,718	170		400,201
Reversal of impairment loss recognized on financial assets			(56,950)	(35,727)
Impairment loss recognized on non- financial assets	774,712	27,929	2,486,066	653,140
Gain on disposal of subsidiaries	(17,340,418)	(625,105)	(802,753)
Gain on remeasurement of investments accounted for using the equity method				(319,712)
Loss (gain) on disposal of investments accounted for using the equity method	67,482	2,433	(91,297)
Gain from bargain purchase - acquisition of subsidiaries	(33,114)	(1,193)
Net gain on foreign currency exchange	(1,668,522)	(60,149)	(2,543,821)	(1,498,107)
Others	(74,356)	(2,680)	(295,859)	8,687
Changes in operating assets and liabilities
Financial assets mandatorily at fair value through profit or loss	2,174,012	78,371	2,188,285	6,102,421
Contract assets	(1,345,069)	(48,489)	1,113,950	(1,408,816)
Trade receivables	(27,957,812)	(1,007,852)	(9,396,304)	995,839
Other receivables	(354,849)	(12,792)	(773,411)	(10,755)
Inventories	(23,325,588)	(840,865)	(13,559,192)	1,407,099
Other current assets	(819,252)	(29,533)	366,237	(1,206,456)
Other operating activities assets	(785,204)	(28,306)	(14,396)
Financial liabilities held for trading	(3,814,095)	(137,495)	(2,763,864)	(1,053,535)
Trade payables	13,654,819	492,243	14,032,779	(1,024,250)
Other payables	5,938,081	214,062	3,601,102	1,515,776
Other current liabilities	5,552,277	200,154	23,520	655,694
Other operating activities liabilities	2,017,904	72,743	(301,838)	267,965
Cash generated from operations	90,600,644	3,266,065	83,047,073	81,871,838
Interest received	527,551	19,018	479,900	549,846
Dividend received	655,537	23,631	512,287	518,115
Interest paid	(2,625,883)	(94,661)	(3,442,545)	(4,015,673)
Income tax paid	(7,423,947)	(267,626)	(5,536,077)	(6,620,876)
Net cash generated from operating activities	81,733,902	2,946,427	75,060,638	72,303,250
CASH FLOWS FROM INVESTING ACTIVITIES
Purchase of financial assets at fair value through other comprehensive income	(32,246)	(1,162)	(259,168)	(409,985)
Proceeds from sale of financial assets at fair value through other comprehensive income	672	24	20,686
Return of capital from financial assets at fair value through other comprehensive income	14,201	512	84,186	12,664
Purchase of financial assets at fair value through profit or loss				(26,852)
Proceeds from sale of financial assets at amortized cost	26,531	956
Acquisition of associates and joint ventures	(226,560)	(8,167)	(186,071)	(2,107,844)
Proceeds from disposal of investments accounted for using the equity method			2,271,618
Net cash outflow on acquisition of subsidiaries	(180,718)	(6,515)	(8,745,638)	(81,646)
Proceeds from disposal of subsidiaries	23,941,276	863,060	3,717,039
Return of capital from investments accounted for using the equity method			125,005
Payments for property, plant and equipment	(70,905,659)	(2,556,080)	(62,077,446)	(56,810,153)
Proceeds from disposal of property, plant and equipment	1,605,002	57,859	4,449,113	448,939
Payments for intangible assets	(1,069,866)	(38,568)	(982,655)	(1,411,068)
Proceeds from disposal of intangible assets	1,421	51	8,353	6,929
Payments for right-of-use assets	(956,218)	(34,471)	(118,354)	(288,052)
Payments for investment properties			(6,352)	(2,532)
Proceeds from disposal of investment properties				5
Increase in other financial assets	(372,091)	(13,414)	(822,959)	(2,275,354)
Decrease in other financial assets	447,665	16,138	1,083,934	8,561,929
Increase in other non-current assets	(1,416,675)	(51,070)	(1,338,269)	(216,158)
Decrease in other non-current assets	324,270	11,690	1,244,650	20,032
Income tax paid	(570,700)	(20,573)
Proceeds from disposal of right-of-use assets	278,126	10,026	585,902
Other investing activities items			123	89
Net cash used in investing activities	(49,091,569)	(1,769,704)	(60,946,303)	(54,579,057)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from short-term borrowings	10,043,398	362,055
Repayment of short-term borrowings			(1,502,323)	(4,683,142)
Proceeds from bonds offering	3,280,943	118,275	19,967,149	19,279,033
Repayment of bonds payable	(7,000,000)	(252,343)	(250,000)
Proceeds from long-term borrowings	190,192,666	6,856,260	180,020,420	165,757,252
Repayment of long-term borrowings	(174,173,841)	(6,278,797)	(206,520,559)	(164,612,521)
Repayment of the principle portion of lease liabilities	(907,403)	(32,711)	(844,357)	(636,556)
Dividends paid	(18,082,500)	(651,857)	(8,520,982)	(10,623,030)
Proceeds from exercise of employee share options	2,727,915	98,339	1,934,530	1,149,227
Payments for buy-back of ordinary shares	(5,529,255)	(199,324)
Decrease in non-controlling interests	(6,400,212)	(230,721)	(6,291,089)	(12,117,251)
Other financing activities items	(22,557)	(813)	11,867	(11,820)
Net cash used in financing activities	(5,870,846)	(211,637)	(21,995,344)	(6,498,808)
EFFECTS OF EXCHANGE RATE CHANGES ON THE BALANCE OF CASH AND CASH EQUIVALENTS HELD IN FOREIGN CURRENCY	(2,236,213)	(80,613)	(711,795)	(2,612,946)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	24,535,274	884,473	(8,592,804)	8,612,439
CASH AND CASH EQUIVALENTS AT THE BEGINNING OF THE YEAR	51,538,071	1,857,897	60,130,875	51,518,436
CASH AND CASH EQUIVALENTS AT THE END OF THE YEAR	$ 76,073,345	$ 2,742,370	$ 51,538,071	$ 60,130,875

General Information

General Information	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
General Information	1. GENERAL INFORMATION ASE Technology Holding Co., Ltd. (the “Company”) is a corporation incorporated in Nanzih Technology Industrial Park under the laws of Republic of China (“R.O.C.”) starting from April 30, 2018 (date of incorporation). The Company and its subsidiaries (collectively referred to as the “Group”) offer a comprehensive range of semiconductors packaging, testing, and electronic manufacturing services (“EMS”). The Company’s subsidiaries, Advanced Semiconductor Engineering, Inc. (symbol “2311”, “ASE”) and Siliconware Precision Industries Co., Ltd. (symbol “2325”, “SPIL”), entered into and executed a joint share exchange agreement to establish the Company and the Company acquired all issued and outstanding ordinary shares of ASE and SPIL on April 30, 2018. Both of ASE’s and SPIL’s ordinary shares have been delisted while the ordinary shares of the Company were listed starting from the same date under the symbol “3711”. In addition, ASE’s ordinary shares that have been traded on the New York Stock Exchange (the “NYSE”) under the symbol “ASX” in the form of American Depositary Shares (“ADS”) starting from September 2000 were exchanged as the Company’s ADSs under the same symbol “ASX” starting from April 30, 2018. The ordinary shares of the Company’s subsidiary, Universal Scientific Industrial (Shanghai) Co., Ltd. (“USISH”), have been listed on the Shanghai Stock Exchange under the symbol “601231” since February 2012. The consolidated financial statements are presented in the Company’s functional currency, New Taiwan dollar (NT$).

Approval of Financial Statement

Approval of Financial Statements	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Approval of Financial Statements	2. APPROVAL OF FINANCIAL STATEMENTS The consolidated financial statements were authorized for issue by the management on March 22, 2022.

Application of New and Revised

Application of New and Revised International Financial Reporting Standards as Issued by the International Accounting Standards Board ("IASB") ( Collectively, "IFRSs")	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Application of New and Revised International Financial Reporting Standards as Issued by the International Accounting Standards Board ("IASB") ( Collectively, "IFRSs")	3. APPLICATION OF NEW AND REVISED INTERNATIONAL FINANCIAL REPORTING STANDARDS AS ISSUED BY THE INTERNATIONAL ACCOUNTING STANDARDS BOARD (“IASB”) (collectively, “IFRSs”) a. Amendments to IFRSs that are mandatorily effective for the current year In the current year, the Group applied the amendments to IFRS 9, IAS 39, IFRS 7, IFRS 4 and IFRS 16 “Interest Rate Benchmark Reform—Phase 2” and amendment to IFRS 16 “Covid-19-Related Except for the following, the initial application of the aforementioned new, revised or amended standards and interpretations did not have material impact on the Group’s accounting policies: Amendment to IFRS 16 “Covid-19-Related The Group elected to apply the amendment that extends the availability of the practical expedient to lease payments due on or before June 30, 2022. Refer to Note 4 for the relevant accounting policies of the practical expedient. The Group applies the amendment from January 1, 2021. b. New, revised or amended standards and interpretations in issue but not yet effective The Group has not applied the following new, revised or amended standards and interpretations that have been issued but are not yet effective: New, Revised or Amended Standards and Interpretations Effective Date Announced by IASB (Note 1) “Annual Improvements to IFRS Standards 2018–2020” January 1, 2022 (Note 2) Amendments to IFRS 3 “Reference to the Conceptual Framework” January 1, 2022 (Note 3) Amendments to IAS 16 “Property, Plant and Equipment—Proceeds before Intended Use” January 1, 2022 (Note 4) Amendments to IAS 37 “Onerous Contracts–Cost of Fulfilling a Contract” January 1, 2022 (Note 5) Amendments to IFRS 10 and IAS 28 “Sale or Contribution of Assets between an Investor and its Associate or Joint Venture” To be determined by IASB Amendments to IAS 1 “Classification of Liabilities as Current or Non-current” January 1, 2023 Amendments to IAS 1 “Disclosure of Accounting Policies” January 1, 2023 (Note 6) Amendments to IAS 8 “Definition of Accounting Estimates” January 1, 2023 (Note 7) Amendments to IAS 12 “Deferred Tax related to Assets and Liabilities arising from a Single Transaction” January 1, 2023 (Note 8) Note 1: Unless stated otherwise, the above New IFRSs are effective for annual reporting periods beginning on or after their respective effective dates. Note 2: The amendments to IFRS 9 will be applied prospectively to modifications and exchanges of financial liabilities that occur on or after the annual reporting periods beginning on or after January 1, 2022. Note 3: The amendments are applicable to business combinations for which the acquisition date is on or after the beginning of the annual reporting period beginning on or after January 1, 2022. Note 4: The amendments are applicable to property, plant and equipment that are brought to the location and condition necessary for them to be capable of operating in the manner intended by management on or after January 1, 2021. Note 5: The amendments are applicable to contracts for which the entity has not yet fulfilled all its obligations on January 1, 2022. Note 6: The amendments will be applied prospectively for annual reporting periods beginning on or after January 1, 2023. Note 7: The amendments are applicable to changes in accounting estimates and changes in accounting policies that occur on or after the beginning of the annual reporting period beginning on or after January 1, 2023. Note 8: Except for deferred taxes that will be recognized on January 1, 2022 for temporary differences associated with leases and decommissioning obligations, the amendments will be applied prospectively to transactions that occur on or after January 1, 2022. c. Significant changes in accounting policy resulted from new, revised and amended standards and interpretations in issue but not yet effective Except for the following, as of the date that the accompanying consolidated financial statements were authorized for issue, the Group does not expect that the application of the aforementioned new, revised or amended standards and interpretations will have a material impact on the financial statements. 1) Amendments to IAS 16 “Property, Plant and Equipment: Proceeds before Intended Use” The amendments prohibit an entity from deducting from the cost of an item of property, plant and equipment any proceeds from selling items produced while bringing that asset to the location and condition necessary for it to be capable of operating in the manner intended by management. The cost of those items is measured in accordance with IAS 2 “Inventories”. Any proceeds from selling those items and the cost of those items are recognized in profit or loss in accordance with applicable standards. The amendments are applicable only to items of property, plant and equipment that are brought to the location and condition necessary for them to be capable of operating in the manner intended by management on or after January 1, 2021. 2) Amendments to IAS 37 “Onerous Contracts—Cost of Fulfilling a Contract” The amendments specify that when assessing whether a contract is onerous, the “cost of fulfilling a contract” includes both the incremental costs of fulfilling that contract (for example, direct labor and materials) and an allocation of other costs that relate directly to fulfilling contracts (for example, an allocation of depreciation for an item of property, plant and equipment used in fulfilling the contract). 3 Amendments to IAS 1 “Classification of Liabilities as Current or Non-current” The amendments clarify that for a liability to be classified as non-current, non-current The amendments stipulate that, for the purpose of liability classification, the aforementioned settlement refers to a transfer of cash, other economic resources or the Group’s own equity instruments to the counterparty that results in the extinguishment of the liability. However, if the terms of a liability that could, at the option of the counterparty, result in its settlement by a transfer of the Group’s own equity instruments, and if such option is recognized separately as equity in accordance with IAS 32 “Financial Instruments: Presentation”, the aforementioned terms would not affect the classification of the liability. 4 Amendments to IAS 1 “Disclosure of Accounting Policies” The amendments specify that the Group should refer to the definition of material to determine its material accounting policy information to be disclosed. Accounting policy information is material if it can reasonably be expected to influence decisions that the primary users of general purpose financial statements make on the basis of those financial statements. The amendments also clarify that: • accounting policy information that relates to immaterial transactions, other events or conditions is immaterial and need not be disclosed; • the Group may consider the accounting policy information as material because of the nature of the related transactions, other events or conditions, even if the amounts are immaterial; and • not all accounting policy information relating to material transactions, other events or conditions is itself material. The amendments also illustrate that accounting policy information is likely to be considered as material to the financial statements if that information relates to material transactions, other events or conditions and: (1) the Group changed its accounting policy during the reporting period and this change resulted in a material change to the information in the financial statements; (2) the Group chose the accounting policy from options permitted by the standards; (3) the accounting policy was developed in accordance with IAS 8 “Accounting Policies, Changes in Accounting Estimates and Errors” in the absence of an IFRS that specifically applies; (4) the accounting policy relates to an area for which the Group is required to make significant judgments or assumptions in applying an accounting policy, and the Group discloses those judgments or assumptions; or (5) the accounting is complex and users of the financial statements would otherwise not understand those material transactions, other events or conditions. 5 Amendments to IAS 8 “Definition of Accounting Estimates” The amendments define that accounting estimates are monetary amounts in financial statements that are subject to measurement uncertainty. In applying accounting policies, the Group may be required to measure items at monetary amounts that cannot be observed directly and must instead be estimated. In such a case, the Group uses measurement techniques and inputs to develop accounting estimates to achieve the objective. The effects on an accounting estimate of a change in a measurement technique or a change in an input are changes in accounting estimates unless they result from the correction of prior period errors. 6 Amendments to IAS 12 “Deferred Tax related to Assets and Liabilities arising from a Single Transaction” The amendments clarify that the initial recognition exemption under IAS 12 does not apply to transactions in which equal taxable and deductible temporary differences arise on initial recognition. The Group will recognize a deferred tax asset (to the extent that it is probable that taxable profit will be available against which the deductible temporary difference can be utilized) and a deferred tax liability for all deductible and taxable temporary differences associated with leases and decommissioning obligations on January 1, 2022, and recognize the cumulative effect of initial application in retained earnings at that date. The Group will apply the amendments prospectively to transactions other than leases and decommissioning obligations that occur on or after January 1, 2022.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Significant Accounting Policies	4. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES a. Statement of compliance The consolidated financial statements have been prepared in accordance with IFRSs as issued by the IASB. b. Basis of preparation The consolidated financial statements have been prepared on the historical cost basis except for financial instruments measured at fair value and net defined benefit liabilities which are measured at the present value of the defined benefit obligation less the fair value of plan assets. The fair value measurements, which are grouped into Levels 1 to 3 based on the degree to which the fair value measurement inputs are observable and based on the significance of the inputs to the fair value measurement in its entirety, are described as follows: 1) Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities; 2) Level 2 inputs are inputs other than quoted prices included within Level 1 that are observable for an asset or a liability, either directly (i.e. as prices) or indirectly (i.e. derived from prices); and 3) Level 3 inputs are unobservable inputs for an asset or a liability. c. Classification of current and non-current Current assets include cash and cash equivalents and those assets held primarily for trading purposes or expected to be realized within twelve months after the balance sheet date, unless the asset is to be used for an exchange or to settle a liability, or otherwise remains restricted, at more than twelve months after the balance sheet date. Current liabilities are obligations incurred for trading purposes or to be settled within twelve months after the balance sheet date (even if an agreement to refinance, or to reschedule payments, on a long-term basis is completed after the balance sheet date and before the consolidated financial statements are authorized for issue) and liabilities that do not have an unconditional right to defer settlement for at least 12 months after the balance sheet date (terms of a liability that could, at the option of the counterparty, result in its settlement by the issue of equity instruments do not affect its classification). Assets and liabilities that are not classified as current are classified as non-current. The Group engages in the construction business which has an operating cycle of over one year. The normal operating cycle applies when considering the classification of the Group’s construction-related assets and liabilities. d. Basis of consolidation 1) Principles for preparing consolidated financial statements The consolidated financial statements incorporate the financial statements of the Company and the entities controlled by the Company (i.e. its subsidiaries). Income and expenses of subsidiaries acquired or disposed of during the period are included in the consolidated statement of profit or loss and other comprehensive income from the effective dates of acquisitions up to the effective dates of disposals, as appropriate. When necessary, adjustments are made to the financial statements of subsidiaries to bring their accounting policies into line with those used by the Company. All intra-group transactions, balances, income and expenses are eliminated in full upon consolidation. Total comprehensive income of subsidiaries is attributed to the owners of the Company and to the non-controlling non-controlling Changes in the Group’s ownership interests in subsidiaries that do not result in the Group losing control over the subsidiaries are accounted for as equity transactions. The carrying amounts of the interests of the Group and the non-controlling non-controlling When the Group loses control of a subsidiary, a gain or loss is recognized in profit or loss and is calculated as the difference between (i) the aggregate of the fair value of the consideration received and any investment retained in the former subsidiary at its fair value at the date when control is lost and (ii) the assets (including any goodwill) and liabilities and any non-controlling 2) Subsidiaries included in consolidated financial statements were as follows: Establishment and Operating Percentage of Ownership (%) December 31 Name of Investor Name of Investee Main Businesses Location 2020 2021 The Company ASE Engaged in the packaging and testing of semiconductors R.O.C. 100.0 100.0 USI Inc. (“USIINC”) Holding company R.O.C. 100.0 100.0 SPIL Engaged in the assembly, testing and turnkey services of integrated circuit R.O.C. 100.0 100.0 ASE A.S.E. Holding Limited Holding company Bermuda 100.0 100.0 J & R Holding Limited (“J&R Holding”) Holding company Bermuda 100.0 100.0 Innosource Limited Holding company British Virgin Islands 100.0 100.0 Omniquest Industrial Limited Holding company British Virgin Islands 71.0 71.0 ASE Marketing & Service Japan Co., Ltd. Engaged in marketing and sales services Japan 100.0 100.0 ASE Test, Inc. Engaged in the testing of semiconductors R.O.C. 100.0 100.0 Luchu Development Corporation Engaged in the development of real estate properties R.O.C. 67.1 67.1 Advanced Microelectronic Products Inc. (“AMPI”) Engaged in the manufacturing of integrated circuit R.O.C. 7.6 7.6 ASE Test, Inc. Alto Enterprises Limited Holding company British Virgin Islands 100.0 100.0 Super Zone Holdings Limited Holding company Hong Kong 100.0 100.0 Luchu Development Corporation Engaged in the development of real estate properties R.O.C. 19.0 19.0 TLJ Intertech Inc. Engaged in information software services R.O.C. 60.0 60.0 MingFeng Information Service Corp., Ltd. In the process of liquidation (Liquidation completed in February 2022) R.O.C. 100.0 100.0 AMPI Engaged in the manufacturing of integrated circuit R.O.C. 43.4 43.4 A.S.E. Holding Limited ASE Investment (Labuan) Inc. Holding company Malaysia 70.1 70.1 ASE Test Limited (“ASE Test”) Holding company Singapore 10.2 10.2 ASE Technology Partners, Limited Holding company and was established in August 2021 British Cayman Islands — 100.0 Integrated Solutions Enterprise Europe Trading company, and was acquired in October 2021 (Note 29) Belgium — 100.0 J&R Holding ASE Test Holding company Singapore 89.8 89.8 Omniquest Industrial Limited Holding company British Virgin Islands 8.4 8.4 J&R Industrial Inc. Engaged in leasing equipment and investing activity R.O.C. 100.0 100.0 ASE Japan Co., Ltd. Engaged in the packaging and testing of semiconductors Japan 100.0 100.0 ASE (U.S.) Inc. After-sales service and sales support U.S.A. 100.0 100.0 Global Advanced Packaging Technology Limited Holding company British Cayman Islands 100.0 100.0 Anstock Limited Liquidated in June 2021 British Cayman Islands 100.0 — Anstock II Limited Liquidated in June 2021 British Cayman Islands 100.0 — Suzhou ASEN Semiconductors Co., Ltd. (“ASEN”) Engaged in the packaging and testing of semiconductors (organizational adjustment through exchanged shares to Global Advanced Packaging Test (Hong Kong) Limited in September 2021) Suzhou, China 100.0 — Innosource Limited Omniquest Industrial Limited Holding company British Virgin Islands 20.6 20.6 ASE (Shanghai) Inc. Engaged in the production of substrates Shanghai, China 8.5 8.5 Omniquest Industrial Limited ASE Corporation Holding company British Cayman Islands 100.0 100.0 Alto Enterprises Limited ASE (Kunshan) Inc. Engaged in the packaging and testing of semiconductors Kun Shan, China 22.9 (Note 2 ) ASE Investment (Kun Shan) Limited Holding company Kun Shan, China 85.9 85.9 Super Zone Holdings Limited Advanced Semiconductor Engineering (China) Ltd. Engaged in the packaging and testing of semiconductors, after-sale services, advisory and lease of factory Shanghai, China 100.0 100.0 ASE Investment (Labuan) Inc. ASE (Korea) Inc. (“ASE Korea”) Engaged in the packaging and testing of semiconductors Korea 100.0 100.0 ASE Technology Partners, Limited ASE Technology Acquisition Corporation Holding company and was established in August 2021 British Cayman Islands — 100.0 ASE Korea ASE (Weihai) Inc. Engaged in the packaging and testing of semiconductors (disposed to J&R Holding and organizational adjustment through exchanged shares from J&R Holding to GAPT (Hong Kong) Limited in October 2021) Shandong, China 100.0 — ASE Test ASE Test Holdings, Ltd. Holding company British Cayman Islands 100.0 100.0 ASE Holdings (Singapore) Pte Ltd Holding company Singapore 100.0 100.0 ASE Investment (Labuan) Inc. Holding company Malaysia 29.9 29.9 ASE Singapore Pte. Ltd. Engaged in the packaging and testing of semiconductors Singapore 100.0 100.0 ASE Test Holdings, Ltd. ISE Labs, Inc. Engaged in the testing of semiconductors U.S.A. 100.0 100.0 Establishment and Operating Percentage of Ownership (%) December 31 Name of Investor Name of Investee Main Businesses Location 2020 2021 ISE Labs, Inc. ISE Services, Inc. Engaged in wafer procurement and customer product management services U.S.A. 100.0 100.0 ASE Holdings (Singapore) Pte Ltd ASE Electronics (M) Sdn. Bhd. Engaged in the packaging and testing of semiconductors Malaysia 100.0 100.0 Global Advanced Packaging Technology Limited ASE Assembly & Test (Shanghai) Limited Engaged in the packaging and testing of semiconductors and leasing of properties Shanghai, China 100.0 100.0 ASE Advanced Semiconductor (Shanghai) Limited Engaged in the packaging and testing of semiconductors (disposed to ASEN in November 2021) Shanghai, China 100.0 — GAPT Holding Limited Holding company and was established in August 2021 British Virgin Islands — (Note 2 ) GAPT Holding Limited Global Advanced Packaging Test (Hongkong) Limited Engaged in the trading of substrates and was established in August 2021 Hong Kong — (Note 2 ) Global Advanced Packaging Test (Hongkong) Limited Suzhou ASEN Semiconductors Co., Ltd. (“ASEN”) Engaged in the packaging and testing of semiconductors (acquired from J&R Holding in September 2021 ) Suzhou, China — (Note 2 ) ASE (Weihai) Inc. Engaged in the packaging and testing of semiconductors (acquired from J&R Holding in October 2021 through share exchange under restructure ) Shandong, China — (Note 2 ) ASEN ASE Advanced Semiconductor (Shanghai) Limited Engaged in the packaging and testing of semiconductors (acquired from Global Advanced Packaging Technology Limited in November 2021) Shanghai, China — (Note 2 ) ASE Assembly & Test (Shanghai) Limited ASE Investment (Kun Shan) Limited Holding company Kun Shan, China 14.1 14.1 Wuxi Tongzhi Microelectronics Co., Ltd. Engaged in the packaging and testing of semiconductors Wuxi, China 100.0 100.0 ISE Labs, China, Ltd. Engaged in the testing of semiconductor Shanghai, China 100.0 100.0 Shanghai Ding Hui Real Estate Development Co., Ltd. (“DH”) Engaged in the development, construction and sale of real estate properties Shanghai, China 60.0 60.0 DH Shanghai Ding Qi Property Management Co., Ltd. Engaged in the management of real estate properties Shanghai, China 100.0 100.0 Shanghai Ding Wei Real Estate Development Co., Ltd. (“DW”) Engaged in the development, construction and leasing of real estate properties Shanghai, China 100.0 100.0 Shanghai Ding Yu Real Estate Development Co., Ltd. Engaged in the development, construction and leasing of real estate properties Shanghai, China 100.0 100.0 Kun Shan Ding Hong Real Estate Development Co., Ltd Engaged in the development, construction and leasing of real estate properties Kun Shan, China 100.0 100.0 Shanghai Ding Xu Property Management Co., Ltd. Engaged in the management of real estate properties Shanghai, China 100.0 100.0 Shanghai Dingyao Estate Development Co., Ltd. Engaged in the management of real estate properties Shanghai, China 100.0 100.0 Shanghai Ding Fan Business Management Co., Ltd. Engaged in the management of real estate properties (acquired from DW in November 2020) Shanghai, China 100.0 100.0 ASE Investment (Kun Shan) Limited ASE (Kun s Engaged in the packaging and testing of semiconductors Kun Shan, China 49.3 (Note 2 ) ASE Corporation ASE Mauritius Inc. Holding company Mauritius 100.0 100.0 ASE Labuan Inc. Holding company Malaysia 100.0 100.0 ASE Mauritius Inc. ASE (Kunshan) Inc. Engaged in the packaging and testing of semiconductors Kun Shan, China 27.8 (Note 2 ) ASE (Shanghai) Inc. Engaged in the production of substrates Shanghai, China 91.5 91.5 ASE Labuan Inc. ASE Electronics Inc. Engaged in the production of substrates R.O.C. 100.0 100.0 ASE (Shanghai) Inc. Advanced Semiconductor Engineering (HK) Limited Engaged in the trading of substrates Hong Kong 100.0 100.0 Shanghai Ding Hui Real Estate Development Co., Ltd. Engaged in the development, construction and sale of real estate properties Shanghai, China 40.0 40.0 Universal Scientific Industrial (Shanghai) Co., Ltd. (“USISH”) Engaged in the designing, manufacturing and sales of electronic components Shanghai, China 0.8 0.8 USIINC Huntington Holdings International Co., Ltd. Holding company British Virgin Islands 100.0 100.0 Huntington Holdings International Co., Ltd. Unitech Holdings International Co., Ltd. Holding company British Virgin Islands 100.0 100.0 Real Tech Holdings Limited Holding company British Virgin Islands 100.0 100.0 Universal ABIT Holding Co., Ltd. In the process of liquidation British Cayman Islands 100.0 100.0 Real Tech Holdings Limited USI Enterprise Limited (“USIE”) Engaged in the service of investment advisory and warehousing management Hong Kong 95.9 100.0 USIE USISH Engaged in the designing, manufacturing and sales of electronic components Shanghai, China 76.6 77.1 USISH Universal Global Technology Co., Limited Holding company Hong Kong 100.0 100.0 Establishment and Operating Percentage of Ownership (%) December 31 Name of Investor Name of Investee Main Businesses Location 2020 2021 Universal Global Technology (Kunshan) Co., Ltd. (“UGKS”) Engaged in the designing and manufacturing of electronic components Kun Shan, China 100.0 100.0 Universal Global Technology (Shanghai) Co., Ltd. Engaged in the processing and sales of computer and communication peripherals as well as business in import and export of goods and technology Shanghai, China 100.0 100.0 Universal Global Electronics (Shanghai) Co., Ltd. Engaged in the sales of electronic components and telecommunications equipment Shanghai, China 100.0 100.0 USI Electronics (Shenzhen) Co., Ltd. Engaged in the design, manufacturing and sales of motherboards and computer peripherals Shenzhen, China 50.0 50.0 Universal Global Technology (Huizhou) Co., Ltd. Engaged in the research and manufacturing of new electronic applications, communications, computers and other electronics products and also provided auxiliary technical services as well as import and export services Huizhou, China 100.0 100.0 FINANCIERE AFG (“FAFG”) Holding company France 10.4 10.4 Universal Global Technology Co., Limited Universal Global Industrial Co., Limited Engaged in manufacturing, trading and investing activity Hong Kong 100.0 100.0 Universal Global Scientific Industrial Co., Ltd. (“UGTW”) Engaged in the manufacturing of components of telecommunication and cars and provision of related R&D services R.O.C. 100.0 100.0 USI America Inc. Engaged in the manufacturing and processing of motherboards and wireless network communication and provision of related technical service U.S.A. 100.0 100.0 Universal Scientific Industrial De Mexico S.A. De C.V. Engaged in the assembling of motherboards and computer components Mexico 100.0 100.0 USI Japan Co., Ltd. Engaged in the manufacturing and sales of computer peripherals, integrated chip and other related accessories Japan 100.0 100.0 USI Electronics (Shenzhen) Co., Ltd. Engaged in the design, manufacturing and sales of motherboards and computer peripherals Shenzhen, China 50.0 50.0 Universal Global Electronics Co., Ltd. Engaged in accepting and outsourcing orders as well as sales of electronic components and service of technical advisory Hong Kong 100.0 100.0 Universal Scientific Industrial (France) (“USIFR”) Engaged in investing activities France 100.0 100.0 UNIVERSAL INDUSTRIA L TNAM CO ., Engaged in IC assembly for wearable devices and was established in July 2020. Vietnam 100.0 100.0 Universal Global Industrial Co., Limited Universal Scientific Industrial De Mexico S.A. De C.V. Engaged in the assembling of motherboards and computer components Mexico (Note 1 ) (Note 1 ) UGTW Universal Scientific Industrial Co., Ltd. (“USI”) Engaged in the manufacturing, processing and sales of computers, computer peripherals and related accessories R.O.C. 100.0 100.0 Universal Global Electronics Co., Ltd. Universal Scientific Industrial Poland Sp. z o.o. (“USIPL”) Engaged in the design and manufacturing of electronic components and new electronic applications. Poland 100.0 100.0 Universal Global Electronics (Shanghai) Co., Ltd. USI Science and Technology (Shenzhen) Co., Ltd. Engaged in the design of electronic components, service of technical advisory; wholesale of electronic components and communication peripherals as well as business in import and export of goods and management of properties. Established in November 2020. Shenzhen, China 100.0 100.0 USIFR FAFG Holding company France 89.6 89.6 ASTEELFLASH GROUP Holding company (disposed to FAFG in October 2021) France (Note 1 ) — Establishment and Operating Percentage of Ownership (%) December 31 Name of Investor Name of Investee Main Businesses Location 2020 2021 FAFG ASTEELFLASH GROUP Holding company (acquired 1 share from Universal Scientific Industrial (France) in October 2021) France 100.0 100.0 MANUFACTURING POWER TUNISIA Engaged in the design and manufacturing of electronic components Tunisia 0.1 0.1 ASTEELFLASH MEXICO S.A. de C.V. Engaged in the design and manufacturing of electronic components Mexico 0.1 0.1 ASTEELFLASH GROUP ASTEELFLASH (BEDFORD) LIMITED Engaged in the design and manufacturing of electronic components United Kingdom 100.0 100.0 ASTEELFLASH FRANCE Engaged in the design and manufacturing of electronic components France 99.9 99.9 ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia 100.0 100.0 ASTEELFLASH HONG KONG LIMITED Holding company Hong Kong 100.0 100.0 ASTEELFLASH MEXICO S.A. de C.V. Engaged in the design and manufacturing of electronic components Mexico 99.9 99.9 ASTEELFLASH GERMANY GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 MANUFACTURING POWER TUNISIA Engaged in the design and manufacturing of electronic components Tunisia 99.9 99.9 ASTEELFLASH US HOLDING CORP. Holding company U.S.A. 100.0 100.0 ASTEEL ELECTRONIQUE FOUCHANA Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH TUNISIE S.A. in June 2021) Tunisia (Note 1 ) — AFERH TUNISIE Engaged in the management, training and consulting of human resources Tunisia 0.5 0.5 ASTEEL ELECTRONICS MANUFACTURING SERVICES Engaged in the design and manufacturing of electronic components Tunisia 0.1 0.1 ASTEELFLASH PLZEN S.R.O. Engaged in the design and manufacturing of electronic components (acquired from ASTEELFLASH GERMANY GmbH in April 2021) Czech Republic — 100.0 ASTEELFLASH (BEDFORD) LIMITED ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1 ) (Note 1 ) ASTEELFLASH TECHNOLOGIE ASTEELFLASH FRANCE Engaged in the design and manufacturing of electronic components France (Note 1 ) (Note 1 ) ASTEELFLASH FRANCE SCI CHASSET Engaged in the management and operation of real estate properties and holding the ownership of real estate properties (Liquidated in July 2021) France 100.0 — AFERH Engaged in the management, training and consulting of human resources (Liquidated in July 2021) France 100.0 — ASTEEL ELECTRONICS MANUFACTURING SERVICES Engaged in the design and manufacturing of electronic components Tunisia 99.9 99.9 ASTEEL ELECTRONIQUE FOUCHANA Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH TUNISIE S.A. in June 2021) Tunisia 94.2 — ASTEELFLASH TECHNOLOGIE Engaged in projection of plastic and the design and manufacturing of industrial components France 100.0 100.0 ASTEELFLASH BRETAGNE Engaged in the design and manufacturing of electronic components France 100.0 100.0 ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1 ) (Note 1 ) ASTEELFLASH TUNISIE S.A. ASTEEL ELECTRONIQUE TUNISIE Engaged in the design and manufacturing of electronic components (merged by ASTEELFLASH TUNISIE S.A.in December 2021) Tunisia 100.0 — ASTEEL ELECTRONIQUE FOUCHANA Engaged in the design and manufacturing of electronic components (acquired from ASTEELFLASH GROUP, ASTEELFLASH FRANCE, Asteelflash Suzhou Co., Ltd. and ASTEELFLASH USA CORP.in June 2021 and merged by ASTEELFLASH TUNISIE S.A. in December 2021) Tunisia (Note 1 ) — AFERH AFERH TUNISIE Engaged in the management, training and consulting of organization and human resources Tunisia 99.5 99.5 ASTEELFLASH HONG KONG LIMITED Asteelflash S ou Co., Ltd . Engaged in the design and manufacturing of electronic components Suzhou, China 100.0 100.0 Asteelflash Suzhou Co., Ltd. A STE EL ELECT R ONIQUE FO UCHANA Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH TUNISIE S.A. in June 2021) Tunisia (Note 1 ) — ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1 ) (Note 1 ) ASTEELFLASH GERMANY GmbH ASTEELFLASH HERSFELD GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 ASTEELFLASH EBERBACH GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 Establishment and Operating Percentage of Ownership (%) December 31 Name of Investor Name of Investee Main Businesses Location 2020 2021 ASTEELFLASH BONN GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 ASTEELFLASH SCHWANDORF GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 ASTEELFLASH PLZEN S.R.O. Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH GROUP in April 2021) Czech Republic 100.0 — ASTEELFLASH DESIGN SOLUTIONS HAMBOURG GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 EN ELECTRONICNETWORK SRL Engaged in the design and manufacturing of electronic components Romania 100.0 100.0 ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1) (Note 1 ) ASTEELFLASH MEXICO S.A. de C.V. ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1) (Note 1 ) ASTEELFLASH US HOLDING CORP. ASTEELFLASH USA CORP. Engaged in the design and manufacturing of electronic components U.S.A. 100.0 100.0 ASTEELFLASH USA CORP. ASTEEL ELECTRONIQUE FOUCHANA Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH TUNISIE S.A. in June 2021) Tunisia (Note 1) — ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1) (Note 1 ) SPIL SPIL (B.V.I.) Holding Limited Engaged in investing activities British Virgin Islands 100.0 100.0 Siliconware Investment Co., Ltd. Engaged in investing activities R.O.C. 100.0 100.0 SPIL (B.V.I.) Holding Limited Siliconware USA, Inc. Engaged in marketing activities U.S.A. 100.0 100.0 SPIL (Cayman) Holding Limited Engaged in investing activities British Cayman Islands 100.0 100.0 SPIL (Cayman) Holding Limited Siliconware Technology (Suzhou) Limited (“SZ”) Engaged in the packaging and testing of semiconductors Suzhou, China 100.0 100.0 Note 1: The number of shares held was 1 share or 3 shares and the percentage of ownership was less than 0.1%. Note 2: In December 2021, the Company’s board of directors resolved to dispose its 100% shareholdings in those subsidiaries, which were settled in December 2021 and resulted in losing its control over those subsidiaries. Refer to Note 30 DISPOSAL OF SUBSIDIARIES for related disclosure. e. Business combinations Acquisitions of businesses are accounted for using the acquisition method. Acquisition-related costs are generally recognized in profit or loss as they are incurred. Goodwill is measured as the excess of the sum of the consideration transferred, the amount of any non-controlling re-assessment, non-controlling Where the consideration the Group transfers in a business combination includes assets or liabilities resulting from a contingent consideration arrangement, the contingent consideration is measured at its acquisition-date fair value and considered as part of the consideration transferred in a business combination. Changes in the fair value of the contingent consideration that qualify as measurement period adjustments are adjusted retrospectively, with the corresponding adjustments being made against goodwill or gains on bargain purchases. Measurement period adjustments are adjustments that arise from additional information obtained during the measurement period about facts and circumstances that existed as of the acquisition date. The measurement period does not exceed 1 year from the acquisition date. The subsequent accounting for changes in the fair value of the contingent consideration that do not qualify as measurement period adjustments depends on how the contingent consideration is classified. Contingent consideration not classified as equity is remeasured at fair value at the end of subsequent reporting period with any gain or loss recognized in profit or loss. When a business combination is achieved in stages, the Group’s previously held equity interest in an acquiree is remeasured to fair value at acquisition date, and the resulting gain or loss, if any, is recognized in profit or loss or other comprehensive income. Amounts arising from interests in the acquiree prior to the acquisition date that have previously been recognized in other comprehensive income are recognized on the same basis as would be required had those interest been directly disposed of by the Group. If the initial accounting for a business combination is incomplete by the end of the reporting period in which the combination occurs, the Group reports provisional amounts for the items for which the accounting is incomplete. Those provisional amounts are adjusted retrospectively during the measurement period, or additional assets or liabilities are recognized, to reflect new information obtained about facts and circumstances that existed at the acquisition date that, if known, would have affected the amounts recognized at that date. Business combination involving entities under common control is not accounted for using the acquisition method but is accounted for at the carrying amounts of the entities. The Group elected not to restate comparative information of the prior period in the financial statements as the business combination was an organization restructure under common control. f. Foreign currencies In preparing the financial statements of each individual entity, transactions in currencies other than the entity’s functional currency (i.e. foreign currencies) are recognized at the rates of exchange prevailing at the dates of the transactions. At each balance sheet date, monetary items denominated in foreign currencies are retranslated at the rates prevailing at that date. Exchange differences on monetary items arising from settlement or translation are recognized in profit or loss in the period in which they arise except for exchange differences on transactions entered into in order to hedge certain foreign currency risks. Non-monetary non-monetary non-monetary Non-monetary For the purposes of presenting the consolidated financial statements, the assets and liabilities of the Group’s foreign operations (including subsidiaries, associates and joint ventures in other countries that use currencies which are different from the currency of the Company) are translated into the New Taiwan dollars using exchange rates prevailing at each balance sheet date. Income and expense items are translated at the average exchange rates for the period. The resulting currency translation differences are recognized in other comprehensive income and accumulated in equity attributed to the owners of the Company and non-controlling On the disposal of the Group’s entire interest in a foreign operation, or a disposal involving the loss of control over a subsidiary that includes a foreign operation, or a partial disposal of an interest in a joint arrangement or an associate that includes a foreign operation of which the retained interest becomes a financial asset, all of the exchange differences accumulated in equity in respect of that operation attributable to the owners of the Company are reclassified to profit or loss. In relation to a partial disposal of a subsidiary that does not result in the Group losing control over the subsidiary, the proportionate share of accumulated exchange differences is re-attributed non-controlling Goodwill and fair value adjustments recognized on identifiable assets and liabilities of acquired foreign operation are treated as assets and liabilities of the foreign operation and translated at the rates of exchange prevailing at the end of each reporting period. Exchange differences are recognized in other comprehensive income. g. Inventories and inventories related to real estate business Inventories, including raw materials, supplies, work in process, finished goods, and materials and supplies in transit are stated at the lower of cost or net realizable value. Inventory write-downs are made by item, except for those that may be appropriate to group items of similar or related inventories. Net realizable value is the estimated selling prices of inventories less all estimated costs of completion and estimated costs necessary to make the sale. Raw materials and supplies are recorded at moving average cost while work in process and finished goods are recorded at standard cost. Inventories related to real estate business include land and buildings held for sale, land held for construction and construction in progress. Land held for development is recorded as land held for construction upon obtaining the title of ownership. Prior to the completion, the borrowing costs directly attributable to construction in progress are capitalized as part of the cost of the asset. Construction in progress is transferred to land and buildings held for sale upon completion. Land and buildings held for sale, construction in progress and land held for construction are stated at the lower of cost or net realizable value and related write-downs are made by item. The amounts received in advance for real estate properties are first recorded as advance receipts and then recognized as revenue when the construction is completed and the title and significant risk of the real estate properties are transferred to customers. Cost of sales of land and buildings held for sale are recognized based on the ratio of property sold to the total property developed. h. Investments in associates and joint ventures An associate is an entity over which the Group has significant influence and that is neither a subsidiary nor an interest in a joint venture. Joint venture is a joint arrangement whereby the Group and other parties that have joint control of the arrangement have rights to the net assets of the arrangement. The Group applies the equity method to investments in an associate and joint venture. Under the equity method, investments in an associate and a joint venture are initially recognized at cost and adjusted thereafter to recognize the Group’s share of the profit or loss and other comprehensive income of the associate and joint venture. The Group also recognizes the changes in the Group’s share of equity of associates and joint venture. Any excess of the cost of acquisition over the Group’s share of the net fair value of the identifiable assets and liabilities of an associate or a joint venture at the date of acquisition is recognized as goodwill, which is included within the carrying amount of the investment and is not amortized. Any excess of the Group’s share of the net fair value of the identifiable assets and liabilities over the cost of acquisition after reassessment is recognized immediately in profit or loss. When the Group subscribes for additional new shares of an associate and joint venture at a percentage different from its existing ownership percentage, the resulting carrying amount of the investment differs from the amount of the Group’s proportionate interest in the associate and joint venture. The Group records such a difference as an adjustment to investments with the corresponding amount charged to gain or l

Critical Accounting Judgments a

Critical Accounting Judgments and Key Sources of Estimation Uncertainty	12 Months Ended
	Dec. 31, 2021
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Critical Accounting Judgments and Key Sources of Estimation Uncertainty	5. CRITICAL ACCOUNTING JUDGMENTS AND KEY SOURCES OF ESTIMATION UNCERTAINTY In the application of the Group’s accounting policies, management is required to make judgments, estimates and assumptions on the carrying amounts of assets and liabilities that are not readily apparent from other sources. The estimates and underlying assumptions are based on historical experience and other factors that are considered to be relevant. Actual results may differ from these estimates. The Group considers the recent development of the COVID-19 R.O . C . year year year year s years Impairment of goodwill Determining whether goodwill is impaired requires an estimation of the value in use of the cash-generating units to which goodwill has been allocated. The calculation of the value in use requires management to estimate the future cash flows expected to be generated from the cash-generating units and a suitable discount rate in order to calculate the present value. Where the actual future cash flows are less than expected, or change in facts and circumstances results in downward revision of future cash flows or upward revision of discount rate, a material impairment loss may arise.

Cash and Cash Equivalents

Cash and Cash Equivalents	12 Months Ended
	Dec. 31, 2021
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Cash and Cash Equivalents	6. CASH AND CASH EQUIVALENTS December 31 2020 2021 NT$ NT$ US$ (Note 4) Cash on hand $ 6,073 $ 5,638 $ 203 Checking accounts and demand deposits 48,734,866 47,094,687 1,697,718 Cash equivalents (time deposits with original maturity of less than three months and repurchase agreements collateralized by bonds) 2,797,132 28,973,020 1,044,449 $ 51,538,071 $ 76,073,345 $ 2,742,370

Financial Instruments at Fair V

Financial Instruments at Fair Value Through Profit or Loss	12 Months Ended
	Dec. 31, 2021
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Financial Instruments at Fair Value Through Profit or Loss	7. FINANCIAL INSTRUMENTS AT FAIR VALUE THROUGH PROFIT OR LOSS December 31 2020 (Retrospectively Adjusted) 2021 NT$ NT$ US$ (Note 4) Financial assets mandatorily classified as at FVTPL Derivative instruments (non-designated Swap contracts $ 99,312 $ 85,629 $ 3,087 Forward exchange contracts 122,511 23,373 843 Redemption option and put option of convertible bonds - 8,463 305 Target redemption forward contracts - 500 18 Non-derivative Quoted ordinary shares 4,064,438 2,683,193 96,726 Private-placement funds 1,124,754 1,322,686 47,682 Unquoted preferred shares 385,440 583,270 21,026 Contingent considerations (Note 29) 387,790 394,943 14,237 Open-end 339,338 334,223 12,049 6,523,583 5,436,280 195,973 Current 4,342,605 2,933,446 105,748 Non-current $ 2,180,978 $ 2,502,834 $ 90,225 Financial liabilities held for trading Derivative instruments (non-designated Swap contracts $ 1,448,972 $ 360,797 $ 13,006 Forward exchange contracts 9,020 56,863 2,050 Target redemption forward contracts 79,216 - - Current $ 1,537,208 $ 417,660 $ 15,056 At each balance sheet date, outstanding swap contracts not accounted for hedge accounting were as follows: Notional Amount Currency Maturity Period (In Thousands) December 31, 2020 Sell NT$/Buy US$ 2021.01 2021.12 NT$51,140,082/US$1,755,000 Sell US$/Buy RMB 2021.01 2021.02 US$59,793/RMB395,742 Sell US$/Buy HKD 2021.0 US$13,804/HKD$107,000 Sell US$/Buy JPY 2021.0 US$41,630/JPY4,300,000 Sell US$/Buy KRW 2021.0 US$30,000/KRW33,066,000 Sell US$/Buy NT$ 2021.01 2021.02 US$675,240/NT$19,073,846 December 31, 2021 Sell RMB/Buy US$ 2022.0 RMB2,617,518/US$409,000 Sell NT$/Buy US$ 2022.01 2022.12 NT$52,916,127/US$1,903,000 Sell US$/Buy RMB 2022.0 US$54,415/RMB349,800 Sell US$/Buy JPY 2022.0 US$17,671/JPY2,000,000 Sell US$/Buy KRW 2022.0 US$37,500/KRW44,418,750 Sell US$/Buy NT$ 2022.01 2022.04 US$570,130/ N T $ At each balance sheet date, outstanding forward exchange contracts not accounted for hedge accounting were as follows : Notional Amount Currency Maturity Period (In Thousands) December 31, 2020 Sell RMB/Buy US$ 2021.01 RMB756,946/US$116,093 Sell HKD/Buy US$ 2021.01 HKD4,100/US$529 Sell NT$/Buy US$ 2021.01 2021.02 NT$2,667,230/US$95,000 Sell US$/Buy RMB 2021.01 2021.04 US$363,000/RMB2,385,500 Sell US$/Buy EUR 2021.01 US$1,607/EUR1,320 Sell US$/Buy JPY 2021.01 2021.04 US$100,076/JPY10,405,845 Sell US$/Buy KRW 2021.0 US$16,000/KRW17,575,300 Sell US$/Buy MYR 2021.01 2021.04 US$24,000/MYR98,737 Sell US$/Buy NT$ 2021.01 2021.02 US$27,470/NT$776,867 Sell US$/Buy SGD 2021.01 2021.04 US$18,500/SGD24,868 December 31, 2021 Sell RMB/Buy JPY 2022.01 RMB35,127/JPY630,000 Sell RMB/Buy US$ 2022.01 RMB727,645/US$114,000 Sell NT$/Buy US$ 2022.01 2022.03 NT$3,465,805/US$125,000 Sell US$/Buy RMB 2022.01 2022.06 US$265,000/RMB1,701,695 Sell US$/Buy EUR 2022.01 US$460/EUR407 Sell US$/Buy JPY 2022.01 2022.02 US$94,747/JPY10,789,851 Sell US$/Buy MYR 2022.01 2022.02 US$8,000/MYR33,430 Sell US$/Buy NT$ 2022.01 US$10,000/NT$277,735 Sell US$/Buy SGD 2022.01 2022.02 US$16,900/SGD22,925 As of each balance sheet date, outstanding target redemption forward contracts not accounted for hedge accounting were as follows: Notional Amount Currency Maturity Period (In Thousands) December 31, 2020 Sell EUR/Buy US$ 2022.04 2022.06 EUR23,279/US$27,475 December 31, 2021 Sell EUR/Buy US$ 2022.04 2022.06 EUR2,982/US$3,475 The target redeemable forward contracts held by subsidiaries are weekly settled. If the market exchange rate is lower than the execution rate at the time of settlement, the contract will be settled at the nominal amount, whereas if the market exchange rate is higher than the execution rate, the contract will be settled at a leveraged nominal amount (twice the nominal amount). The contracts last until all the nominal amount of US$ position is fully settled. However, when the accumulated excess of the execution rates over the market exchange rates reach the agreed threshold after the weekly settlement, the contracts will be automatically early terminated.

Financial Assets at Fair Value

Financial Assets at Fair Value Through Other Comprehensive Income (FVTOCI)	12 Months Ended
	Dec. 31, 2021
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Financial Assets at Fair Value Through Other Comprehensive Income (FVTOCI)	8. FINANCIAL ASSETS AT FAIR VALUE THROUGH OTHER COMPREHENSIVE INCOME (FVTOCI) December 31 2020 2021 NT$ NT$ US$ (Note 4) Investments in equity instruments at FVTOCI $ 728,398 $ 943,354 $ 34,007 Investments in debt instruments at FVTOCI 1,012,736 1,076,458 38,805 $ 1,741,134 $ 2,019,812 $ 72,812 a. Investments in equity instruments at FVTOCI December 31 2020 2021 NT$ NT$ US$ (Note 4) Unquoted ordinary shares $ 567,377 $ 820,779 $ 29,588 Quoted ordinary shares — 102,124 3,682 Unquoted preferred shares 151,329 11,245 405 Limited partnership 9,692 9,206 332 $ 728,398 $ 943,354 $ 34,007 b. Investments in debt instruments at FVTOCI December 31 2020 2021 NT$ NT$ US$ (Note 4) Unsecured subordinate corporate bonds $ 1,012,736 $ 1,076,458 $ 38,805 The Group purchased 1,000 units of the abovementioned 3.5

Credit Risk Management for Inve

Credit Risk Management for Investments in Debt Instruments	12 Months Ended
	Dec. 31, 2021
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Credit Risk Management for Investments in Debt Instruments	9. CREDIT RISK MANAGEMENT FOR INVESTMENTS IN DEBT INSTRUMENTS The Group’s investment in unsecured subordinate corporate bonds is rated the equivalent of investment grade or higher and has low credit risk for impairment assessment. There was no significant increase in credit risk of such debt instrument since initial recognition leading to changes in interest rates and terms, and there was also no significant change in bond issuer’s operation affecting the ability performing debt obligation. Therefore, no expected credit losses existed. The Group reviews changes in bond yields and other public information periodically and makes an assessment whether there has been a significant increase in lifetime Expected Credit Loss (“ECL”) since initial recognition.

Trade Receivables, Net

Trade Receivables, Net	12 Months Ended
	Dec. 31, 2021
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Trade Receivables, Net	10. TRADE RECEIVABLES, NET December 31 2020 2021 NT$ NT$ US$ (Note 4) At amortized cost Gross carrying amount $ 91,304,934 $ 109,473,101 $ 3,946,399 Less: Allowance for impairment loss 97,358 103,353 3,726 91,207,576 109,369,478 3,942,673 At FVTOCI 626,413 6,092,462 219,627 $ 91,833,989 $ 115,462,210 $ 4,162,300 a. Trade receivables 1) At amortized cost The Group’s average credit terms granted to the customers were 30 to 90 days. The Group evaluates the risk and probability of credit loss of trade receivables by reference to the Group’s past experiences, financial condition of each customer, impact of COVID-19, The Group measures the loss allowance for trade receivables at an amount equal to lifetime ECLs. The expected credit losses on trade receivables are estimated using a provision matrix by reference to past default experience of the debtor and an analysis of the debtor’s current financial position, adjusted for general economic conditions of the industry in which the debtors operate and an assessment of both the current as well as the forecast direction of economic conditions at each balance sheet date. As the Group’s historical credit loss experience shows significantly different loss patterns for different customer segments, the provision matrix for expected credit loss allowance based on trade receivables due status is further distinguished according to the Group’s different customer base. The Group writes off a trade receivable when there is information indicating that the debtor is in severe financial difficulty and there is no realistic prospect of recovery. For trade receivables that have been written off, the Group continues to engage in enforcement activity to attempt to recover the receivables due. Where recoveries are made, these are recognized in profit or loss. The following table details the loss allowance of trade receivables based on the Group’s provision matrix. December 31, 2020 Not Past Due Overdue 1 to 30 days Overdue 31 to 90 Days Overdue Over 91 Days Individually Total NT$ NT$ NT$ NT$ NT$ NT$ Expected credit loss rate 0% 0%-10% 0%-70% 1%-100% 50%-100% Gross carrying amount $ 86,820,792 $ 3,823,249 $ 557,487 $ 92,873 $ 10,533 $ 91,304,934 Loss allowance (Lifetime ECLs) (18,911 ) (2,053 ) (20,629 ) (45,232 ) (10,533 ) (97,358 ) $ 86,801,881 $ 3,821,196 $ 536,858 $ 47,641 $ — $ 91,207,576 December 31, 2021 Not Past Due Overdue 1 to 30 days Overdue 31 to 90 Days Overdue Over 91 Days Individually Total NT$ NT$ NT$ NT$ NT$ NT$ Expected credit loss rate 0% 0%-10% 0%-70% 1%-100% 0%-100% Gross carrying amount $ 105,538,390 $ 3,136,438 $ 609,695 $ 99,118 $ 89,460 $ 109,473,101 Loss allowance (Lifetime ECLs) (18,062 ) (1,811 ) (22,785 ) (46,337 ) (14,358 ) (103,353 ) $ 105,520,328 $ 3,134,627 $ 586,910 $ 52,781 $ 75,102 $ 109,369,748 The movements of the loss allowance of trade receivables were as f o December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Balance at January 1 $ 155,389 $ 136,497 $ 97,358 $ 3,510 Net remeasurement of loss allowance (38,277 ) (55,742 ) 17,078 616 Reclassification (5,877 ) (6,970 ) — — Acquisition through business combinations 25,553 32,460 — — Amounts written off — (3,944 ) (399 ) (14 ) Disposal of subsidiaries — — (4,637 ) (167 ) Effects of foreign currency exchange differences (291 ) (4,943 ) (6,047 ) (219 ) Balance at December 31 $ 136,497 $ 97,358 $ 103,353 $ 3,726 2) At FVTOCI For the trade receivables due from certain customers, the Group decides whether or not to factor these trade receivables to banks without recourse based on the Group’s demand of working capital. These trade receivables are classified as at FVTOCI because they are held within a business model whose objective is achieved by both the collection The following table details the loss allowance of trade receivables at FVTOCI based on the Group’s provision matrix. December 31, 2020 Not Past Due Overdue 1 to 30 days Overdue 31 to 90 Days Overdue Over 91 Days Individually Total NT$ NT$ NT$ NT$ NT$ NT$ Expected credit loss rate 0% 0% 0% — — Gross carrying amount $ 613,968 $ 9,874 $ 2,571 $ — $ — $ 626,413 Loss allowance (Lifetime ECLs) — — — — — — $ 613,968 $ 9,874 $ 2,571 $ — $ — $ 626,413 December 31, 2021 Not Past Due Overdue 1 to 30 days Overdue 31 to 90 Days Overdue Over 91 Days Individually Total NT$ NT$ NT$ NT$ NT$ NT$ Expected credit loss rate 0% 0% 0% 0% 0% Gross carrying amount $ 5,991,543 $ 9,415 $ 91,493 $ 11 $ — $ 6,092,462 Loss allowance (Lifetime ECLs) — — — — — — $ 5,991,543 $ 9,415 $ 91,493 $ 11 $ — $ 6,092,462 Not Past Due Overdue 1 to 30 days Overdue 31 to 90 Days Overdue Over 91 Days Individually Total US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Expected credit loss rate 0% 0% 0% 0% 0% Gross carrying amount $ 215,989 $ 340 $ 3,298 $ 0 $ — $ 219,627 Loss allowance (Lifetime ECLs) — — — — — — $ 215,989 $ 340 $ 3,298 $ 0 $ — $ 219,627 3) At FVTPL Some of the Group’s subsidiaries sell all of their trade receivables to banks without recourse. The sale will result in the derecognition of these trade receivables because the Group’s subsidiaries will transfer substantially all risks and rewards to banks. These trade receivables are measured at FVTPL because the objective of the subsidiary’ business model is neither held to collect contractual cash flows nor held both to b. Transfers of financial assets The f ollowing s the Counterparty Receivables Reclassified Advances Received- Unused Advances Annual December 31, 2020 BNP Paribas EUR 16,691 EUR 15,315 EUR 14,481 EUR 1,376 0.80 HSBC EUR 6,773 EUR 6,456 EUR 5,779 EUR 317 1.45 Citibank Taiwan Ltd. US$ 94,471 US$ — US$ — US$ 94,471 0.84-0.95 Standard Chartered Bank US$ 53,800 US$ — US$ — US$ 53,800 0.91 First Commercial Bank NT$ 6,879 NT$ — NT$ — NT$ 6,879 1.95 December 31, 2021 BNP Paribas EUR 12,115 EUR 12,081 EUR 11,475 EUR 34 0.80 First Commercial Bank NT$ 8,565 NT$ — NT$ — NT$ 8,565 1.95 Pursuant to the factoring agreements, losses from commercial disputes (such as sales returns and discounts) are borne by the Group, while losses from credit risk are borne by banks. As of December 31, 2020 and 2021, the Group’s issued promissory notes with aggregate amounts of US$2,000 thousand to Citibank Taiwan Ltd. to compensate losses from commercial disputes. As of the date that the consolidated financial statements were authorized for issue by the management, the Group did not have a material commercial dispute and also expected to have no material commercial dispute in the foreseeable future.

Inventories

Inventories	12 Months Ended
	Dec. 31, 2021
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Inventories	11. INVENTORIES December 31 2020 (Retrospectively Adjusted) 2021 NT$ NT$ US$ (Note 4) Finished goods $ 8,822,632 $ 8,454,783 $ 304,787 Work in process 6,856,405 7,950,743 286,617 Raw materials 29,428,008 46,978,647 1,693,534 Supplies 2,691,779 3,339,042 120,369 Raw materials and supplies in transit 791,610 1,109,766 40,006 $ 48,590,434 $ 67,832,981 $ 2,445,313 The cost of inventories recognized as operating costs for the years ended December 31, 2019, 2020 and 2021 were NT$347,877,603 thousand, NT$398,068,260 thousand and NT$458,345,579 thousand (US$16,522,912 thousand), respectively, which included write-downs of inventories at NT$452,134 thousand, NT$1,493,793 thousand and NT$647,946 thousand (US$23,358 thousand), respectively.

Inventories Related to Real Est

Inventories Related to Real Estate Business	12 Months Ended
	Dec. 31, 2021
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Inventories Related to Real Estate Business	12. INVENTORIES RELATED TO REAL ESTATE BUSINESS December 31 2020 2021 NT$ NT$ US$ (Note 4) Land and buildings held for sale $ 625,791 $ 667,630 $ 24,067 Construction in progress 11,058,328 2,956,958 106,596 Land held for construction 1,787,526 1,787,526 64,439 $ 13,471,645 $ 5,412,114 $ 195,102 Construction in progress is mainly located on Hutai Road in Shanghai, China and Lidu Road in Kun Shan, China. The capitalized borrowing costs for the years ended December 31, 2019, 2020 and 2021 are disclosed in Note 25. Construction in progress located on Hutai Road in Shanghai was completed in 2021 and immediately leased out for shopping centers business wi th amount As of December 31, 2020 and 2021, inventories related to real estate business of NT$13,471,645 thousand and NT$5,412,114 thousand (US$195,102 thousand), respectively, are expected to be recovered longer than twelve months. Refer to Note 36 for the carrying amount of inventories related to real estate business that had been pledged by the Group to secure bank borrowings.

Other Financial Assets

Other Financial Assets	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Other Financial Assets	13. OTHER FINANCIAL ASSETS December 31 2020 2021 NT$ NT$ US$ (Note 4) Guarantee deposits $ 516,505 $ 1,007,651 $ 36,325 Pledged time deposits (Note 36) 367,550 415,065 14,963 Time deposits with original maturity over three months 35,988 60,499 2,181 Others (Note 36) 161,957 73,765 2,659 1,082,000 1,556,980 56,128 Current 551,655 140,857 5,078 Non-current $ 530,345 $ 1,416,123 $ 51,050

Investments Accounted for Using

Investments Accounted for Using the Equity Method	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Investments Accounted for Using the Equity Method	14. INVESTMENTS ACCOUNTED FOR USING THE EQUITY METHOD December 31 2020 2021 NT$ NT$ US$ (Note 4) Investments in associates $ 12,335,239 $ 16,500,670 $ 594,833 Investments in joint ventures 471,434 495,930 17,878 $ 12,806,673 $ 16,996,600 $ 612,711 a. Investments in associates 1) Investments in associates accounted for using the equity method that was not individually material consisted of the following: Name of Associate Main Business Operating Location Carrying Amount as of December 31 2020 2021 NT$ NT$ US$ (Note 4) Yann Yuan Investment Co., Ltd. (“Yann Yuan”) Engaged in investing activities R.O.C. $ 6,670,035 $ 9,873,978 $ 355,947 ChipMOS Technologies Inc. (“ChipMOS”) Engaged in the packaging and testing of semiconductors R.O.C. 2,406,843 2,717,250 97,954 M-Universe Investment company Singapore 1,848,588 1,859,542 67,035 Hung Ching Development & Construction Co. (“HC”) Engaged in the development, construction and leasing of real estate properties R.O.C. 1,352,760 1,828,921 65,931 Hung Ching Kwan Co. (“HCK”) Engaged in the leasing of real estate properties R.O.C. 270,087 258,757 9,328 Chipletz, Inc. (“CHIPLETZ”) Fabless substrate design house U.S.A. — 210,937 7,604 Deca Technologies Inc. (”DECA”) Holding company with group engaged in the development of wafer level packaging and interconnect technology U.S.A. 87,075 51,434 1,854 12,635,388 16,800,819 605,653 Less: Deferred gain on transfer of land 300,149 300,149 10,820 $ 12,335,239 $ 16,500,670 $ 594,833 2) At each balance sheet date, the total percentages of ownership held by the Group were as follows: December 31 2020 2021 Yann Yuan 32.21 % 29.45 % ChipMOS 10.85 % 10.85 % MU 42.23 % 42.23 % HC 26.22 % 26.22 % HCK 27.31 % 27.31 % CHIPLETZ — 20.82 % DECA 17.85 % 17.85 % 3) In March 2021, the Group’s subsidiary, ISE Labs, Inc., invested US$8,000 thousand to obtain 20.82% shareholdings in CHIPLETZ, hence, the Group has significant influence over CHIPLETZ. 4) In June 2021, the Group’s subsidiary, SPIL, did not subscribe to Yann Yuan’s cash capital increase proportionately, which led to a decrease in the Group’s percentage of ownership in Yann Yuan to 29.45%. 5) Fair values (Level 1) of investments in associates with available published price quotation are summarized as follows: December 31 2020 2021 NT$ NT$ US$ (Note 4) ChipMOS $ 2,710,572 $ 3,835,045 $ 138,250 HC $ 1,317,692 $ 2,141,249 $ 77,190 6 Aggregate information of associates that are not individually material For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) The Group’s share of: Net i ncome $ 321,413 $ 545,833 $ 872,697 $ 31,460 Other comprehensive income 1,401,453 2,784,094 3,624,403 130,656 Total comprehensive income $ 1,722,866 $ 3,329,927 $ 4,497,100 $ 162,116 b. Investments in joint ventures 1) Investment in joint ventures Name of Joint Venture Main Business Operating Location Carrying Amount as of December 31 2020 2021 NT$ NT$ US$ (Note 4) SUMA-USI (“SUMA-USI”) Engaged in the design and manufacturing of electronic products China $ 471,434 $ 495,930 $ 17,878 2) At each balance sheet date, the percentages of ownership held by the Group’s subsidiary were as follows: December 31 2020 2021 SUMA-USI 49.00% 49.00% 3) In March 2019, UGKS entered into a joint venture agreement with Cancon Information Industry Co., Ltd. to establish SUMA-USI SUMA-USI. SUMA-USI, SUMA-USI 4) Aggregate information of joint ventures that were not individually material For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) The Group’s share of: Net income $ (139,137 ) $ 1,780 $ 27,003 $ 973 Other comprehensive income (loss) (3,169 ) 3,881 — — Total comprehensive income (loss) $ (142,306 ) $ 5,661 $ 27,003 $ 973

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Property, Plant and Equipment	15. PROPERTY, PLANT AND EQUIPMENT The carrying amounts of each class of property, plant and equipment were as follows: December 31 2020 (Retrospectively Adjusted) 2021 NT$ NT$ US$ (Note 4) Land $ 10,457,960 $ 11,530,540 $ 415,665 Buildings and improvements 82,813,857 79,273,937 2,857,748 Machinery and equipment 122,539,797 128,202,516 4,621,577 Other equipment 4,700,318 3,928,284 141,610 Construction in progress and machinery under insta llatio n 13,853,465 16,932,273 610,392 $ 234,365,397 $ 239,867,550 $ 8,646,992 For the year ended December 31, 2019 Land Buildings and Machinery and Other Construction in Total NT$ NT$ NT$ NT$ NT$ NT$ Cost Balance at January 1, 2019 $ 10,165,969 $ 141,708,011 $ 353,838,390 $ 18,380,122 $ 10,911,552 $ 535,004,044 Additions — 806,844 413,008 76,671 61,777,364 63,073,887 Disposals — (983,690 ) (19,139,634 ) (2,507,440 ) — (22,630,764 ) Reclassification — 13,601,469 41,302,651 3,062,838 (57,221,627 ) 745,331 Acquisition through business combinations (Note 29) 189,111 1,044,383 5,507,315 43,611 250,455 7,034,875 Effect of foreign currency exchange differences (21,258 ) (2,204,057 ) (5,176,282 ) (300,686 ) 919,817 (6,782,466 ) Balance at December 31, 2019 $ 10,333,822 $ 153,972,960 $ 376,745,448 $ 18,755,116 $ 16,637,561 $ 576,444,907 Accumulated depreciation and impairment Balance at January 1, 2019 $ — $ 62,744,074 $ 245,750,420 $ 12,194,041 $ — $ 320,688,535 Depreciation expenses — 6,989,392 35,747,308 2,503,967 — 45,240,667 Impairment losses recognized — 78,562 102,056 20,388 — 201,006 Disposals — (881,149 ) (18,640,266 ) (2,503,438 ) — (22,024,853 ) Reclassification — 210,558 83,777 (103 ) — 294,232 Acquisition through business combinations (Note 29) — 445,682 4,000,338 19,028 — 4,465,048 Effect of foreign currency exchange differences — (1,023,739 ) (3,294,855 ) (194,461 ) — (4,513,055 ) Balance at December 31, 2019 $ — $ 68,563,380 $ 263,748,778 $ 12,039,422 $ — $ 344,351,580 For the year ended December 31, 2020 (retrospectively adjusted) Land Buildings and Machinery and Other Construction in Total NT$ NT$ NT$ NT$ NT$ NT$ Cost Balance at January 1, 2020 $ 10,333,822 $ 153,972,960 $ 376,745,448 $ 18,755,116 $ 16,637,561 $ 576,444,907 Additions — 86,409 695,561 47,137 58,195,094 59,024,201 Disposals — (365,758 ) (12,818,849 ) (2,419,423 ) (126,605 ) (15,730,635 ) Disposal of subsidiaries (Note 30) — (3,665,811 ) (3,223,448 ) (445,506 ) (792,543 ) (8,127,308 ) Reclassification — 7,367,875 52,980,977 222,066 (60,032,844 ) 538,074 Acquisitions through business combinations (Note 29) 167,136 1,680,497 4,445,789 722,490 53,828 7,069,740 Effect of foreign currency exchange differences (42,998 ) (263,672 ) (2,456,999 ) (10,902 ) (81,026 ) (2,855,597 ) Balance at December 31, 2020 (retrospectively adjusted) $ 10,457,960 $ 158,812,500 $ 416,368,479 $ 16,870,978 $ 13,853,465 $ 616,363,382 Accumulated depreciation and impairment Balance at January 1, 2020 $ — $ 68,563,380 $ 263,748,778 $ 12,039,422 $ — $ 344,351,580 Depreciation expense — 7,401,223 36,373,712 2,241,613 — 46,016,548 Impairment losses recognized — — 981,535 10,738 — 992,273 Disposals — (300,832 ) (8,306,990 ) (2,398,756 ) — (11,006,578 ) Disposal of subsidiaries (Note 30) — (153,002 ) (345,834 ) (82,059 ) — (580,895 ) Reclassification — 3,462 497,230 (188,844 ) — 311,848 Acquisitions through business combinations (Note 29) — 548,190 3,049,895 588,935 — 4,187,020 Effect of foreign currency exchange differences — (63,778 ) (2,169,644 ) (40,389 ) — (2,273,811 ) Balance at December 31, 2020 $ — $ 75,998,643 $ 293,828,682 $ 12,170,660 $ — $ 381,997,985 For the year ended December 31, 2021 Land Buildings and Machinery Other Construction in under I Total NT$ NT$ NT$ NT$ NT$ NT$ Cost Balance at January 1, 2021 (retrospectively adjusted) $ 10,457,960 $ 158,812,500 $ 416,368,479 $ 16,870,978 $ 13,853,465 $ 616,363,382 Additions 1,126,012 2,718,507 1,332,497 135,439 69,105,086 74,417,541 Disposals (2,400 ) (659,833 ) (10,999,274 ) (2,144,766 ) (32,960 ) (13,839,233 ) Disposal of subsidiaries (Note 30) — (12,344,067 ) (33,309,236 ) (1,247,326 ) (1,237,431 ) (48,138,060 ) Reclassification 393 5,038,562 53,856,444 1,181,455 (64,884,288 ) (4,807,434 ) Acquisitions through business combinations (Note 29) — 5,284 28,282 3,108 4,852 41,526 Effect of foreign currency exchange differences (51,425 ) (929,254 ) (3,788,594 ) (197,844 ) 123,549 (4,843,568 ) Balance at December 31, 2021 $ 11,530,540 $ 152,641,699 $ 423,488,598 $ 14,601,044 $ 16,932,273 $ 619,194,154 Accumulated depreciation and impairment Balance at January 1, 2021 $ — $ 75,998,643 $ 293,828,682 $ 12,170,660 $ — $ 381,997,985 Depreciation expense — 7,620,561 39,147,076 1,836,523 — 48,604,160 Impairment losses recognized — 15,915 105,815 5,036 — 126,766 Disposals — (565,551 ) (10,151,428 ) (2,065,174 ) — (12,782,153 ) Disposal of subsidiaries (Note 30) — (5,369,867 ) (24,974,206 ) (1,100,858 ) — (31,444,931 ) Reclassification — (3,924,490 ) 142,234 (18,218 ) — (3,800,474 ) Acquisitions through business combinations (Note 29) — 241 1,067 2,452 — 3,760 Effect of foreign currency exchange differences — (407,690 ) (2,813,158 ) (157,661 ) — (3,378,509 ) Balance at December 31, 2021 $ — $ 73,367,762 $ 295,286,082 $ 10,672,760 $ — $ 379,326,604 Land Buildings and Machinery Other Construction in under I Total US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Cost Balance at January 1, 2021 ( re tr o spectively adjusted) $ 376,999 $ 5,725,036 $ 15,009,678 $ 608,182 $ 499,404 22,219,299 Additions 40,592 98,000 48,035 4,883 2,491,171 2,682,681 Disposals (86 ) (23,786 ) (396,513 ) (77,317 ) (1,188 ) (498,890 ) Disposal of subsidiaries (Note 30) — (444,992 ) (1,200,765 ) (44,965 ) (44,608 ) (1,735,330 ) Reclassification 14 181,635 1,941,473 42,590 (2,339,016 ) (173,304 ) Acquisitions through business combinations (Note 29) — 190 1,020 112 175 1,497 Effect of foreign currency exchange differences (1,854 ) (33,499 ) (136,575 ) (7,132 ) 4,454 (174,606 ) Balance at December 31, 2021 $ 415,665 $ 5,502,584 $ 15,266,353 $ 526,353 $ 610,392 $ 22,321,347 Accumulated depreciation and impairment Balance at January 1, 2021 $ — $ 2,739,677 $ 10,592,238 $ 438,740 $ — $ 13,770,655 Depreciation expense — 274,714 1,411,214 66,205 — 1,752,133 Impairment losses recognized — 574 3,815 182 — 4,571 Disposals — (20,388 ) (365,949 ) (74,447 ) — (460,784 ) Disposal of subsidiaries (Note 30) — (193,579 ) (900,296 ) (39,685 ) — (1,133,560 ) Reclassification — (141,474 ) 5,127 (657 ) — (137,004 ) Acquisitions through business combinations (Note 29) — 9 39 89 — 137 Effect of foreign currency exchange differences — (14,697 ) (101,412 ) (5,684 ) — (121,793 ) Balance at December 31, 2021 $ — $ 2,644,836 $ 10,644,776 $ 384,743 $ — $ 13,674,355 Based on the future operation plans and the capacity evaluation, the Group assessed that a portion of plant and equipment in the packaging segment and the testing segment were not qualified for the production needs and, therefore, recognized an impairment loss of NT$201,006 thousand, NT$992,273 thousand and NT$126,766 thousand (US$4,571 thousand) under the line item of other operating income and expenses (Note 25) for the years ended December 31, 2019, 2020 and 2021, respectively. The recoverable amounts of a portion of the impaired plant and equipment were determined by their fair value less cost of disposal, of which the fair value was based on the recent quoted prices of assets with similar age and obsolescence provided by vendors in secondary market or the disposal price, and both of which represented Level 3 inputs because the secondary market was not active and the disposal price was negotiated with counterparties. The recoverable amounts of the remaining impaired plant and equipment were determined by their value in use and the Group expects only short-term or no economic benefits would be generated by these assets and the discount effect was immaterial. Each class of property, plant and equipment was depreciated on a straight-line basis over the following useful lives: Buildings and improvements Main plant buildings 10-55 years Cleanrooms 10-20 years Others 3-20 years Machinery and equipment 2-10 years Other equipment 2-20 years The capitalized borrowing costs for the years ended December 31, 2019, 2020 and 2021 are disclosed in Note 25.

Lease Arrangements

Lease Arrangements	12 Months Ended
	Dec. 31, 2021
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Lease Arrangements	16. LEASE ARRANGEMENTS a. Right-of-use December 31 2020 (Retrospectively Adjusted) 2021 NT$ NT$ US$ (Note 4) Carrying amounts Land $ 5,961,974 $ 6,093,518 $ 219,666 Buildings and improvements 2,548,838 3,663,682 132,072 Machinery and equipment 181,065 880,443 31,739 Other equipment 49,930 42,619 1,536 $ 8,741,807 $ 10,680,262 $ 385,013 For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Additions to right-of-use $ 824,268 $ 702,996 $ 3,239,770 $ 116,791 Depreciation charge for right-of-use $ 215,301 $ 214,682 $ 217,674 $ 7,847 Land 307,708 370,458 509,746 18,376 Buildings and improvements Machinery and equipment 507,443 335,039 356,052 12,835 Other equipment 25,006 26,701 31,478 1,135 $ 1,055,458 $ 946,880 $ 1,114,950 $ 40,193 The amounts disclosed above with respect to the right-of-use right-of-use b. Lease liabilities December 31 2020 2021 NT$ NT$ US$ (Note 4) Carrying amounts Current $ 774,444 $ 809,536 $ 29,183 Non-current $ 5,101,386 $ 6,590,348 $ 237,576 The Group’s lease liabilities were mainly from land and buildings and improvements. The range of discount rates for lease liabilities was as follows: December 31 2020 2021 Land (%) 0.54-8.00 0.54-8.00 Buildings and improvements (%) 0.54-8.84 0.45-8.84 c. Material lease-in The Group leases land and buildings for the use of plants and offices with remaining lease terms of 1-53 1-29 d. Subleases In addition to the sublease transactions described in Note 17, the Group did not have other sublease transactions. e. Other lease information December 31 2020 2021 NT$ NT$ US$ (Note 4) Expenses relating to short-term leases $ 682,142 $ 814,235 $ 29,352 Expenses relating to low-value $ 5,433 $ 5,080 $ 183 Expenses relating to variable lease payments not included in the measurement of lease liabilities $ 43,112 $ 61,141 $ 2,204 Total cash outflow for leases $ 1,854,456 $ 2,909,157 $ 104,872 The Group elected to apply the recognition exemption for qualifying short-term leases and low-value ther ef right-of-use

Investment Properties

Investment Properties	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Investment Properties	17. INVESTMENT PROPERTIES For the year ended December 31, 2019 Land Buildings and Right-of-use Total NT$ NT$ NT$ NT$ Cost Balance at January 1, 2019 $ 35,965 $ 8,409,790 $ 6,891,947 $ 15,337,702 Additions — 2,532 — 2,532 Disposals — (1,843 ) — (1,843 ) Reclassification — (490,130 ) (21,069 ) (511,199 ) Effects of foreign currency exchange differences — (209,980 ) (303,086 ) (513,066 ) Balance at December 31, 2019 $ 35,965 $ 7,710,369 $ 6,567,792 $ 14,314,126 Accumulated depreciation Balance at January 1, 2019 $ — $ 707,376 $ 292,722 $ 1,000,098 Depreciation expenses — 377,536 216,574 594,110 Disposals — (1,240 ) — (1,240 ) Reclassification — (210,455 ) 543 (209,912 ) Effects of foreign currency exchange differences — 99,354 (22,355 ) 76,999 Balance at December 31, 2019 $ — $ 972,571 $ 487,484 $ 1,460,055 Carrying amount at December 31, 2019 $ 35,965 $ 6,737,798 $ 6,080,308 $ 12,854,071 For the year ended December 31, 2020 Land Buildings and Right-of-use Total NT$ NT$ NT$ NT$ Cost Balance at January 1, 2020 $ 35,965 $ 7,710,369 $ 6,567,792 $ 14,314,126 Additions — 6,352 — 6,352 Disposals — (1,902 ) — (1,902 ) Reclassification — (3,884 ) 46,201 42,317 Effects of foreign currency exchange differences — 111,870 124,920 236,790 Balance at December 31, 2020 $ 35,965 $ 7,822,805 $ 6,738,913 $ 14,597,683 Accumulated depreciation Balance at January 1, 2020 $ — $ 972,571 $ 487,484 $ 1,460,055 Depreciation expenses — 353,048 209,212 562,260 Disposals — (1,293 ) — (1,293 ) Reclassification — (1,498 ) 10,617 9,119 Effects of foreign currency exchange differences — 19,639 9,820 29,459 Balance at December 31, 2020 $ — $ 1,342,467 $ 717,133 $ 2,059,600 Carrying amount at December 31, 2020 $ 35,965 $ 6,480,338 $ 6,021,780 $ 12,538,083 For the year ended December 31, 2021 Land Buildings and Right-of-use Total NT$ NT$ NT$ NT$ Cost Balance at January 1, 2021 $ 35,965 $ 7,822,805 $ 6,738,913 $ 14,597,683 Disposals — (5,350 ) — (5,350 ) Disposal of subsidiaries (Note 30) — (1,290,187 ) (87,412 ) (1,377,599 ) Reclassification (Note 12) (393 ) 9,818,133 3,398,139 13,215,879 Effects of foreign currency exchange differences 0 30,697 (6,962 ) 23,735 Balance at December 31, 2021 $ 35,572 $ 16,376,098 $ 10,042,678 $ 26,454,348 Accumulated depreciation Balance at January 1, 2021 $ — $ 1,342,467 $ 717,133 $ 2,059,600 Depreciation expenses — 482,625 268,422 751,047 Disposals — (3,671 ) — (3,671 ) Disposal of subsidiaries (Note 30) — (570,403 ) (19,946 ) (590,349 ) Reclassification — 2,014,201 78,914 2,093,115 Effects of foreign currency exchange differences — 6,927 (7,108 ) (181 ) Balance at December 31, 2021 $ — $ 3,272,146 $ 1,037,415 $ 4,309,561 Carrying amount at December 31, 2021 $ 35,572 $ 13,103,952 $ 9,005,263 $ 22,144,787 Land Buildings and Right-of-use Total US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Cost Balance at January 1, 2021 $ 1,296 $ 282,005 $ 242,931 $ 526,232 Disposals — (193 ) — (193 ) Disposal of subsidiaries (Note 30) — (46,510 ) (3,151 ) (49,661 ) Reclassification (Note 12) (14 ) 353,934 122,500 476,420 Effects of foreign currency exchange differences — 1,107 (251 ) 856 Balance at December 31, 2021 $ 1,282 $ 590,343 $ 362,029 $ 953,654 Accumulated depreciation Balance at January 1, 2021 $ — $ 48,395 $ 25,852 $ 74,247 Depreciation expenses — 17,398 9,676 27,074 Disposals — (132 ) — (132 ) Disposal of subsidiaries (Note 30) — (20,563 ) (719 ) (21,282 ) Reclassification — 72,610 2,845 75,455 Effects of foreign currency exchange differences — 250 (256 ) (6 ) Balance at December 31, 2021 $ — $ 117,958 $ 37,398 $ 155,356 Carrying amount at December 31, 2021 $ 1,282 $ 472,385 $ 324,631 $ 798,298 Right-of-use The abovementioned investment properties were leased out for 1 to 20 years, with an option to extend for an additional lease term. The lease contracts contain market review clauses in the event that the lessees exercise their options to extend. The lessees do not have bargain purchase In addition to fixed lease payments, some of the lease contracts also indicated that the lessees should make variable payments determined at a specific percentage of the excess of respective lessee’s monthly revenues over a specific amount. The maturity analysis of lease payments receivable under operating leases of investment properties was as follows: December 31 2020 2021 NT$ NT$ US$ (Note 4) Year 1 $ 880,929 $ 1,693,659 $ 61,055 Year 2 688,123 1,405,450 50,666 Year 3 471,966 1,210,891 43,651 Year 4 383,307 1,019,498 36,752 Year 5 335,706 929,609 33,511 Year 6 onwards 664,259 3,241,525 116,854 $ 3,424,290 $ 9,500,632 $ 342,489 The investment properties were depreciated on a straight-line basis over the following useful lives: Main buildings 10-40 years Right-of-use 10-50 years Because the market conditions we re COVID-19 concessions The fair value of the investment properties was measured using the market approach and the income approach based on level 3 inputs by independent professional appraisers. The significant unobservable inputs were discount rates. The fair value of the investment properties was as follows: December 31 2020 2021 NT$ NT$ US$ (Note 4) Fair value $ 19,799,714 $ 36,158,216 $ 1,303,468 Refer to Note 36 for the carrying amount of the investment properties that had been pledged by the Group to secure borrowings.

Goodwill

Goodwill	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Goodwill	18. GOODWILL For the year ended December 31, 2019 Cost Accumulated Carrying NT$ NT$ NT$ Balance at January 1, 2019 $ 52,388,559 $ 2,414,113 $ 49,974,446 Acquisition through business combinations (Note 29) 264,977 — 264,977 Effect of foreign currency exchange differences (40,987 ) — (40,987 ) Balance at December 31, 2019 $ 52,612,549 $ 2,414,113 $ 50,198,436 For the year ended December 31, 2020 (retrospectively adjusted) Cost Accumulated Carrying NT$ NT$ NT$ Balance at January 1, 2020 $ 52,612,549 $ 2,414,113 $ 50,198,436 Acquisition through business combinations (Note 29) 2,567,842 — 2,567,842 Effect of foreign currency exchange differences (57,225 ) — (57,225 ) Balance at December 31, 2020 $ 55,123,166 $ 2,414,113 $ 52,709,053 For the year ended December 31, 2021 Cost Accumulated Carrying NT$ NT$ NT$ Balance at January 1, 2021 (retrospectively adjusted) $ 55,123,166 $ 2,414,113 $ 52,709,053 Disposal of subsidiaries (Note 30) (310,711 ) — (310,711 ) Effect of foreign currency exchange differences (325,929 ) — (325,929 ) Balance at December 31, 2021 $ 54,486,526 $ 2,414,113 $ 52,072,413 Cost Accumulated Carrying US$ (Note 4) US$ (Note 4) US$ (Note 4) Balance at January 1, 2021 (re tro adjusted) $ 1,987,136 $ 87,026 $ 1,900,110 Disposal of subsidiaries (Note 30) (11,201 ) — (11,201 ) Effect of foreign currency exchange differences (11,749 ) — (11,749 ) Balance at December 31, 2021 $ 1,964,186 $ 87,026 $ 1,877,160 a. Allocating goodwill to cash-generating units The Group did not monitor goodwill for internal management purpose but for financial reporting purpose and, therefore, the goodwill was allocated to the following cash-generating units for evaluation of impairment: packaging segment, testing segment, EMS segment and other segment. The carrying amounts of goodwill allocated to cash-generating units were as follows: December 31 2020 (Retrospectively 2021 Cash-generating units NT$ NT$ US$ (Note 4) Packaging segment $ 35,703,625 $ 35,412,424 $ 1,276,583 Testing segment 13,365,068 13,304,040 479,598 EMS segment (Note 29) 3,492,259 3,207,848 115,640 Others 148,101 148,101 5,339 $ 52,709,053 $ 52,072,413 $ 1,877,160 b. Impairment assessment At the end of each year, the Group performs evaluation of goodwill for impairment by reviewing the recoverable amounts based on value in use which incorporates cash flow projections estimated by management covering a five-year period. The cash flows beyond that five-year period are extrapolated using a steady per annum growth rate. In assessing value in use, the estimated future cash flows are discounted to their present value using annual pre-tax Management believes that any reasonably possible change in the key assumptions on which the recoverable amount was based on the each

Other Intangible Assets

Other Intangible Assets	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Other Intangible Assets	19. OTHER INTANGIBLE ASSETS The carrying amounts of each class of other intangible assets were as follows: December 31 2020 (Retrospectively Adjusted) 2021 NT$ NT$ US$ (Note 4) Customer relationships $ 9,120,300 $ 7,990,956 $ 288,066 Computer software 2,795,873 2,779,723 100,206 Patents and acquired specific technology 15,720,213 13,730,404 494,968 Others 75,385 62,624 2,258 $ 27,711,771 $ 24,563,707 $ 885,498 For the year ended December 31, 2019 Customer Computer Patents and Others Total NT$ NT$ NT$ NT$ NT$ Cost Balance at January 1, 2019 $ 11,915,636 $ 4,401,045 $ 20,588,356 $ 83,657 $ 36,988,694 Additions — 1,358,533 — (7,625 ) 1,350,908 Disposals or derec o tion (915,635 ) (1,123,446 ) — (6,315 ) (2,045,396 ) Acquisition through business combinations (Note 29) — 19,944 732,604 — 752,548 Effect of foreign currency exchange differences — (49,198 ) (2,264 ) (1,417 ) (52,879 ) Balance at December 31, 2019 $ 11,000,001 $ 4,606,878 $ 21,318,696 $ 68,300 $ 36,993,875 Accumulated amortization Balance at January 1, 2019 $ 1,548,839 $ 3,241,363 $ 1,332,687 $ 27,772 $ 6,150,661 Amortization expense 1,033,464 583,300 1,955,703 4,139 3,576,606 Disposals or derecognization (915,635 ) (1,116,512 ) — (6,315 ) (2,038,462 ) Acquisition through business combinations (Note 29) — 7,765 313,422 — 321,187 Effect of foreign currency exchange differences — (38,577 ) (1,639 ) (293 ) (40,509 ) Balance at December 31, 2019 $ 1,666,668 $ 2,677,339 $ 3,600,173 $ 25,303 $ 7,969,483 For the year ended December 31, 2020 (retrospectively adjusted) Customer Computer Patents and Others Total NT$ NT$ NT$ NT$ NT$ Cost Balance at January 1, 2020 $ 11,000,001 $ 4,606,878 $ 21,318,696 $ 68,300 $ 36,993,875 Additions — 951,439 171 31,045 982,655 Disposals or derecognization — (55,413 ) — (14,594 ) (70,007 ) Disposal of subsidiaries (Note 30) — (38,125 ) — — (38,125 ) Acquisition through business combinations (Note 29) 885,565 1,567,508 — 114,269 2,567,342 Effect of foreign currency exchange differences 4,717 (65,838 ) 312 (19,160 ) (79,969 ) Balance at December 31, 2020 $ 11,890,283 $ 6,966,449 $ 21,319,179 $ 179,860 $ 40,355,771 Accumulated amortization Balance at January 1, 2020 $ 1,666,668 $ 2,677,339 $ 3,600,173 $ 25,303 $ 7,969,483 Amortization expense 1,000,000 729,330 1,998,554 5,493 3,733,377 Disposals or derecognization — (47,345 ) — (5,044 ) (52,389 ) Disposal of subsidiaries (Note 30) — (10,688 ) — — (10,688 ) Acquisition through business combinations (Note 29) 102,768 843,746 — 79,673 1,026,187 Effect of foreign currency exchange differences 547 (21,806 ) 239 (950 ) (21,970 ) Balance at December 31, 2020 $ 2,769,983 $ 4,170,576 $ 5,598,966 $ 104,475 $ 12,644,000 For the year ended December 31, 2021 Customer Computer Patents and Others Total NT$ NT$ NT$ NT$ NT$ Cost Balance at January 1, 2021 (retrospectively adjusted) $ 11,890,283 $ 6,966,449 $ 21,319,179 $ 179,860 $ 40,355,771 Additions — 1,193,060 2,000 37,959 1,233,019 Disposals or derecognization (102,637 ) (150,670 ) — (71,014 ) (324,321 ) Disposal of subsidiaries (Note 30) — (789,998 ) (5,401 ) (6,243 ) (801,642 ) Acquisition through business combinations (Note 29) — 622 — — 622 Effect of foreign currency exchange differences (83,041 ) (167,769 ) (537 ) (7,036 ) (258,383 ) Balance at December 31, 2021 $ 11,704,605 $ 7,051,694 $ 21,315,241 $ 133,526 $ 40,205,066 Accumulated amortization Balance at January 1, 2021 $ 2,769,983 $ 4,170,576 $ 5,598,966 $ 104,475 $ 12,644,000 Amortization expense 1,049,759 971,190 1,991,641 41,530 4,054,120 Disposals or derecognization (102,637 ) (139,907 ) — (67,741 ) (310,285 ) Disposal of subsidiaries (Note 30) — (626,338 ) (5,288 ) (3,067 ) (634,693 ) Acquisition through business combinations (Note 29) — 222 — — 222 Effect of foreign currency exchange differences (3,456 ) (103,772 ) (482 ) (4,295 ) (112,005 ) Balance at December 31, 2021 $ 3,713,649 $ 4,271,971 $ 7,584,837 $ 70,902 $ 15,641,359 Customer Computer Patents and Others Total US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Cost Balance at January 1, 2021 (retrospectively adjusted) $ 428,633 $ 251,134 $ 768,536 $ 6,484 $ 1,454,787 Additions — 43,009 72 1,368 44,449 Disposals or derecognization (3,700 ) (5,432 ) — (2,560 ) (11,692 ) Disposal of subsidiaries (Note 30) — (28,479 ) (195 ) (225 ) (28,899 ) Acquisition through business combinations (Note 29) — 23 — — 23 Effect of foreign currency exchange differences (2,994 ) (6,048 ) (19 ) (254 ) (9,315 ) Balance at December 31, 2021 $ 421,939 $ 254,207 $ 768,394 $ 4,813 $ 1,449,353 Accumulated amortization Balance at January 1, 2021 $ 99,855 $ 150,345 $ 201,837 $ 3,766 $ 455,803 Amortization expense 37,843 35,010 71,797 1,497 146,147 Disposals or derecognization (3,700 ) (5,043 ) — (2,442 ) (11,185 ) Disposal of subsidiaries (Note 30) — (22,579 ) (191 ) (110 ) (22,880 ) Acquisition through business combinations (Note 29) — 8 — — 8 Effect of foreign currency exchange differences (125 ) (3,741 ) (17 ) (155 ) (4,038 ) Balance at December 31, 2021 $ 133,873 $ 154,000 $ 273,426 $ 2,556 $ 563,855 Each class of other intangible assets was amortized on the straight-line basis over the following useful lives: December 31, December 31, 2021 Customer relationships 11-16 years 11-16 years Computer software 2-10 years 2-10 years Patents and acquired specific technology 5-17 years 5-17 years Others 5-32 years 5-10 years

Borrowings

Borrowings	12 Months Ended
	Dec. 31, 2021
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Borrowings	20. BORROWINGS a. Short-term borrowings Bank loans mainly represented unsecured revolving loans , a nd bank overdrafts. December 31 2020 2021 NT$ NT$ US$ (Note 4) Secured bank loans, annual interest rates both were 0.90%-1.87% as of December 31, 2020 and 2021 $ 300,495 $ 203,127 $ 7,322 Unsecured bank loans, annual interest rates were 0.58%-3.38% 0.40%-3.75% 34,297,362 40,833,302 1,472,001 34,597,857 41,036,429 1,479,323 Less: financial liabilities for hedging - current (Note 34) 3,307,018 6,716,965 242,140 $ 31,290,839 $ 34,319,464 $ 1,237,183 b. Long-term borrowings 1) Bank loans December 31 2020 2021 NT$ NT$ US$ (Note 4) Revolving bank loans Syndicated bank loans - repayable through January 2022, annual interest rates were 1.15%-1.17% and 1.08% as of December 31, 2020 and 2021, respectively (Note 36) $ 12,536,424 $ 2,562,926 $ 92,391 Others - repayable through January 2022 to July 2029, annual interest rates were 0.56%-4.15% and 0.40%-4.00% as of December 31, 2020 and 2021, respectively 84,146,125 107,383,417 3,871,068 Mortgage loans Repayable through March 2022 to December 2033, annual interest rates were 1.90%-4.90% and 2.32%-4.55% as of December 31, 2020 and 2021, respectively 10,813,997 8,031,142 289,515 107,496,546 117,977,485 4,252,974 Less: unamortized discounts 104,323 3,642 131 107,392,223 117,973,843 4,252,843 Less: current portion 2,250,121 4,526,683 163,183 financial liabilities for hedging - current (Note 34) 1,970,307 — — financial liabilities for hedging - non-current (Note 34) 5,910,919 4,780,931 172,348 $ 97,260,876 $ 108,666,229 $ 3,917,312 Pursuant to some of the above revolving bank loans agreements, the Company’s subsidiaries should meet certain financial covenants which are calculated based on each of their annual audited consolidated financial statements or semi-annual reviewed consolidated financial statements. The Company’s subsidiaries were in compliance with all of the financial covenants. 2) Long-term bills payable December 31 2020 2021 NT$ NT$ US$ (Note 4) China Bills Finance Corporation, repayable through March 2023 to December 2023, annual interest rates were 0.65%-0.90% and 0.65% as of December 31, 2020 and 2021, respectively $ 2,000,000 $ 2,500,000 $ 90,123 December 31 2020 2021 NT$ NT$ US$ (Note 4) Ta Ching Bills Finance Corporation, repayable through January 2023 to March 2023, annual interest rates were 0.91% and 0.65% as of December 31, 2020 and 2021, respectively $ 1,000,000 $ 2,500,000 $ 90,123 Mega Bills Finance Corporation, repayable in March 2023, annual interest rates were 0.92%-0.93% and 0.65% as of December 31, 2020 and 2021, respectively 2,000,000 2,000,000 72,098 International Bills Finance Corporation, early repaid in March 2023, annual interest rate was 0.65% as of December 31, 2021 — 1,500,000 54,073 5,000,000 8,500,000 306,417 Less: unamortized discounts 1,498 1,353 49 $ 4,998,502 $ 8,498,647 $ 306,368

Bonds Payable

Bonds Payable	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Bonds Payable	21. BONDS PAYABLE December 31 2020 2021 NT$ NT$ US$ (Note 4) Unsecured domestic bonds Interest due annually with annual interest rate at 1.30% and fully redeemed in January 2021 $ 7,000,000 $ — $ — Repayable at maturity in January 2023 and interest due annually with annual interest rate at 1.50% 2,000,000 2,000,000 72,098 Repayable at maturity in January 2022 and interest due annually with annual interest rate at 1.25% 3,700,000 3,700,000 133,381 Repayable at maturity in January 2024 and interest due annually with annual interest rate at 1.45% 4,300,000 4,300,000 155,011 Repayable at maturity in April 2024 and interest due annually with annual interest rate at 0.90% 6,500,000 6,500,000 234,319 Repayable at maturity in April 2026 and interest due annually with annual interest rate at 1.03% 3,500,000 3,500,000 126,172 Repayable at maturity in April 2025 and interest due annually with annual interest rate at 0.90% 10,000,000 10,000,000 360,490 Repayable at maturity in August 2023 and interest due annually with annual interest rate at 0.72% 3,000,000 3,000,000 108,147 Repayable at maturity in August 2025 and interest due annually with annual interest rate at 0.85% 5,000,000 5,000,000 180,245 Repayable at maturity in August 2027 and interest due annually with annual interest rate at 0.95% 2,000,000 2,000,000 72,098 Unsecured overseas bonds US$200,000 thousand (linked to New Taiwan dollar), repayable at maturity in October 2022 and interest due quarterly with annual interest rate at 2.15% 6,204,800 6,204,800 223,677 US$100,000 thousand (linked to New Taiwan dollar), repayable at maturity in October 2024 and interest due quarterly with annual interest rate at 2.50% 3,102,400 3,102,400 111,839 Unsecured overseas convertible bonds RMB779,801 thousand, repayable at maturity in March 2027 and interest due annually with annual interest rate at 0.10%, 0.20%, 0.60%, 1.30%, 1.80% and 2.00% for the first, second, third, fourth, fifth and sixth year, respectively — 3,385,381 122,040 56,307,200 52,692,581 1,899,517 Less: discounts on bonds payable 53,646 425,244 15,330 56,253,554 52,267,337 1,884,187 Less: current portion of bonds payable 6,999,951 9,902,710 356,983 $ 49,253,603 $ 42,364,627 $ 1,527,204 a. In December 2017, AMPI offered the fifth secured domestic convertible bonds in NT$250,000 thousand with nil coupon rate and a maturity of 3 years. Each holder of the bonds has the right to convert the bonds into ordinary shares of AMPI at the conversion price at any time from the 3 months after the offering date to the maturity date. The initial conversion price was NT$4.8 per share at offering date and the conversion price will be subject to adjustment in the event of the conversion provisions due to anti-dilution clause. As of September 30, 2020, the conversion prices was NT$4.8 per share. The bonds may be early redeemed at the option of AMPI, in whole or in part, at any time provided that (1) if the closing price of AMPI’s ordinary shares on the Taipei Exchange exceeds the conversion price by 30% or more for 30 consecutive business days in the period starting from 3 months after the offering to 40 days before the maturity or (2) the outstanding amount of the bonds falls below 10% of the originally offered in the period aforementioned. AMPI already redeemed these bonds in December 2020. b. In March 2021, the subsidiary, USISH, offered an unsecured overseas convertible bonds (the “USISH Bonds”) in RMB3,450,000 thousand with par value of RMB100. Within 5 trading days after maturity, USISH will redeem all the unconverted bonds at a price of 108% of the par value (including the interests of installation When the USISH Bonds were offered, the subsidiaries, USIE and ASE (Shanghai) Inc., totally subscribed for RMB2,670,199 thousand. Such USISH Bonds were deemed as a hybrid financial instrument under IFRS 9 and, therefore, USIE and ASE (Shanghai) Inc. classified them as financial assets mandatorily at FVTPL. Since the aforementioned contractual obligations assumed by USISH and the contractual rights entitled to USIE and ASE (Shanghai) Inc. were extinguished in economic substance, the assets and liabilities related to the USISH Bonds subscribed for by USIE and ASE (Shanghai) Inc. were all Each holder of the USISH Bonds has the right to convert the USISH Bonds into ordinary shares of USISH at the conversion price at any time from the first trading day after 9 months of the offering date to the maturity date (the “Conversion Period”). The initial conversion price was RMB20.25 per share at offering date and the conversion price will be subject to the adjustment in the event of the conversion provisions due to anti-dilution clause. As of December 31, 2021, the conversion price was RMB19.75. As of December 31, 2021, USISH Bonds with the cumulative par value of RMB26 thousand was converted into one thousand ordinary shares of USISH. Before the maturity of the Bonds, if the closing price of USISH’s ordinary shares in Shanghai Stock Exchange is lower than 80% of the current conversion price for at least 15 trading days out of any 30 consecutive trading days, the board of directors of USISH will have the right to propose a downward revision on conversion price and submit it to USISH’s shareholders’ meeting for approval. During the Conversion Period, USISH’s board of directors has the right to redeem all or part of the unconverted bonds at the price of par value plus accrued interests in either of the following circumstances: (1) if the closing price of USISH’s ordinary shares in Shanghai Stock Exchange is not less 130% (including 130%) of the current conversion price for at least 20 trading days out of any 30 consecutive trading days, or (2) the unconverted USISH Bonds falls below RMB30,000 thousand. In the last two interest accrual years before the maturity, the holders of USISH Bonds have the right to sell back all or part of USISH Bonds to USISH at the price of par value plus accrued interest in either of the following circumstances: (1) if the closing price of USISH’s ordinary shares in Shanghai Stock Exchange is lower than 70% of the current conversion price in any 30 consecutive trading days, or (2) if USISH is deemed to change the use of the funds pursuant to the relevant regulations of the China Securities Regulatory Commission or USISH is identified by the China Securities Regulatory Commission as changing the use of funds before the maturity. In addition, after 3 years from the offering date, holders of USISH Bonds have the right to sell back all or part of USISH Bonds to USISH at 102% of the par value (including the interests accrued for the 3rd year). At the offering date, USISH Bonds consisted of debt host contract (recognized under the line item of bonds payable), conversion right (recognized under the line item of non-controlling con versi on

Other Payables

Other Payables	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Other Payables	22. OTHER PAYABLES December 31 2020 2021 NT$ NT$ US$ (Note 4) Payables for property, plant and equipment $ 10,013,971 $ 13,607,664 $ 490,543 Accrued salary and bonus 12,448,548 12,217,011 440,411 Accrued employees’ compensation and remuneration to directors 4,405,981 7,711,445 277,990 Accrued employee insurance 1,105,122 1,204,387 43,417 Accrued utilities 536,491 581,662 20,968 Others 10,905,510 11,374,731 410,049 $ 39,415,623 $ 46,696,900 $ 1,683,378

Retirement Benefit Plans

Retirement Benefit Plans	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Retirement Benefit Plans	23. RETIREMENT BENEFIT PLANS a. Defined contribution plans 1) The pension plan under the R.O.C. Labor Pension Act (“LPA”) for the Group’s R.O.C. resident employees is a government-managed defined contribution plan. Based on the LPA, the Company and its subsidiaries in R. O.C . 2) The subsidiaries of the Group located in countries other than Taiwan also make contributions at various ranges according to relevant local regulations. b. Defined benefit plans 1) The Company and its subsidiaries in R.O.C . R .O.C . R.O.C . R.O.C . Taiwan 2) Pension plans for certain subsidiaries of the Group stipulate that employees with service years exceeding agreed years are entitled to receive a lump-sum 3) ASE, SPIL, ASE Test, Inc. and ASEE have ies were 4) The amounts included in the consolidated balance sheets arising from the Group’s obligation in respect of its defined benefit plans excluding those for executive managers were as follows: December 31 2020 2021 NT$ NT$ US$ (Note 4) Present value of the defined benefit obligation $ 12,159,145 $ 11,424,860 $ 411,855 Fair value of the plan assets (5,962,305 ) (5,863,264 ) (211,365 ) Present value of unfunded defined benefit obligation 6,196,840 5,561,596 200,490 Recorded under other payables (102,367 ) (67,524 ) (2,434 ) Recorded under other non-current 26,306 — — Net defined benefit liabilit ies $ 6,120,779 $ 5,494,072 $ 198,056 Movements in net defined benefit liabilit ies Present Value of the Defined Fair Value of Net Defined Liabilit ies s NT$ NT$ NT$ Balance at January 1, 2019 $ 10,297,139 $ (5,492,123 ) $ 4,805,016 Service cost Current service cost 211,226 — 211,226 Net interest expense (income) 151,635 (97,387 ) 54,248 Recognized in profit or loss 362,861 (97,387 ) 265,474 Remeasurement Return on plan assets (excluding amounts included in net interest) — (104,516 ) (104,516 ) Actuarial (gain) loss Changes in financial assumptions 398,732 — 398,732 Experience adjustments 70,374 — 70,374 Changes in demographic assumptions (2,329 ) — (2,329 ) Recognized in other comprehensive income 466,777 (104,516 ) 362,261 Contributions from the employer — (514,617 ) (514,617 ) Benefits paid from the pension fund (393,897 ) 393,897 — the Group (21,439 ) — (21,439 ) Business combinations 62,857 (28,380 ) 34,477 Exchange differences on foreign plans (105,724 ) 100,948 (4,776 ) Balance at December 31, 2019 10,668,574 (5,742,178 ) 4,926,396 Service cost Current service cost 193,693 — 193,693 Past service cost and gain on settlements (25,891 ) — (25,891 ) Net interest expense (income) 119,314 (81,114 ) 38,200 Recognized in profit or loss 287,116 (81,114 ) 206,002 Remeasurement Return on plan assets (excluding amounts included in net interest) — (109,616 ) (109,616 ) Actuarial (gain) loss Changes in financial assumptions 465,433 — 465,433 Experience adjustments 281,661 — 281,661 Changes in demographic assumptions (36,627 ) — (36,627 ) Recognized in other comprehensive income 710,467 (109,616 ) 600,851 Present Value of the Defined Fair Value of Net Defined Liabilit ies s NT$ NT$ NT$ Contributions from the employer $ — $ (620,433 ) $ (620,433 ) Benefits paid from the pension fund (552,430 ) 603,137 50,707 the Group (14,520 ) — (14,520 ) Assets extinguished on settlement — 11,910 11,910 Business combinations 1,018,480 — 1,018,480 Exchange differences on foreign plans 41,458 (24,011 ) 17,447 Balance at December 31, 2020 12,159,145 (5,962,305 ) 6,196,840 Service cost Current service cost 173,307 — 173,307 Past service cost and gain on settlements (10,284 ) — (10,284 ) Net interest expense (income) 78,501 (59,761 ) 18,740 Recognized in profit or loss 241,524 (59,761 ) 181,763 Remeasurement Return on plan assets (excluding amounts included in net interest) — (42,636 ) (42,636 ) Actuarial (gain) loss Changes in financial assumptions (418,542 ) — (418,542 ) Experience adjustments 242,896 — 242,896 Changes in demographic assumptions 160,156 — 160,156 Recognized in other comprehensive income (15,490 ) (42,636 ) (58,126 ) Contributions from the employer — (542,584 ) (542,584 ) Benefits paid from the pension fund (556,419 ) 562,442 6,023 the Group (80,603 ) — (80,603 ) Business combinations 46,291 — 46,291 Exchange differences on foreign plans (369,588 ) 181,580 (188,008 ) Balance at December 31, 2021 $ 11,424,860 $ (5,863,264 ) $ 5,561,596 Present Value of the Defined Fair Value of Net Defined Liabilit ies s US$ (Note 4) US$ (Note 4) US$ (Note 4) Balance at January 1, 2021 $ 438,325 $ (214,935 ) $ 223,390 Service cost Current service cost 6,248 — 6,248 Past service cost and gain on settlements (371 ) — (371 ) Net interest expense (income) 2,830 (2,154 ) 676 Recognized in profit or loss 8,707 (2,154 ) 6,553 Remeasurement Return on plan assets (excluding amounts included in net interest) — (1,537 ) (1,537 ) Actuarial (gain) loss Changes in financial assumptions (15,088 ) — (15,088 ) Experience adjustments 8,756 — 8,756 Changes in demographic assumptions 5,773 — 5,773 Recognized in other comprehensive income (559 ) (1,537 ) (2,096 ) Contributions from the employer — (19,560 ) (19,560 ) Benefits paid from the pension fund (20,058 ) 20,275 217 the Group (2,906 ) — (2,906 ) Business combinations 1,669 — 1,669 Exchange differences on foreign plans (13,323 ) 6,546 (6,777 ) Balance at December 31, 2021 $ 411,855 $ (211,365 ) $ 200,490 5) The fair value of the plan assets by major categories at each balance sheet date was as follows: December 31 2020 2021 NT$ NT$ US$ (Note 4) Cash $ 2,236,340 $ 2,267,223 $ 81,731 Equity instruments 2,459,708 2,334,180 84,145 Debt instruments 1,092,115 1,039,412 37,470 Others 174,142 222,449 8,019 Total $ 5,962,305 $ 5,863,264 $ 211,365 6) Through the defined benefit plans under the Labor Standards Law of the R.O.C., the Group in R. O.C . a) Investment risk The plan assets are invested in equity and debt securities, bank deposits, etc. The investment is conducted at the discretion of the Bureau or under the mandated management. However, in accordance with relevant regulations, the return generated by plan assets should not be below the interest rate for a 2-year b) Interest risk A decrease in the government bond interest rate will increase the present value of the defined benefit obligation; however, this will be partially offset by an increase in the return on the plan’s debt investments. c) Salary risk The present value of the defined benefit obligation is calculated by reference to the future salaries of plan participants. As such, an increase in the salary of the plan participants will increase the present value of the defined benefit obligation. 7) The management of ASE Korea is responsible for the administration of the fund and determination of the investment strategies according to related local regulations. ASE Korea is responsible for the shortfall between the fund and the defined benefit obligation. The plan assets are investment 8) The present value of the defined benefit obligation and the related current service cost and past service cost were measured using the Projected Unit Credit Method. Except the pension plans for executive managers, the key assumptions used for the actuarial valuations were as follow: December 31 2020 2021 Discount rates (%) 0.00-2.77 0.05-3.31 Expected rates of salary increase (%) 1.00-4.06 1.00-4.02 The sensitivity analysis below has been determined based on reasonably possible changes of the respective assumptions occurring at each balance sheet date, while holding all other assumptions constant. December 31 2020 2021 NT$ NT$ US$ (Note 4) Discount rate 0.5% higher $ (617,803 ) $ (548,265 ) $ (19,764 ) 0.5% lower $ 600,451 $ 593,980 $ 21,412 Expected rates of salary increase 0.5% higher $ 611,217 $ 538,689 $ 19,419 0.5% lower $ (565,555 ) $ (503,700 ) $ (18,158 ) The sensitivity analysis presented above may not be representative of the actual change in the defined benefit obligation as it is unlikely that the change in assumptions would occur in isolation of one another as some of the assumptions may be correlated. 9) Maturity analysis of undiscounted pension benefit December 31 2020 2021 NT$ NT$ US$ (Note 4) No later than 1 year $ 498,092 $ 561,812 $ 20,253 Later than 1 year but not later than 5 years 2,553,522 2,593,560 93,495 Later than 5 years 12,325,576 12,600,192 454,225 $ 15,377,190 $ 15,755,564 $ 567,973 The Group expected to make contributions of NT$513,781 thousand and NT$595,871 thousand (US$21,481 thousand) to the defined benefit plans in the next year starting from January 1, 2021 and 2022, respectively. As of December 31, 2020 and 2021, the average duration of the defined benefit obligation excluding those for executive managers of the Group both were 9 to 16 years .

Equity

Equity	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Equity	24. EQUITY a. Share capital Ordinary shares December 31 2020 2021 Numbers of shares authorized (in thousands) 5,500,000 5,500,000 Numbers of shares reserved (in thousands) Employee share options 400,000 400,000 Number of shares issued and fully paid (in thousands) 4,351,592 4,408,650 December 31 2020 2021 NT$ NT$ US$ (Note 4) Share capital authorized $ 55,000,000 $ 55,000,000 $ 1,982,696 Share capital reserved Employee share options $ 4,000,000 $ 4,000,000 $ 144,196 American Depositary Receipts The Company’s ADS represents 2 ordinary shares of the Company. As of December 31, 2020 and 2021, 107,964 thousand and 157,164 thousand ADSs were outstanding and represented 215,927 thousand and 314,328 thousand ordinary shares of the Company, respectively. b. Capital surplus December 31 2020 2021 NT$ NT$ US$ (Note 4) May be used to offset a deficit, distributed as cash dividends, or transferred to share capital (1) Issuance of ordinary shares $ 13,548,426 $ 16,049,286 $ 578,561 Merger by share exchange 117,693,658 117,693,658 4,242,742 Difference between consideration and the carrying amount of the subsidiaries’ net assets during actual disposal or acquisition 3,240,987 3,240,987 116,835 Exercised employee share options 1,617,254 2,362,951 85,182 Treasury share transactions 510,449 816,186 29,422 Expired share options (Note 28) 645,903 645,903 23,284 137,256,677 140,808,971 5,076,026 May be used to offset a deficit only Changes in percentage of ownership interest in subsidiaries (2) 1,451 1,451 52 Share of changes in capital surplus of associates 41,239 10,706 386 Dividends that the claim period has elapsed and unclaimed by shareholders 3,550 5,183 187 46,240 17,340 625 May not be used for any purpose Employee share options 1,894,952 1,442,132 51,988 Employee restricted stock awards — 1,193,782 43,034 Others (3) 569,681 230,943 8,326 2,464,633 2,866,857 103,348 $ 139,767,550 $ 143,693,168 $ 5,179,999 1) Such capital surplus may be used to offset a deficit; in addition, when the Company has no deficit, such capital surplus may be distributed as cash dividends or transferred to share capital (limited to a certain percentage of the Company’s capital surplus and once a year). 2) Such capital surplus arises from the effects of changes in ownership interests in subsidiaries resulting from equity transactions other than actual disposals or acquisitions, or from changes in capital surplus of subsidiaries accounted for using the equity method. 3) Such capital surplus represents the excess of the carrying amount of related accounts over the par value due to employee share options exercised and the Company has not completed registration formalities. c. Retained earnings and dividend policy The Articles of Incorporation of the Company (the “Articles”) provides that annual net income shall be distributed in the following order: 1) Replenishment of deficits; 2) 10.0% as legal reserve; 3) Special reserve appropriated or reversed in accordance with laws or regulations set forth by the authorities concerned; 4) If annual net income remains, a proposal for the distribution of such amount together with a part or all of the accumulated undistributed profits from two-thirds For the policies on the distribution of employees’ compensation and remuneration of directors, refer to employees’ compensation and remuneration of directors in Note 25(g). The Company is currently in the mature growth stage. To meet the capital needs for business development now and in the future and satisfy the shareholders’ demand for cash inflows, the Company shall use residual dividend policy to distribute dividends, of which the cash dividend is not lower than 30% of the total dividend distribution, with the remainder to be distributed in shares. A distribution plan is also to be made by the board of directors and passed for resolution in the shareholders’ meeting. Appropriation of earnings to legal reserve shall be made until the legal reserve equals the Company’s share capital. Legal reserve may be used to offset deficits. If the Company has no deficit and the legal reserve has exceeded 25% of the Company’s share capital, the excess may be transferred to capital or distributed in cash. Items referred to under Rule No. 1090150022 issued by the Financial Supervisory Commission R.O.C. and in the directive titled “Questions and Answers for Special Reserves Appropriated Following Adoption of IFRSs” should be appropriated to or reversed from a special reserve by the Company. The appropriation of earnings for 2019 and 2020 resolved in , Appropriation of Earnings Dividends Per Share For Year 2019 For Year 2020 For Year 2019 For Year 2020 NT$ NT$ NT$ NT$ (in dollars) (in dollars) Legal reserve $ 1,697,489 $ 2,398,814 Special reserve (reverse) 3,944,915 (1,278,670 ) Cash dividends 8,668,331 18,389,856 $ 2.0 $ 4.2 $ 14,310,735 $ 19,510,000 d. Others equity items 1) Exchange differences on translating foreign operations For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Balance at January 1 $ (5,888,574 ) $ (10,762,684 ) $ (11,641,939 ) $ (419,681 ) Recognized for the year Exchange differences a ri ng (4,788,135 ) (1,173,204 ) (3,203,730 ) (115,491 ) Share from associates and joint venture accounted for using the equity method (85,975 ) 101,038 21,307 768 Reclassification Disposal of associates and joint venture accounted for using the equity method — 29,971 — — Disposal of foreign operations — 162,940 (569,284 ) (20,522 ) Balance at December 31 $ (10,762,684 ) $ (11,641,939 ) $ (15,393,646 ) $ (554,926 ) 2) Unr e For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Balance at January 1 $ (1,015,107 ) $ (203,098 ) $ 2,027,902 $ 73,104 Unrealized gain (loss) recognized during the year Debt instruments (2,052 ) (2,136 ) 63,722 2,297 Equity instruments (283,472 ) (405,020 ) (8,671 ) (313 ) Share from associates and joint venture accounted for using the equity method 1,501,689 2,655,570 3,599,703 129,766 Realized gain (loss) recognized during the year Disposal of associates and joint venture accounted for using the equity method — 1,094 — — Cumulative unrealized loss of equity instruments transferred to retained earnings due to disposal — 16,383 33,258 1,199 Cumulative unrealized loss transferred to retained earnings due to disposal of equity instruments in relation to associates and joint venture accounted for using the equity method (404,156 ) (34,891 ) (1,525,553 ) (54,995 ) Balance at December 31 $ (203,098 ) $ 2,027,902 $ 4,190,361 $ 151,058 3) Gain (loss) on hedging instruments - For the Year Ended December 31 2020 2021 NT$ NT$ US$ (Note 4) Balance at January 1 $ — $ (429,265 ) $ (15,475 ) Recognized during the year Foreign currency risk – loans denominated in foreign currency (429,265 ) 551,098 19,867 Balance at December 31 $ (429,265 ) $ 121,833 $ 4,392 (Concluded) 4) Unearned employee compensation In August 2021, the shareholders’ meeting resolved to issue restricted stock awards for employees . R For the Year Ended NT$ US$ (Note 4) Balance at January 1 $ — $ — Issuance of employee restricted stock awards (1,343,782 ) (48,442 ) Share-based payment expenses 178,791 6,446 Balance at December 31 $ (1,164,991 ) $ (41,996 ) e. Treasury shares (in thousand shares) Purpose of Repurchase Shares Shares held by Total Balance at December 31, 2020 — 72,941 72,941 Balance at January 1, 2021 — 72,941 72,941 Addition 53,067 — 53,067 Balance at December 31, 2021 53,067 72,941 126,008 In order to maintain the Company’s credit and shareholders’ rights and interests, the in November 202 1 for cancellation . I continuous to execute th e repurchase. As of December 31, 2021, the Company early the of were bought back before December 31, 2021 at an average price of NT$104.2 (US$ 3.8) while the remaining thousand shares were bought back during January 2022 at an average price of NT$106.4 (US$3.8). In February 2022, the Company’s board of directors resolved that February 25, 2022 was the record date for capital reduction and completed the cancellation of those repurchased ordinary shares. The Company’s shares held by its subsidiaries at each balance sheet date were as follows: Shares Held by Carrying Carrying Fair Value Fair Value (in thousand NT$ US$ (Note 4) NT$ US$ (Note 4) December 31, 2020 ASE Test 44,100 $ 1,380,721 $ 3,585,349 J&R Holding 23,352 381,709 1,898,508 ASE Test, Inc. 5,489 196,677 446,287 72,941 $ 1,959,107 $ 5,930,144 December 31, 2021 ASE Test 44,100 $ 1,380,721 $ 49,774 $ 4,696,675 $ 169,311 J&R Holding 23,352 381,709 13,760 2,486,975 89,653 ASE Test, Inc. 5,489 196,677 7,090 584,620 21,075 72,941 $ 1,959,107 $ 70,624 $ 7,768,270 $ 280,039 Fair value (Level 1) of the Company’s shares held by subsidiaries is based on the closing price from an available published price quotation. Under the Securities and Exchange Act in the R.O.C., the Company shall neither pledge treasury shares nor exercise shareholders’ rights on these shares, such as the rights to dividends and voting. The subsidiaries holding the aforementioned treasury shares are bestowed shareholders’ rights except the rights to participate in any share issuance for cash and voting. f. Non-controlling For the Year Ended December 31 2019 2020 (retrospectively 2021 NT$ NT$ NT$ US$ (Note 4) Balance at January 1 (retrospectively adjusted) $ 17,639,487 $ 13,374,912 $ 15,622,009 $ 563,158 Share of profit for the year 1,207,974 1,681,320 2,099,830 75,697 Other comprehensive income (loss) for the year Exchange difference on translating foreign operations (414,010 ) 178,480 (321,551 ) (11,592 ) Unrealized gain (10,773 ) 1,321 50,679 1,827 Gain (loss) — (145,559 ) 187,502 6,759 Remeasurement on defined benefit plans (7,422 ) (9,075 ) 1,497 54 Share of from — — 7,902 285 Non-controlling 666,651 298 — — Acquisition of non-controlling (5,084,785 ) (116,738 ) — — Issuance of ordinary shares by subsidiaries (Note 29) 83,044 1,711,453 — — Subsidiaries’ buy back of their own outstanding ordinary shares (Note 31) (2,017,319 ) (2,299,533 ) (2,748,521 ) (99,081 ) Equity component of convertible bonds issued by subsidiaries — — 393,199 14,174 Non-controlling 1,672,310 1,591,904 314,398 11,334 Cash dividends d ist ri buted non-controlling (360,245 ) (346,774 ) (1,062,529 ) (38,303 ) Balance at December 31 $ 13,374,912 $ 15,622,009 $ 14,544,415 $ 524,312

Profit Before Income Tax

Profit Before Income Tax	12 Months Ended
	Dec. 31, 2021
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Profit Before Income Tax	25. PROFIT BEFORE INCOME TAX a. Other operating income and expenses, net For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Rental income $ 136,301 $ 153,682 $ 175,373 $ 6,322 Gain (loss) on disposal of property, plant and equipment (164,467 ) 460,868 71,770 2,587 Royalty income — — 135,400 4,881 Impairment loss (Note 15) (201,006 ) (992,273 ) (126,766 ) (4,571 ) Others (39,383 ) 880,215 934,052 33,673 $ (268,555 ) $ 502,492 $ 1,189,829 $ 42,892 b. Other income For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Interest income Bank deposits $ 549,681 $ 520,783 $ 529,132 $ 19,074 Contracts with customers — — 13,197 476 Government subsidies 624,351 803,049 767,918 27,683 Dividends income 185,061 150,715 289,852 10,449 $ 1,359,093 $ 1,474,547 $ 1,600,099 $ 57,682 c. Other gains and losses For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Remeasurement gain on investments accounted for using the equity method due to step acquisition $ 319,712 $ — $ — $ — Net gain on financial assets mandatorily at FVTPL 3,631,763 3,211,125 1,199,065 43,225 Net loss arising on financial instruments held for trading (1,984,941 ) (3,282,973 ) (2,689,070 ) (96,938 ) Gain on disposal of subsidiaries (Note 30) — 802,753 17,340,418 625,105 Foreign exchange gain, net 1,125,681 1,005,374 1,395,054 50,290 Gain recognized in bargain purchase transaction (Note 29) — — 33,114 1,194 Gain (loss) on disposal of investments accounted for using the equity method — 91,297 (67,482 ) (2,433 ) Impairment loss on financial assets (400,201 ) — — — Others (8,025 ) — — — $ 2,683,989 $ 1,827,576 $ 17,211,099 $ 620,443 d. Finance costs For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Interest on lease liabilities $ 88,742 $ 88,026 $ 105,159 $ 3,791 Interest on borrowings and bonds payable 4,211,541 3,498,999 2,790,368 100,590 Total interest expense for financial liabilities measured at amortized cost 4,300,283 3,587,025 2,895,527 104,381 Less: Amounts included in the cost of qualifying assets Inventories related to real estate business (35,713 ) (95,589 ) (71,011 ) (2,560 ) Property, plant and equipment (77,715 ) (54,208 ) (25,581 ) (922 ) 4,186,855 3,437,228 2,798,935 100,899 Other finance costs 16,540 22,283 32,372 1,167 $ 4,203,395 $ 3,459,511 $ 2,831,307 $ 102,066 Information relating to the capitalized borrowing costs was as follows: For the Year Ended December 31 2019 2020 2021 Annual interest capitalization rates Inventories related to real estate business (%) 4.35-4.85 4.20-4.75 4.20-4.35 Property, plant and equipment (%) 0.96-4.03 0.49-3.47 0.48-1.08 e. Depreciation and amortization For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Property, plant and equipment $ 45,240,667 $ 46,016,548 $ 48,604,160 $ 1,752,133 Right-of-use 1,055,458 946,880 1,114,950 40,193 Investment properties 594,110 562,260 751,047 27,074 Other intangible assets 3,576,606 3,733,377 4,054,120 146,147 Total $ 50,466,841 $ 51,259,065 $ 54,524,277 $ 1,965,547 Summary of depreciation by function Operating costs $ 43,749,333 $ 44,017,839 $ 46,880,267 $ 1,689,988 Operating expenses 3,140,902 3,507,849 3,589,890 129,412 $ 46,890,235 $ 47,525,688 $ 50,470,157 $ 1,819,400 Summary of amortization by function Operating costs $ 2,092,074 $ 2,231,060 $ 2,443,870 $ 88,099 Operating expenses 1,484,532 1,502,317 1,610,250 58,048 $ 3,576,606 $ 3,733,377 $ 4,054,120 $ 146,147 Operating expenses directly related to investment properties For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Direct operating expenses of investment properties that generated rental income $ 1,232,826 $ 1,121,854 $ 1,422,463 $ 51,278 f. Employee benefits expense For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Post-employment benefits Defined contribution plans $ 3,148,209 $ 2,979,167 $ 3,489,642 $ 125,798 Defined benefit plans 277,041 217,186 214,599 7,736 3,425,250 3,196,353 3,704,241 133,534 Equity-settled share-based payments 871,699 955,575 699,211 25,206 Other employee benefits 70,279,752 76,648,412 90,412,118 3,259,269 $ 74,576,701 $ 80,800,340 $ 94,815,570 $ 3,418,009 Summary of employee benefits expense by function Operating costs $ 49,173,778 $ 52,526,164 $ 61,555,563 $ 2,219,018 Operating expenses 25,402,923 28,274,176 33,260,007 1,198,991 $ 74,576,701 $ 80,800,340 $ 94,815,570 $ 3,418,009 g. Employees’ compensation and the remuneration to directors The Articles stipulates to distribute employees’ compensation and remuneration to directors at the rates of 0.01%-1.00% For the Year Ended December 31 2020 2021 Accrual Accrual Accrual Accrual Amount NT$ NT$ US$ (Note 4) Employees’ compensation 0.20 $ 54,909 0.19 $ 121,935 $ 4,396 Remuneration to directors 0.40 109,818 0.30 195,095 7,033 If there is a change in the proposed amounts after the consolidated financial statement authorized for issue, the differences are recorded as a change in accounting estimate and will be adjusted in the following year. In March 2020 and 2021, the board of directors resolved the appropriations of employees’ compensation and remuneration to directors in cash for 2019 and 2020, respectively. The differences between the resolved amounts and the accrued amounts reflected in the annual consolidated financial statements for the years ended December 31, 2019 and 2020 were deemed changes in estimates. The differences were NT$3 thousand and NT$818 thousand (US$29 thousand) and were adjusted in net profit for each of the year ended December 31, 2020 and 2021, respectively. For Year 2019 For Year 2020 Employees’ Remuneration Employees’ Remuneration NT$ NT$ NT$ NT$ Resolved by the board of directors $ 34,400 $ 68,800 $ 54,909 $ 109,000 Recognized in the consolidated financial statements $ 34,400 $ 68,803 $ 54,909 $ 109,818 Information on the employees’ compensation and the remuneration to directors resolved by the board of directors is available at the Market Observation Post System website of the Taiwan Stock Exchange (the “TWSE”).

Income Tax

Income Tax	12 Months Ended
	Dec. 31, 2021
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Income Tax	26. INCOME TAX The Company and its subsidiaries, ASE, SPIL and USIINC, have filed a consolidated tax return for corporate income tax and for unappropriated earnings. a. Income tax recognized in profit or loss The major components of income tax were as follows: For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Current income tax In respect of the current year $ 5,002,954 $ 6,807,882 $ 14,533,570 $ 523,921 Income tax on unappropriated earnings 19,115 680,649 3,684,138 132,810 Changes in estimate for prior years (352,579 ) (472,512 ) (129,152 ) (4,656 ) 4,669,490 7,016,019 18,088,556 652,075 Deferred income tax In respect of the current year 563,512 212,338 (95,906 ) (3,457 ) Changes in tax rates 54,072 — 18,337 660 Changes in estimate for prior years (213,758 ) (103,021 ) 16,625 600 Effect of foreign currency exchange differences (62,070 ) (8,438 ) (83,840 ) (3,022 ) 341,756 100,879 (144,784 ) (5,219 ) Income tax expense recognized in profit or loss $ 5,011,246 $ 7,116,898 $ 17,943,772 $ 646,856 A reconciliation of income tax expense calculated at the statutory rates and income tax expense recognized in profit or loss was as follows: For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Profit before income tax $ 23,279,811 $ 35,768,798 $ 80,193,769 $ 2,890,906 Income tax expense calculated at the statutory rates $ 11,802,811 $ 16,907,904 $ 33,697,736 $ 1,214,771 Nontaxable expense in determining taxable income 459,133 316,619 357,936 12,903 Tax-exempt (495,883 ) (387,212 ) (14,578,355 ) (525,536 ) Additional income tax on unappropriated earnings 19,115 680,649 3,684,138 132,810 Income tax credits (898,198 ) (1,191,387 ) (1,654,821 ) (59,655 ) The origination and reversal of temporary differences (3,594,774 ) (6,033,652 ) 78,544 2,831 Income tax adjustments on prior years (352,579 ) (472,512 ) (112,527 ) (4,056 ) Unrecognized deferred tax liability for temporary differences associated with investments (1,993,561 ) (2,616,917 ) (6,135,120 ) (221,165 ) Unrecognized loss carryforwards — — 288,025 10,383 Realized investment loss on merger of subsidiary — (138,890 ) — — Withholding tax 65,182 52,296 87,175 3,143 Land value increment tax — — 117,341 4,230 Capital gains tax — — 2,113,700 76,197 Income tax expense recognized in profit or loss $ 5,011,246 $ 7,116,898 $ 17,943,772 $ 646,856 In July 2019, the President of the R.O.C. announced the amendments to the Statute for Industrial Innovation, which stipulate that the amounts of unappropriated earnings in 2018 and thereafter that are reinvested in the construction or purchase of certain assets or technologies are allowed as deduction when computing the income tax on unappropriated earnings. When calculating the tax on unappropriated earnings, the Group only deducts the amount of the unappropriated earnings that has been reinvested in capital expenditure. In addition, in accordance with Rule No.10904558730 issued by the Ministry of Finance of Taiwan, the Group has deducted the amount of dividends distributed in 2020 attributable to the increase in the retained earnings as of January 1, 2018 as a result of initial adoption of IFRS 9 and IFRS 15 when calculating the tax on unappropriated earnings for 2018. b. Income tax recognized directly in equity For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Deferred income tax Related to employee share options $ 1,404 $ (1,159 ) $ (9 ) $ (0 ) c. Income tax recognized in other comprehensive income For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Deferred income tax Related to remeasurement of defined benefit plans $ 74,308 $ 114,559 $ (19,319 ) $ (696 ) Unrealized loss on equity instruments at fair value through other comprehensive income (78,124 ) (237,460 ) (160,084 ) (5,771 ) Income tax recognized in other comprehensive income $ (3,816 ) $ (122,901 ) $ (179,403 ) $ (6,467 ) d. Current tax assets and liabilities December 31 2020 2021 NT$ NT$ US$ (Note 4) Current tax assets Tax refund receivable $ 303,265 $ 207,272 $ 7,472 Prepaid income tax 399,555 334,908 12,073 $ 702,820 $ 542,180 $ 19,545 Current tax liabilities Income tax payable $ 6,514,502 $ 16,362,350 $ 589,847 e. Deferred tax assets and liabilities The Group offset certain deferred tax assets and deferred tax liabilities which met the offset criteria. The movements of deferred tax assets and deferred tax liabilities were as follows: For the year ended December 31, 2019 Balance at Recognized in Recognized in Other Recognized in Equity Exchange Acquisitions Balance at NT$ NT$ NT$ NT$ NT$ NT$ NT$ Deferred tax assets Temporary differences Property, plant and equipment $ 689,790 $ (119,972 ) $ — $ — $ (25,023 ) $ 49 $ 544,844 Defined benefit obligation 1,064,824 (57,746 ) 74,308 — (2,803 ) — 1,078,583 FVTPL financial instruments 211,556 47,991 — — (40 ) — 259,507 Others 1,838,746 (84,377 ) — 1,160 (24,906 ) 14,326 1,744,949 3,804,916 (214,104 ) 74,308 1,160 (52,772 ) 14,375 3,627,883 Loss carry-forward 672,275 (166,128 ) — — (12,203 ) 48,837 542,781 Investment credits 631,166 (86,722 ) — — (7,404 ) — 537,040 $ 5,108,357 $ (466,954 ) $ 74,308 $ 1,160 $ (72,379 ) $ 63,212 $ 4,707,704 Deferred tax liabilities Temporary differences Property, plant and equipment $ 5,236,104 $ (39,379 ) $ — $ — $ (7,074 ) $ 16,966 $ 5,206,617 FVTPL financial instruments 4,535 4,706 — — (49 ) — 9,192 Others 566,074 (90,524 ) 78,124 (244 ) (3,144 ) 6,142 556,428 $ 5,806,713 $ (125,197 ) $ 78,124 $ (244 ) $ (10,267 ) $ 23,108 $ 5,772,237 For the year ended December 31, 2020 (retrospectively adjusted) Balance at Recognized in Recognized in Other Recognized in Equity Exchange Acquisitions Disposal of Balance at NT$ NT$ NT$ NT$ NT$ NT$ NT$ NT$ Deferred tax assets Temporary differences Property, plant and equipment $ 544,844 $ 4,632 $ — $ — $ 12,435 $ 81,773 $ (13,982 ) $ 629,702 Defined benefit obligation 1,078,583 (36,633 ) 114,559 — 1,005 212,941 — 1,370,455 FVTPL financial instruments 259,507 (138,045 ) — — (7 ) 2,085 (11,281 ) 112,259 Others 1,744,949 679,197 — (999 ) (45,169 ) 150,291 (120,359 ) 2,407,910 3,627,883 509,151 114,559 (999 ) (31,736 ) 447,090 (145,622 ) 4,520,326 Loss carry-forward 542,781 (44,651 ) — — (915 ) 183,045 (152,594 ) 527,666 Investment credits 537,040 (86,100 ) — — (21,559 ) — — 429,381 $ 4,707,704 $ 378,400 $ 114,559 $ (999 ) $ (54,210 ) $ 630,135 $ (298,216 ) $ 5,477,373 Deferred tax liabilities Temporary differences Property, plant and equipment $ 5,206,617 $ 427,465 $ — $ — $ (29,248 ) $ 375,553 $ — $ 5,980,387 FVTPL financial instruments 9,192 (2,942 ) — — 67 — — 6,317 Others 556,428 54,755 237,460 160 (1,060 ) 287,375 (795 ) 1,134,323 $ 5,772,237 $ 479,278 $ 237,460 $ 160 $ (30,241 ) $ 662,928 $ (795 ) $ 7,121,027 For the year ended December 31, 2021 Balance at (retrospectively Recognized in Recognized in Other Recognized in Equity Exchange Disposal of Balance at NT$ NT$ NT$ NT$ NT$ NT$ NT$ Deferred tax assets Temporary differences Property, plant and equipment $ 629,702 $ (186,443 ) $ — $ — $ (7,178 ) $ (345,104 ) $ 90,977 Defined benefit obligation 1,370,455 (115,707 ) (19,319 ) — (47,276 ) — 1,188,153 FVTPL financial instruments 112,259 77,593 — — (502 ) — 189,350 Others 2,407,910 679,492 — (7 ) 52,399 (269,080 ) 2,870,714 4,520,326 454,935 (19,319 ) (7 ) (2,557 ) (614,184 ) 4,339,194 Loss carry-forward 527,666 187,981 — — (31,077 ) (45,788 ) 638,782 Investment credits 429,381 (15,549 ) — — (22,798 ) — 391,034 $ 5,477,373 $ 627,367 $ (19,319 ) $ (7 ) $ (56,432 ) $ (659,972 ) $ 5,369,010 Deferred tax liabilities Temporary differences Property, plant and equipment $ 5,980,387 $ 165,628 $ — $ — $ (42,437 ) $ (186,834 ) $ 5,916,744 FVTPL financial instruments 6,317 6,274 — — (11 ) — 12,580 Others 1,134,323 310,681 160,084 2 69,848 (14,065 ) 1,660,873 $ 7,121,027 $ 482,583 $ 160,084 $ 2 $ 27,400 $ (200,899 ) $ 7,590,197 Balance at (retrospectively adjusted) Recognized in Recognized in Other Recognized in Equity Exchange Disposal of Balance at US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Deferred tax assets Temporary differences Property, plant and equipment $ 22,700 $ (6,721 ) $ — $ — $ (259 ) $ (12,441 ) $ 3,279 Defined benefit obligation 49,404 (4,171 ) (696 ) — (1,704 ) — 42,833 FVTPL financial instruments 4,047 2,797 — — (18 ) — 6,826 Others 86,803 24,495 — (0 ) 1,889 (9,700 ) 103,487 162,954 16,400 (696 ) (0 ) (92 ) (22,141 ) 156,425 Loss carry-forward 19,022 6,777 — — (1,121 ) (1,651 ) 23,027 Investment credits 15,479 (561 ) — — (822 ) — 14,096 $ 197,455 $ 22,616 $ (696 ) $ (0 ) $ (2,035 ) $ (23,792 ) $ 193,548 Deferred tax liabilities Temporary differences Property, plant and equipment $ 215,587 $ 5,971 $ — $ — $ (1,530 ) $ (6,735 ) $ 213,293 FVTPL financial instruments 228 226 — — (1 ) — 453 Others 40,891 11,200 5,771 0 2,518 (507 ) 59,873 $ 256,706 $ 17,397 $ 5,771 $ 0 $ 987 $ (7,242 ) $ 273,619 f. Items for which no deferred tax assets have been recognized for loss carry-forward, investment credits and deductible temporary differences December 31 2020 2021 NT$ NT$ US$ (Note 4) Loss carry-forward $ 1,497,056 $ 1,340,849 $ 48,336 Investment credits 49,611 44,244 1,595 Deductible temporary differences 377,242 241,249 8,697 $ 1,923,909 $ 1,626,342 $ 58,628 The unrecognized loss carry-forward will expire through 2030. g. Information about unused loss carry-forward, unused investment credits, tax-exemption As of December 31, 2021, the unused loss carry-forward comprised: Expiry Year NT$ US$ (Note 4) 2022 $ 243,136 $ 8,765 2023 192,254 6,930 2024 171,664 6,188 2025 185,524 6,688 2026 and thereafter 1,187,051 42,792 $ 1,979,629 $ 71,363 As of December 31, 2021, unused investment credits comprised: Tax Credit Source Remaining Creditable Amount Expiry Year NT$ US$ (Note 4) Purchase of machinery and equipment $ 370,360 $ 13,351 2026 Others 64,918 2,340 2026 and thereafter $ 435,278 $ 15,691 As of December 31, 2021, profits attributable to the following expansion project is exempted from income tax for a 5-year Tax-exemption Period Construction and expansion of ASE Test Inc. in 2009 2018.01 2022.12 Some China subsidiaries qualified as high technology enterprises were entitled to a reduced income tax rate of 15% and were eligible to deduct certain times of research and development expenses from their taxable income. h. Unrecognized deferred tax liabilities associated with investments As of December 31, 2020 and 2021, the taxable temporary differences associated with the investments in subsidiaries for which no deferred tax liabilities have been recognized were NT$33,474,725 thousand and NT$39,480,927 thousand (US$1,423,249 thousand), respectively. i. Income tax assessments The tax authorities have examined income tax returns of the Company and its R.O.C. subsidiaries through 2018 and 2019.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Earnings Per Share	27. EARNINGS PER SHARE The earnings and weighted average number of ordinary shares outstanding in the computation of earnings per share were as follows: Net profit for the year For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Profit for the year attributable to owners of the Company $ 17,060,591 $ 26,970,580 $ 60,150,167 $ 2,168,353 Effect of potentially dilutive ordinary shares: Potential ordinary s of the subsid iary (385,865 ) (521,073 ) (1,056,778 ) (38,096 ) Earnings used in the computation of diluted earnings per share $ 16,674,726 $ 26,449,507 $ 59,093,389 $ 2,130,257 Weighted average number of ordinary shares outstanding For the Year Ended December 31 2019 2020 2021 Weighted average number of ordinary shares in the 4,251,964 4,265,732 4,305,348 Effect of potentially dilutive ordinary shares Employee share options 10,232 22,086 58,113 Employees’ compensation 570 815 1,264 Employee restricted stock awards — — 943 Weighted average number of ordinary shares in the 4,262,766 4,288,633 4,365,668 For the computation of earnings per ADS, the denominators were the half of the aforementioned weighted average outstanding shares (1 ADS represents 2 ordinary shares) while the numerators held constant. The Group is able to settle the employees’ compensation by cash or shares. The Group assumed that the entire amount of the compensation would be settled in shares and the resulting potential shares were included in the weighted average number of ordinary shares outstanding used in the computation of diluted earnings per share if the effect is dilutive. Such dilutive effect of the potential shares was included in the computation of diluted earnings per share until the board of directors approve the number of shares to be distributed to employees at their meeting in the

Share-based Payment Arrangement

Share-based Payment Arrangements	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Share-based Payment Arrangements	28. SHARE-BASED PAYMENT ARRANGEMENTS a. Employee share option plans of the Company In order to attract, retain and reward employees, the Company and its subsidiary, ASE, have their employee share option plans for the Group’s full-time employees. As disclosed in Note 1, the Company assumed ASE’s obligations of outstanding employee share option plans starting from April 30, 2018 and each share option represents the right to purchase 0.5 ordinary share of the Company when exercised. Under the terms of the plan, share options are granted at an exercise price equal to or not less than the closing price of the ordinary shares listed on the TWSE at the issue date. The right of those share options granted under the plan is valid for 10 years, non-transferable Information about the share option plans that the Company granted and assumed For the Year Ended December 31 2019 2020 2021 Weighted Weighted Weighted Average Average Average Number of Exercise Number of Exercise Number of Exercise Options Price Options Price Options Price (In Per Share (In Per Share (In Per Share Thousands) (NT$) Thousands) (NT$) Thousands) (NT$) Balance at January 1 183,814 $ 58.1 170,786 $ 57.0 144,767 $ 56.9 Options expired — — (1,006 ) 40.8 — — Options forfeited (4,214 ) 61.8 (3,949 ) 58.0 (5,907 ) 52.3 Options exercised (8,814 ) 48.4 (21,064 ) 49.2 (42,058 ) 61.4 Balance at December 31 170,786 57.0 144,767 56.9 96,802 53.3 Options exercisable, end of year 33,822 63.5 67,388 61.4 49,696 55.5 The weighted average share prices at exercise dates of share options for the years ended December 31, 2019, 2020 and 2021 were NT$69.3, NT$68.5 and NT$108.8 (US$3.9), respectively. Information about the outstanding share options that the Company granted and assumed at each balance sheet date was as follows: Range of (NT$) Weighted Contractual December 31, 2020 ASE 4 th $ 45.2 0.3 ASE 5 th 73.0 4.7 The Company 1 st 52.9 7.9 December 31, 2021 ASE 5 th 73.0 3.7 The Company 1 st 51.0 6.9 b. Employee restricted stock awards plan of the Company To attract and retain talents as well as in August 202 1 granted thousand ordinary shares on the record date of October 1, 2021. The par value and the exercise price was NT$10 (US$0.36) and NT$0 per share, respectively . The fair value at the grant day was NT$92.4 (US$ 3.33 per s hare. The vested shares are settled and issued on an annual basis during a three-year period starting from October 1, 2021. Up to one-thirds of the total shares granted will be vested only after the Company reaching specific performance targets before the end of each year-period. Except for inheritance, those shares shall not be sold, pledged, transferred, gifted, conditioned, or otherwise dispose of before vest, while the rights of attendance, propose, speak, vote and election at shareholders meeting and other rights, including but not limited to, stock dividend, cash dividend, distribution from legal reserve and capital surplus, share options at cash capital increase are identical with the Company’s ordinary shares issued and outstanding. All the shares under this plan should be deposited in a trust account before vest. After the grant date, the Company has the right to revoke and cancel those unvested shares. The dividends (including cash dividends, stock dividends, and the cash or the shares distributed from legal reserve or capital surplus) entitled to those unvested shares and interests derived therefrom shall be returned to the Company from the trust account at the same time. c. Employee share option plans of subsidiaries USIE The terms of the plans issued by USIE were the same with those option plans previously granted by ASE. Information about share options was as follows: For the Year Ended December 31 2019 2020 Weighted Weighted Number of Average Exercise Number of Average Exercise Options Price Options Price (In Per Share (In Per Share Thousands) (US$) Thousands) (US$) Balance at January 1 16,711 $ 2.1 8,349 $ 2.3 Options forfeited — — (7 ) 2.9 Options exercised (8,362 ) 2.0 (8,342 ) 2.3 Balance at December 31 8,349 2.3 — — Options exercisable, end of year 8,349 2.3 — — In 2019 and 2020, the Group’s shareholdings in USIE decreased because USIE’s share options were exercised. The transaction was accounted for as an equity transaction since the Group did not cease to have control over USIE and, as a result, capital surplus was decreased by NT$981,078 in , capital surplus 1,120,111 thousand and NT$ thousand, respectively, in 2020. In addition, all of USIE’s share options were fully exercised as of December 31, 2020. USISH Under the share option plan issued in 2015 (“2015 share options”), each unit represents the right to purchase one ordinary share of USISH when exercised. The options are valid for 10 years, non-transferable In November 2019, USISH adopted the first share option plan (“2019 share options”) and granted 17,167 thousand share options to its employees. Each unit represents the right to purchase one ordinary share of USISH when exercised. The options are valid for 3.0 years, 4.0 years and 5.0 years, respectively, and are exercisable at certain percentages within 12 months subsequent to the second, the third and the fourth anniversary of the grant date under the satisfaction of certain performance conditions within each respective vesting period. In the event that USISH increases share capital by capital surplus or by cash, or distributes share dividends or cash dividends, the exercisable share option units and the exercise price are accordingly adjusted. In September 2020, USISH adopted the second share option plan (“2020 share options”) and granted 1,140 thousand share options to its employees. The conditions of issued 2020 share options are the same as 2019 share options plan, except that the options are valid for 2.2 years, 3.2 years and 4.2 years, respectively, and with each respective vesting period of 1.2 years, 2.2 years and 3.2 years. Information about share options was as follows: For the Year Ended December 31 2019 2020 2021 Number of Exercise Number of Exercise Number of Exercise Options Price Options Price Options Price (In Per Share (In Per Share (In Per Share Thousands) (RMB) Thousands) (RMB) Thousands) (RMB) Balance at January 1 21,537 $ 15.5 35,077 $ 14.5 31,266 $ 14.6 Options granted 17,167 13.3 1,140 21.7 — — Options forfeited (463 ) 15.4 (636 ) 14.0 (952 ) 14.5 Options exercised (3,164 ) 15.5 (4,315 ) 15.5 (828 ) 13.8 Balance at December 31 35,077 14.5 31,266 14.6 29,486 14.2 Options exercisable, end of year 13,694 15.5 13,416 15.5 19,249 14.8 Fair value of options granted (RMB) $ 6.27-8.35 $ 7.03-8.93 $ — Information about USISH’s outstanding share options at each balance sheet date was as follows: Range of (RMB) Remaining Contractual December 31, 2020 2015 share options $ 15.5 4.9 2019 share options 13.3 3.9 2020 share options 21.7 3.9 December 31, 2021 2015 share options 15.5 3.9 2019 share options 12.7 2.9 2020 share options 21.2 2.9 d Employee restricted stock In November 2019, USISH adopted the first restricted stock stocks lock-up In September 2020, USISH adopted the second restricted stock stocks stocks sto cks stocks lock-up In September 2021, USISH adopted the third restricted stock stocks st oc s sto cks Information about restricted stocks For the Year Ended December 31 2019 2020 2021 Number of Exercise Number of Exercise Number of Exercise Options Price Options Price Options Price (In Per Share (In Per Share (In Per Share Thousands) (RMB) Thousands) (RMB) Thousands) (RMB) Balance at January 1 — $ — 6,156 $ 13.3 5,547 $ 12.2 Options granted 6,156 13.3 672 4.9 281 — Options exercised — — (1,281 ) 13.2 (1,780 ) 12.7 Options forfeited — — — — (483 ) 12.1 Balance at December 31 6,156 13.3 5,547 12.2 3,565 10.2 Options exercisable, end of year — — — — — — Fair value of options granted (RMB) $ 13.47 $ 18.55 $ 11.78 Information about USISH’s outstanding restricted st oc Range of (RMB) Remaining Contractual December 31, 2020 2019 restricted st ocks $ 13.2 3.3 2020 restricted stocks — 1.7 December 31, 2021 2019 restricted st ocks 12.7 2.3 2020 restricted stocks — 0.7 2021 restricted st oc — 1.7 The Group’s shareholdings in USISH decreased because the abovementioned share option plans and restricted stock e Fair value information For the fair values at the grant date of USISH’s 2019, 2020 and 2021 plans, the share options plans were measured by using the trinomial tree model, while the restricted stocks lock-up Share option plan 2019 Share 2020 Share Share price at the grant date RMB15.84 per share RMB21.55 per share Exercise price RMB13.34 per share RMB21.65 per share Expected volatility (%) 45.07-51.80 48.14-53.57 Expected lives (years) 3-5 2.2-4.2 Expected dividend yield — — Risk free interest rate (%) 2.80-2.97 2.80-2.99 Restricted stock 2019 Restricted S 2019 Restricted Stocks in 2020 2020 Restricted Stocks 2021 Restricted Stocks Share price at the grant date RMB16.30 per share RMB16.60 per share RMB24.30 per share RMB14.65 per share Exercise price RMB13.34 per share RMB13.34 per share (Note) (Note) Expected volatility (%) 47.77 57.21 56.97 47.15 Lock-up 1 1 1.3 1.3 Expected dividend yield — — — — Risk free interest rate (%) 2.70 1.55 2.63 2.34 Note: The restricted st ock Expected volatilities were based on the annualized volatilities of USISH’s historical share prices. For the years ended December 31, 2019, 2020 and 2021, employee benefits expense recognized on the share-based payment plans were NT$871,699 thousand, NT$955,575 thousand and NT$699,211 thousand (US$25,206 thousand), respectively.

Business Combinations

Business Combinations	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Business Combinations	29. BUSINESS COMBINATIONS a. Subsidiaries acquired Principal Activity Date of Proportion of Consideration Transferred NT$ US$ (Note 4) AMPI Engaged in the manufacturing of integrated circuit April 30, 2019 50.97 $ 250,000 ASEEE Engaged in the production of embedded substrate April 26, 2019 51.00 $ — USIPL Engaged in the design and manufacturing of electronic components and new electronic applications October 31, 2019 60.00 $ 313,057 FAFG Holding company and the group engaged in the design and manufacturing of electronic components December 1, 2020 100.00 $ 12,443,637 ITGEU Trading company October 21, 2021 100.00 $ 50,368 $ 1,816 SER Engaged in the design and manufacturing of electronic components November 2, 2021 100.00 $ 217,919 $ 7,856 b. Consideration Transferred AMPI ASEEE USIPL FAFG ITGEU SER NT$ NT$ NT$ NT$ NT$ US$ (Note 4) NT$ US$ (Note 4) Cash $ 250,000 $ — $ 313,057 $ 11,094,802 $ 50,368 $ 1,816 $ 217,919 $ 7,856 Equity instrument issued — — — 1,734,570 — — — — Contingent consideration arrangement — — — (385,735 ) — — — — Fair value of identifiable net assets acquired $ 250,000 $ — $ 313,057 $ 12,443,637 $ 50,368 $ 1,816 $ 217,919 $ 7,856 In April 2019, the Group’s subsidiary, ASE Test, Inc., subscribed for 100,000 thousand ordinary shares of AMPI from its private placement with NT$250,000 thousand in cash. The percentage of the Group’s ownership in AMPI then increased to 50.97% and, therefore, the Group obtained control over AMPI. The investment in ordinary shares of AMPI originally accounted for using the equity method was remeasured to the fair value at the acquisition date and the Group recognized remeasurement gain of NT$243,057 thousand under the line item of other gains and losses. In April 2019, ASE entered into a memorandum of understanding with TDK Corporation (“TDK”) in relation to ASEEE that was incorporated by a joint venture agreement entered into by the Group and TDK. In addition to a reduction of one legal representative director of TDK, which resulted in that the Group obtained control over ASEEE starting from April 2019 and the investments in ASEEE originally accounted for using the equity method was remeasured to its fair value at the acquisition date with a remeasurement gain of NT$76,655 thousand under the line item of other gains and losses (Note 25), the memorandum of understanding set out that, after ASEEE offset its accumulated deficits against its capital in an amount of NT$1,147,595 thousand, ASE subscribed all of 150,000 thousand ordinary shares newly issued by ASEEE through its capital increase by cash in an amount of NT$1,500,000 thousand in May 2019 and then repurchased all of ASEEE’s ordinary shares held by TDK in an amount of US$6,000 thousand in July 2019. As a result, the Group eventually held 100% of ownership in ASEEE (Note 31). Furthermore, ASE merged ASEEE in February 2020. In October 2019, the Group’s subsidiary, Universal Global Electronics Co., Ltd., acquired 60% shareholdings of USIPL with a total consideration based on independent professional appraisal reports. In December 2020, the Group’s subsidiary, USIFR, paid NT$10,800,558 thousand (equivalent to US$368,753 thousand) in cash and the Group’s subsidiary, USISH, issued its 25,940 thousand new ordinary shares, respectively, to acquire 100% shareholdings of FAFG. In addition, according to the share purchase agreement, USIFR is obliged to pay an earn-out on the valuation report of fair In November 2021, the Group’s subsidiary, ASTEELFLASH FRANCE, acquired 100% shareholdings of SER and o btain ed . 202 1 the c. Assets acquired and liabilities assumed at the date of acquisition AMPI ASEEE USIPL FAFG ITGEU SER NT$ NT$ NT$ NT$ NT$ US$ (Note 4) NT$ US$ (Note 4) Assets Cash and cash equivalents $ 349,496 $ 23,197 $ 108,718 $ 2,349,164 $ 68,719 $ 2,477 $ 18,850 $ 680 Trade and other receivables 371,144 5,732 58,713 4,434,296 41,832 1,508 40,671 1,466 Inventories 403,887 11,033 229 4,836,819 — — 375,912 13,551 Property, plant and equipment 683,207 1,361,572 525,048 2,882,720 94 3 37,672 1,357 Intangible assets 128,900 290,757 11,704 1,541,155 32 1 368 14 Others 237,766 317,888 99,112 1,919,118 2,828 102 186,377 6,719 Liabilities Trade and other payables (224,295 ) (133,278 ) (217,887 ) (4,575,720 ) (29,165 ) (1,051 ) (214,883 ) (7,746 ) Borrowings and bonds payables (951,519 ) (1,371,395 ) (190,737 ) (356,417 ) — — — — Others (148,723 ) (290,273 ) (63,708 ) (3,155,051 ) (858 ) (31 ) (227,048 ) (8,185 ) Fair value of identifiable net assets acquired $ 849,863 $ 215,233 $ 331,192 $ 9,876,084 $ 83,482 $ 3,009 $ 217,919 $ 7,856 A call option on the remaining 40% non-controlling d. Non-controlling Non-controlling interests of AMPI and ASEEE were measured at their proportionate share of their fair value of AMPI’s and ASEEE’s identifiable net assets, respectively. Non-controlling interests of USIPL were measured at fair value at the acquisition date by using market approach incorporating transaction prices of comparable companies and the discount rate for lack of control. The significant unobservable inputs is the discount rate for lack of control of 31%. Non-controlling e. Goodwill recognized on acquisitions or gain recognized in bargain purchase transaction AMPI ASEEE USIPL FAFG ITGEU SER NT$ NT$ NT$ NT$ NT$ US$ (Note 4) NT$ US$ (Note 4) Consideration transferred $ 250,000 $ — $ 313,057 $ 12,443,637 $ 50,368 $ 1,816 $ 217,919 $ 7,856 Add: Fair value of 315,925 117,609 — — — — — — Add: Non-controlling 416,716 105,464 142,494 289 — — — — Less: Fair value of identifiable net assets acquired (849,863 ) (215,233 ) (331,192 ) (9,876,084 ) (83,482 ) (3,009 ) (217,919 ) (7,856 ) Goodwill recognized on acquisition (gain recognized in bargain purchase transaction) $ 132,778 $ 7,840 $ 124,359 $ 2,567,842 $ (33,114 ) $ (1,193 ) $ — $ — The goodwill from acquisitions mainly represents the control premium. In addition, the consideration paid for acquisitions effectively included amounts attributed to the benefits of expected synergies, such as revenue growth and future market expansions. These benefits are not recognized separately from goodwill because they do not meet the recognition criteria for identifiable intangible assets. The goodwill recognized on acquisitions is not expected to be deductible for tax purpose. f. Net cash outflow (inflow) on acquisition of subsidiaries AMPI ASEEE USIPL FAFG ITGEU SER NT$ NT$ NT$ NT$ NT$ US$ (Note 4) NT$ US$ (Note 4) Consideration transferred $ 250,000 $ — $ 313,057 $ 11,094,802 $ 50,368 $ 1,816 $ 217,919 $ 7,856 Less: Cash and cash equivalent acquired (349,496 ) (23,197 ) (108,718 ) (2,349,164 ) (68,719 ) (2,477 ) (18,850 ) (680 ) Net cash outflow (inflow) on acquisition of subsidiaries $ (99,496 ) $ (23,197 ) $ 204,339 $ 8,745,638 $ (18,351 ) $ (661 ) $ 199,069 $ 7,176 g. Impact of acquisitions on the results of the Group The results of operations since the acquisition date were included in the consolidated statements of comprehensive income and were as follows: AMPI (for the period ASEEE (for the period USIPL (for the period FAFG (for the period ITGEU (for the period October 21, 2021 SER (for the November 2, 2021 through NT$ NT$ NT$ NT$ NT$ US$ (Note 4) NT$ US$ (Note 4) Operating revenue $ 704,243 $ (1,159 ) $ 39,080 $ 2,043,440 $ 75,221 $ 2,712 $ 225,017 $ 8,112 Net profit (loss) $ (217,163 ) $ (469,598 ) $ (11,995 ) $ 91,179 $ (4,593 ) $ (166 ) $ (508 ) $ (18 ) Had the abovementioned pro-forma In determining the pro-forma pre-acquisition h. As of December 31, 2021, the Group has completed the identification of the difference between the cost of the investment and the Group’s share of FAFG’s net fair value of identifiable assets and liabilities, and has retrospectively adjusted the comparative consolidated financial statements as of and December 31, 2020 After Before NT$ NT$ Consolidated balance sheet Inventories $ 48,590,434 $ 48,516,459 Financial assets at fair value through profit or loss – non-current $ 2,180,978 $ 1,793,188 Property, plant and equipment $ 234,365,397 $ 233,207,324 Right-of-use $ 8,741,807 $ 8,620,612 Goodwill $ 52,709,053 $ 54,777,439 Other intangible assets $ 27,711,771 $ 26,808,668 Deferred tax liabilities $ 7,121,027 $ 6,551,233 Non-controlling $ 15,622,009 $ 15,616,053

Disposal of Subsidiaries

Disposal of Subsidiaries	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Disposal of Subsidiaries	30. DISPOSAL OF SUBSIDIARIES The board of directors of the Group’s subsidiary, SPIL (Cayman) Holding Limited, resolved in September 2020 to dispose its 100% shareholdings in Siliconware Electronics (Fujian) Co., Limited (“SF”) to Shenzhen Hiwin System Limited with a consideration of RMB966,000 thousand. The disposal was completed in October 2020 and the control over SF was transferred The board of directors of the Company resolved in December 2021 to dispose its 100% shareholdings in GAPT Holding Limited (including its subsidiaries) and ASEKS (collectively, “GAPT Holding and ASEKS”). The disposal was completed in December 2021 and the control over GAPT Holding and ASEKS was transferred to the acquirer. a. Analysis of assets and liabilities on the date control was lost 2020 2021 SF GAPT Holding and ASEKS NT$ NT$ US$ (Note 4) Current Assets Cash and cash equivalent $ 200,347 $ 2,625,715 $ 94,655 Trade and other 318,425 4,505,531 162,420 Inventories 239,865 2,284,880 82,368 Other current assets 111,913 1,215,992 43,835 Non-Current Property, plant and equipment 7,546,413 16,693,129 601,770 Right-of-use 812,861 181,855 6,556 Investment property — 787,250 28,379 Goodwill — 310,711 11,201 Deferred tax assets 298,217 659,972 23,792 Other non-current assets 43,482 308,500 11,122 Current Liabilities Short-term borrowings — (2,443,005 ) (88,068 ) Trade and other payables (1,739,330 ) (5,949,592 ) (214,477 ) Current portion of long-term borrowings (1,746,000 ) — — Other current liabilities (24,564 ) (647,027 ) (23,325 ) Non-Current Long-term borrowings (2,947,682 ) — — Deferred tax liabilities (796 ) (200,899 ) (7,242 ) Lease liabilities – non-current — (8,150 ) (294 ) Other non-current liabilities — (156,863 ) (5,655 ) Net assets disposed of $ 3,113,151 $ 20,167,999 $ 727,037 b. Gain on disposal of subsidiaries 2020 2021 SF GAPT Holding and ASEKS NT$ NT$ US$ (Note 4) Total consideration (paid in cash) $ 4,078,844 $ 36,939,133 $ 1,331,620 Net assets disposed of (3,113,151 ) (20,167,999 ) (727,037 ) Reclassification of accumulated exchange difference from equity to profit or loss due to the loss of control (162,940 ) 569,284 20,522 Gain on dis posals $ 802,753 $ 17,340,418 $ 625,105 c. Net cash inflow on disposals of subsidiaries 2020 2021 SF GAPT Holding and ASEKS NT$ NT$ US$ (Note 4) Consideration received in cash and cash equivalents $ 4,078,844 $ 36,939,133 $ 1,331,620 Less: Cash and cash equivalent balances disposed of (200,347 ) (2,625,715 ) (94,655 ) Other receivables (Note) (the outstanding receivables of consideration, net of relevant expenditure) (161,458 ) (10,533,600 ) (379,726 ) $ 3,717,039 $ 23,779,818 $ 857,239 Note: The outstanding receivables for the disposal of SF had

Equity Transaction with Non-con

Equity Transaction with Non-controlling Interests	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Equity Transaction with Non-controlling Interests	31. EQUITY TRANSACTION WITH NON-CONTROLLING a. USISH USISH repurchased its own 13,037 thousand outstanding ordinary shares during year ended December 31, 2019 and, as a resu l In September 2021, USISH repurchased its own 16,042 thousand outstanding ordinary shares at prices between RMB13.86 to RMB14.95 per share w b. USIPL In May 2020, the board of directors of Universal Global Electronics Co., Ltd. resolved to acquire 40% shareholdings of USIPL from Chung Hong Electronics (Suzhou) Co., Ltd. at RMB24,500 thousand. The aforementioned transaction resulted the Group’s shareholdings in USIPL to increase from 60% to 100%, and such transactions were accounted for as an equity transaction since the Group did not cease to have control over USIPL. The Group recognized a decrease in capital surplus by NT$13,502 thousand in the second quarter of 2020. c. USIE In July 2019, the shareholders’ meeting of USIE resolved to repurchase its own outstanding 7,378 thousand ordinary shares at US$14.30 per share, and, as a result, the Group’s shareholdings in USIE increased from 95.42% to 98.72%. The transaction was accounted for as an equity transaction since the transaction did not change the Group’s control over USIE and the Group capital surplus decreased by NT$1,625,448 thousand in 2019. In July 2019, the board of directors of USIE resolved July 23, 2019 was the record date for capital reduction and then the repurchased ordinary shares were subsequently cancelled. In September 2020, the shareholders’ meeting of USIE resolved to repurchase its own outstanding 10,308 thousand ordinary shares at US$19.47 per share, and as a result, the Group’s shareholdings of USIE increased from 95.00% to 99.62%. The transaction was accounted for as an equity transaction since the transaction did not change the Group’s control over USIE and capital surplus and retained earnings were decreased by NT$780,533 thousand and NT$2,760,175 thousand, respectively, in the third quarter of 2020. In September 2020, the board of directors of USIE resolved September 15, 2020 was the record date for capital reduction and then the repurchased ordinary shares were subsequently cancelled. In December 2021, the shareholders’ meeting of USIE resolved to repurchase its own outstanding 9,137 thousand ordinary shares at US$17.20 per share w hi ch made that d. ASEN and SZ In July 2019, ASE’s board of directors resolved to acquire 30% shareholdings of ASEN from Beijing Unis Capital Management Co., Ltd. at US$97,748 thousand by its subsidiary, J&R Holding. In addition, in July 2019, SPIL’s board of directors also resolved to acquire 30% shareholdings of SZ from Tibet Zixi Electronic Technology Co., Ltd. at US$162,870 thousand by its subsidiary, SPIL (Cayman) Holding Limited. The aforementioned transactions will result the Group’s shareholdings of ASEN and SZ both to increase from 70% to 100% and, therefore, both transactions will be accounted for as an equity transaction since the Group will not cease to have control over the subsidiaries. The Group recognized a decrease in capital surplus by NT$2,650,950 thousand in 2019. e. Others In July 2018, UGTW’s board of directors approved to acquire the outstanding ordinary shares of USI at NT$18 per ordinary shares. In 2019, UGTW completed the acquisition and recognized an increase in capital surplus by NT$142 thousand. As disclosed in Note 29, ASE purchased ASEEE’s ordinary shares through its capital increase in May 2019 and then repurchased all of ASEEE’s ordinary shares held by TDK in July 2019. As a result, the Group eventually held 100% of ownership in ASEEE and capital surplus was decreased by NT$128,805 thousand.

Cash Flows Information

Cash Flows Information	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Cash Flows Information	32. CASH FLOW INFORMATION a. Non-cash In addition to other notes, the Group entered into the following investing activities which include both cash and non-cash For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Payments for property, plant and equipment Purchase of property, plant and equipment $ 63,073,887 $ 59,024,201 $ 74,417,541 $ 2,682,681 Increase in other non-current 68,560 78,291 1,184,927 42,715 Decrease (increase) in other payables (6,254,579 ) 3,029,162 (4,671,228 ) (168,394 ) Capitalized borrowing costs (77,715 ) (54,208 ) (25,581 ) (922 ) $ 56,810,153 $ 62,077,446 $ 70,905,659 $ 2,556,080 Proceeds from disposal of property, plant and equipment Consideration from disposal of property, plant and equipment $ 441,444 $ 5,184,925 $ 1,128,850 $ 40,693 Increase in other non-current assets — — (134,760 ) (4,858 ) Increase (decrease) in other receivables 7,495 (735,812 ) 610,912 22,024 $ 448,939 $ 4,449,113 $ 1,605,002 $ 57,859 Payments for other intangible assets Purchase of other intangible assets $ 1,350,908 $ 982,655 $ 1,069,866 $ 38,568 Decrease in other payables 60,160 — — — $ 1,411,068 $ 982,655 $ 1,069,866 $ 38,568 b. Changes in liabilities arising from financing activities For the year ended December 31, 2019 Short-term Bonds Long-term Lease Total NT$ NT$ NT$ NT$ NT$ Balance at January 1, 2019 $ 47,163,103 $ 16,985,936 $ 137,898,329 $ 6,084,729 $ 208,132,097 Net financing cash flows (4,683,142 ) 19,279,033 1,144,731 (636,556 ) 15,104,066 Interest under operating activities — — — 1,766 1,766 Non-cash Lease liabilities — — — 536,216 536,216 Acquisition through business combinations (Note 29) 656,820 245,664 1,523,968 81,649 2,508,101 Amortization of issuance cost — 11,522 189,151 — 200,673 Lease modifications — — — (239,321 ) (239,321 ) Short-term borrowings transferred to long-term borrowings (1,499,000 ) — 1,499,000 — — Effects of foreign currency exchange (1,065,452 ) — (1,176,581 ) (19,559 ) (2,261,592 ) Balance at December 31, 2019 $ 40,572,329 $ 36,522,155 $ 141,078,598 $ 5,808,924 $ 223,982,006 For the year ended December 31, 2020 Short-term Bonds Long-term Lease Total NT$ NT$ NT$ NT$ NT$ Balance at January 1, 2020 $ 40,572,329 $ 36,522,155 $ 141,078,598 $ 5,808,924 $ 223,982,006 Net financing cash flows (1,502,323 ) 19,717,149 (26,500,139 ) (844,357 ) (9,129,670 ) Interest under operating activities — — — 111 111 Rent expense under operating activities — — — (7,729 ) (7,729 ) Non-cash Lease liabilities — — — 584,642 584,642 Amortization of issuance cost — 14,250 156,982 — 171,232 Lease modifications — — — (289,687 ) (289,687 ) Short-term borrowings transferred to long-term borrowings (3,850,000 ) — 3,850,000 — — Adjustments for government subsidy — — 41,650 — 41,650 Acquisition of subsidiaries (Note 29) 356,417 — — 633,606 990,023 Disposal of subsidiaries (Note 30) — — (4,693,682 ) (670 ) (4,694,352 ) Effects of foreign currency exchange (978,565 ) — (1,542,685 ) (9,010 ) (2,530,260 ) Balance at December 31, 2020 $ 34,597,858 $ 56,253,554 $ 112,390,724 $ 5,875,830 $ 209,117,966 For the year ended December 31, 2021 Short-term Bonds Long-term (including financial Lease Total NT$ NT$ NT$ NT$ NT$ Balance at January 1, 2021 $ 34,597,858 $ 56,253,554 $ 112,390,724 $ 5,875,830 $ 209,117,966 Net financing cash flows 10,043,398 (3,719,057 ) 16,018,825 (907,403 ) 21,435,763 Interest under operating activities — — — 800 800 Rent expense under operating activities — — — (184 ) (184 ) Convertible bonds classified separately as equity components and embedded derivative liability — (399,955 ) — — (399,955 ) Non-cash changes Lease liabilities — — — 2,037,665 2,037,665 Amortization of issuance cost — 126,283 224,979 — 351,262 Convertible bonds issued by subsidiaries and converted to ordinary shares — (102 ) — — (102 ) Lease modifications — — — (58,799 ) (58,799 ) Acquisition of subsidiaries (Note 29) — — — 180,745 180,745 Disposal of subsidiaries (Note 30) (2,443,005 ) — — (32,655 ) (2,475,660 ) Reclassification — — — 380,292 380,292 Effects of foreign currency exchange (1,161,822 ) 6,614 (2,162,038 ) (76,407 ) (3,393,653 ) Balance at December 31, 2021 $ 41,036,429 $ 52,267,337 $ 126,472,490 $ 7,399,884 $ 227,176,140 Short-term Bonds Long-term (including financial Lease Total US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Balance at January 1, 2021 $ 1,247,219 $ 2,027,886 $ 4,051,577 $ 211,818 $ 7,538,500 Net financing cash flows 362,055 (134,068 ) 577,463 (32,711 ) 772,739 Interest under operating activities — — — 29 29 Rent expense under operating activities — — — (7 ) (7 ) Convertible bonds classified separately as equity components and embedded derivative liability — (14,418 ) — — (14,418 ) Non-cash changes Lease liabilities — — — 73,456 73,456 Amortization of issuance cost — 4,553 8,110 — 12,663 Convertible bonds issued by subsidiaries and converted to ordinary shares — (4 ) — — (4 ) Lease modifications — — — (2,120 ) (2,120 ) Acquisition of subsidiaries (Note 29) — — — 6,516 6,516 Disposal of subsidiaries (Note 30) (88,068 ) — — (1,177 ) (89,245 ) Reclassification — — — 13,709 13,709 Effects of foreign currency exchange (41,883 ) 238 (77,939 ) (2,754 ) (122,338 ) Balance at December 31, 2021 $ 1,479,323 $ 1,884,187 $ 4,559,211 $ 266,759 $ 8,189,480

Capital Management

Capital Management	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Capital Management	33. CAPITAL MANAGEMENT The capital structure of the Group consists of debt and equity. The Group manages its capital to ensure that entities in the Group will be able to continue as going concerns while maximizing the return to shareholders through the optimization of the debt and equity balance. Key management personnel of the Group periodically reviews the cost of capital and the risks associated with each class of capital. In order to balance the overall capital structure, the Group may adjust the amount of dividends paid to shareholders, the number of new shares issued or repurchased, and the amount of new debt issued or existing debt redeemed. The Group is not subject to any externally imposed capital requirements except those discussed in Note 20.

Financial Instruments

Financial Instruments	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Financial Instruments	34. FINANCIAL INSTRUMENTS a. Fair value of financial instruments that are not measured at fair value 1) Fair value of financial instruments not measured at fair value but for which fair value is disclosed Except bonds payable measured at amortized cost, the management considered that the carrying amounts of financial assets and financial liabilities not measured at fair value approximate their fair values. The carrying amounts and fair value of bonds payable as of December 31, 2020 and 2021 were as follows: Carrying Amount Fair Value NT$ US$ (Note 4) NT$ US$ (Note 4) December 31, 2020 $ 56,253,554 $ 56,448,769 December 31, 2021 52,267,337 $ 1,884,187 52,429,758 $ 1,890,042 2) Fair value hierarchy The aforementioned fair value hierarchy of bonds payable was Level 3 which was determined based on discounted cash flow analysis with the applicable yield curve for the duration. The significant unobservable inputs is discount rates that reflected the credit risk. b. Fair value of financial instruments that are measured at fair value on a recurring basis 1) Fair value hierarchy Level 1 Level 2 Level 3 Total NT$ NT$ NT$ NT$ December 31, 2020 (retrospectively adjusted) Financial assets at FVTPL Derivative financial assets Forward exchange contracts $ — $ 122,511 $ — $ 122,511 Swap contracts — 99,312 — 99,312 Non-derivative Quoted ordinary shares 4,064,438 — — 4,064,438 Private-placement funds — — 1,124,754 1,124,754 Contingent considerations — — 387,790 387,790 Unquoted preferred shares — — 385,440 385,440 Open-end 339,338 — — 339,338 $ 4,403,776 $ 221,823 $ 1,897,984 $ 6,523,583 Financial assets at FVTOCI Investments in equity instruments Unquoted ordinary shares $ — $ — $ 567,377 $ 567,377 Unquoted preferred shares — — 151,329 151,329 Limited partnership — — 9,692 9,692 Investments in debt instruments Unsecured subordinate corporate bonds — — 1,012,736 1,012,736 Trade receivables, net — — 626,413 626,413 $ — $ — $ 2,367,547 $ 2,367,547 Financial liabilities at FVTPL Derivative financial liabilities Swap contracts $ — $ 1,448,972 $ — $ 1,448,972 Target redemption forward contracts — 79,216 — 79,216 Forward exchange contracts — 9,020 — 9,020 $ — $ 1,537,208 $ — $ 1,537,208 Level 1 Level 2 Level 3 Total NT$ US$ (Note 4) NT$ US$ (Note 4) NT$ US$ (Note 4) NT$ US$ (Note 4) December 31, 2021 Financial assets at FVTPL Derivative financial assets Swap contracts $ — $ — $ 85,629 $ 3,087 $ — $ — $ 85,629 $ 3,087 Forward exchange contracts — — 23,373 843 — — 23,373 843 Redemption option and put option of convertible bonds — — 8,463 305 — — 8,463 305 Target redemption forward contracts — — 500 18 — — 500 18 Non-derivative Quoted ordinary shares 2,683,193 96,726 — — — — 2,683,193 96,726 Private-placement funds — — — — 1,322,686 47,682 1,322,686 47,682 Unquoted preferred shares — — — — 583,270 21,026 583,270 21,026 Conti n — — — — 394,943 14,237 394,943 14,237 Open-end 334,223 12,049 — — — — 334,223 12,049 $ 3,017,416 $ 108,775 $ 117,965 $ 4,253 $ 2,300,899 $ 82,945 $ 5,436,280 $ 195,973 Financial assets at FVTOCI Investments in equity instruments Unquoted ordinary shares $ — $ — $ — $ — $ 820,779 $ 29,588 $ 820,779 $ 29,588 Quoted ordinary shares 102,124 3,682 — — — — 102,124 3,682 Unquoted preferred shares — — — — 11,245 405 11,245 405 Limited partnership — — — — 9,206 332 9,206 332 Investments in debt instruments Unsecured subordinate corporate bonds — — — — 1,076,458 38,805 1,076,458 38,805 Trade receivables, net — — — — 6,092,462 219,627 6,092,462 219,627 $ 102,124 $ 3,682 $ — $ — $ 8,010,150 $ 288,757 $ 8,112,274 $ 292,439 Financial liabilities at FVTPL Derivative financial liabilities Swap contracts $ — $ — $ 360,797 $ 13,006 $ — $ — $ 360,797 $ 13,006 Forward exchange contracts — — 56,863 2,050 — — 56,863 2,050 $ — $ — $ 417,660 $ 15,056 $ — $ — $ 417,660 $ 15,056 For the financial assets and liabilities that were measured at fair value on a recurring basis, there were no transfers between Level 1 and Level 2 of the fair value hierarchy during the years ended December 31, 2020 and 2021. 2) Reconciliation of Level 3 fair value measurements of financial assets For the year ended December 31, 2019 Financial Assets at FVTPL Financial Assets at FVTOCI Financial Assets Equity Instruments Equity Debt Total NT$ NT$ NT$ NT$ Balance at January 1 $ 475,123 $ 580,399 $ 1,016,924 $ 2,072,446 Recognized in profit or loss 3,431 — — 3,431 Recognized in other comprehensive income Included in unrealized losses on financial assets at FVTOCI — (216,121 ) (2,052 ) (218,173 ) Effects of foreign currency exchange (14,368 ) (5,695 ) — (20,063 ) Net increase in trade receivables — — 3,171,205 3,171,205 Trade receivables factoring — — (1,141,515 ) (1,141,515 ) Purchases 541,528 409,985 — 951,513 Disposals — (12,665 ) — (12,665 ) Balance at December 31 $ 1,005,714 $ 755,903 $ 3,044,562 $ 4,806,179 For the year ended December 31, 2020 Financial Assets at FVTPL Financial Assets at FVTOCI Financial Assets Equity Debt Equity Debt Total NT$ NT$ NT$ NT$ NT$ Balance at January 1 $ 1,005,714 $ — $ 755,903 $ 3,044,562 $ 4,806,179 Recognized in profit or loss (17,941 ) — — — (17,941 ) Recognized in other comprehensive income Included in unrealized losses on financial assets at FVTOCI — — (149,856 ) (2,136 ) (151,992 ) Effects of foreign currency exchange (15,455 ) — (15,562 ) — (31,017 ) Net increase in trade receivables — 370,110 — 5,635,706 6,005,816 Trade receivables factoring — (370,110 ) — (7,038,983 ) (7,409,093 ) Purchases 893,234 — 259,168 — 1,152,402 Disposals (329,370 ) — (121,255 ) — (450,625 ) Acquisition through business combinations 387,790 — — — 387,790 Exercise of call option (25,988 ) — — — (25,988 ) Balance at December 31 (retrospectively adjusted) $ 1,897,984 $ — $ 728,398 $ 1,639,149 $ 4,265,531 For the year ended December 31, 2021 Financial Assets at FVTPL Financial Assets at FVTOCI Financial Assets Equity Debt Equity Debt Total NT$ NT$ NT$ NT$ NT$ Balance at January 1 (retrospectively adjusted) $ 1,897,984 $ — $ 728,398 $ 1,639,149 $ 4,265,531 Recognized in profit or loss 131,276 — — — 131,276 Recognized in other comprehensive income Included in unrealized losses on financial assets at FVTOCI — — 129,726 63,722 193,448 Effects of foreign currency exchange (79,614 ) — (4,508 ) — (84,122 ) Net increase in trade receivables — 3,269,782 — 14,940,539 18,210,321 Trade receivables factoring — (3,269,782 ) — (9,474,490 ) (12,744,272 ) Purchases 459,046 — 32,246 — 491,292 Disposals (107,793 ) — (14,873 ) — (122,666 ) Reclassify — — (29,758 ) — (29,758 ) Balance at December 31 $ 2,300,899 $ — $ 841,231 $ 7,168,920 $ 10,311,050 Financial Assets at FVTPL Financial Assets at FVTOCI Financial Assets Equity Debt Equity Debt Total US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ Balance at January 1 (retrospect ively adjusted) $ 68,421 $ — $ 26,257 $ 59,089 $ 153,767 Recognized in profit or loss 4,732 — — — 4,732 Recognized in other comprehensive income Included in unrealized losses on financial assets at FVTOCI — — 4,677 2,297 6,974 Effects of foreign currency exchange (2,870 ) — (163 ) — (3,033 ) Net increase in trade receivables — 117,872 — 538,592 656,464 Trade receivables factoring — (117,872 ) — (341,546 ) (459,418 ) Purchases 16,548 — 1,163 — 17,711 Disposals (3,886 ) — (536 ) — (4,422 ) Reclassify — — (1,073 ) — (1,073 ) Balance at December 31 $ 82,945 $ — $ 30,325 $ 258,432 $ 371,702 3) Valuation techniques and assumptions applied for the purpose of measuring fair value a) Valuation techniques and inputs applied for the purpose of measuring Level 2 fair value measurement Financial Instruments Valuation Techniques and Inputs Derivatives - swap contracts and forward exchange contracts Discounted cash flows - Future cash flows are estimated based on observable forward exchange rates at balance sheet dates and contract forward exchange rates, discounted at rates that reflected the credit risk of various counterparties. Derivatives - redemption option and put option of convertible bonds Option pricing models – Use of present value techniques and reflect the time value and intrinsic value of redemption option and put option. Target redemption forward contracts Valuation based on the spot exchange rate on the valuation date, the exercise price, the volatility in exchange rate, the contract period and the quoted risk free interest rate during the contract period. b) Valuation techniques and inputs applied for the purpose of measuring Level 3 fair value measurement The fair value of unquoted ordinary shares, unquoted preferred shares, limited partnership and private-placement funds were determined by using market approach and asset-based approach. The significant unobservable inputs were the discount rates for lack of marketability of 10% to 30%. If the discount rates for lack of marketability to the valuation model increased by 1% to reflect reasonably possible alternative assumptions while all other variables held constant, the fair value of the abovementioned investments would have decreased approximately by NT$9,700 thousand and NT$19,300 thousand (US$696 thousand) as of December 31, 2020 and 2021, respectively. The fair values of the unsecured subordinate corporate bonds were determined using income approach based on a discounted cash flow analysis. The significant unobservable input was the discount rate that reflects the credit risk of the counterparty. If the discount rate increased by 0.1% while all other variables held constant, the fair value of the bonds would have decreased approximately by NT$5,000 thousand and NT$4,000 thousand (US$144 thousand) as of December 31, 2020 and 2021, respectively. The fair value of accounts receivables measured at FVTOCI are determined based on the present value of future cash flows that reflect the credit risk of counterparties. Since the discount effect was not significant, the Group measured its fair value by using the nominal values. The fair value of the contingent considerations were determined by using the Monte Carlo Simulation method. If the estimated net profit margin fails to reach the performance specified in the agreement, the Group could receive the contingent considerations according to the agreement, refer to Note 29 for business combinations. c. Categories of financial instruments December 31 2020 (Retrospectively 2021 NT$ NT$ US$ (Note 4) Financial assets FVTPL Mandatorily at FVTPL $ 6,523,583 $ 5,436,280 $ 195,973 Measured at amortized cost (Note 1) 147,521,583 200,732,680 7,236,218 FVTOCI Equity instruments 728,398 943,354 34,007 Debt instruments 1,012,736 1,076,458 38,805 Trade receivables, net 626,413 6,092,462 219,627 Financial liabilities FVTPL Held for trading 1,537,208 417,660 15,056 Financial liabilities for hedging 11,188,244 11,497,896 414,488 Measured at amortized cost (Note 2) 304,737,749 339,445,544 12,236,683 Note 1: The balances included financial assets measured at amortized cost which comprised cash and cash equivalents, trade and other receivables and other financial assets. Note 2: The balances included financial liabilities measured at amortized cost which comprised short-term borrowings, trade and other payables, bonds payable and long-term borrowings. d. Financial risk management objectives and policies The derivative instruments used by the Group were to mitigate risks arising from ordinary business operations. All derivative transactions entered into by the Group were designated as either hedging or trading. Derivative transactions entered into for hedging purposes must hedge risk against fluctuations in foreign exchange rates and interest rates arising from operating activities. The currencies and the amount of derivative instruments held by the Group must match its hedged assets and liabilities denominated in foreign currencies. The Group’s risk management department monitored risks to mitigate risk exposures, reported unsettled position, transaction balances and related gains or losses to the Group’s chief financial officer on monthly basis. 1) Market risk The Group’s activities exposed it primarily to the financial risks of changes in foreign currency exchange rates and interest rates. Gains or losses arising from fluctuations in foreign currency exchange rates of a variety of derivative financial instruments were approximately offset by those of hedged items. Interest rate risk was not significant due to the cost of capital was expected to be fixed. There had been no change to the Group’s exposure to market risks or the manner in which these risks were managed and measured. a) Foreign currency exchange rate risk The Group had sales and purchases as well as financing activities denominated in foreign currency which exposed the Group to foreign currency exchange rate risk. The Group entered into a variety of derivative financial instruments to hedge foreign currency exchange rate risk to minimize the fluctuations of assets and liabilities denominated in foreign currencies. The carrying amounts of the Group’s foreign currency denominated monetary assets and liabilities (including those eliminated upon consolidation) as well as derivative instruments which exposed the Group to foreign currency exchange rate risk at each balance sheet date are presented in Note 39 The Group was mainly subject to the impact from the exchange rate fluctuation in US$ and JPY against NT$, RMB or EUR. 1% fluctuation is used when reporting foreign currency exchange rate risk internally to key management personnel and represents management’s assessment of the reasonably possible change in foreign currency exchange rates. The sensitivity analysis included financial assets and liabilities and inter-company receivables and payables within the Group. The changes in profit before income tax due to a 1% change in US$ and JPY against NT$, RMB and EUR would be NT$82,000 thousand, NT$35,000 thousand and NT$38,000 thousand (US$1,370 thousand) for the years ended December 31, 2019, 2020 and 2021, respectively. Hedging contracts and hedged items have been taken into account while measuring the changes in profit before income tax. The abovementioned sensitivity analysis mainly focused on the foreign currency monetary items at each balance sheet date. As the period-end Hedge accounting The Group’s hedging strategy was to lift borrowings denominated in foreign currencies to avoid exchange rate exposure from its investments in equity instruments denominated in foreign currencies (recognized under the line item of financial assets at FVTPL) and net investment in foreign subsidiary, USIFR, which has EUR as its functional currency. Those transactions were designated as fair value hedges and a hedge of net investment in foreign operation, respectively. Hedge adjustments were made to totally offset the foreign exchange gains or losses from those equity instruments denominated in foreign currencies and foreign operations when they were evaluated based on the exchange rates on each balance sheet date. The hedge ineffectiveness in these hedging relationships arose from the material difference between the notional amounts of borrowings denominated in foreign currencies and the original investments in equity instruments denominated in foreign currencies and net investment in foreign operations. No other sources of ineffectiveness is expected to emerge from these hedging relationships. December 31, 2020 Hedging Instrument/Hedged Items Line item in Carrying Amount Balance sheet Asset Liability NT$ NT$ Fair value hedge Borrowings denominated in foreign currencies/ Financial assets at FVTPL Financial liabilities for hedging - current $ — $ 3,307,018 Hedge of net investment in foreign operation Financial liabilities for hedging - current — 1,970,307 Hedge of net investment in foreign operation Financial liabilities for hedging - non-current — 5,910,919 Change in Value Used for Calculating Hedge Ineffectiveness Accumulated Gains or Losses in Other Equity Carrying Accumulated Hedging Instrument/Hedged Item Hedging Hedged Item Continuing Hedge Asset Asset NT$ NT$ NT$ NT$ NT$ NT$ Fair value hedge Borrowings denominated in foreign currencies/ Financial assets at FVTPL $ 157,842 $ (157,842 ) $ — $ — $ 2,859,132 $ (142,217 ) Hedge of net investment in foreign operation 574,824 (574,824 ) (574,824 ) — — — December 31, 2021 Hedging Instrument/Hedged Items Line item in Carrying Amount Balance sheet Asset Liability NT$ US$ (Note 4) NT$ US$ (Note 4) Fair value hedge Borrowings denominated in foreign currencies/ Financial assets at FVTPL Financial liabilities for hedging - current $ — $ — $ 2,954,921 $ 106,522 Hedge of net investment in foreign operation Financial liabilities for hedging - current — — 3,762,044 135,618 Hedge of net investment in foreign operation Financial liabilities for hedging - non-current — — 4,780,931 172,348 Change in Value Used for Calculating Hedge Ineffectiveness Accumulated Gains or Losses in Other Equity Carrying Accumulated Hedging Instrument/Hedged Item Hedging Hedged Continuing Hedge Asset Asset NT$ NT$ NT$ NT$ NT$ NT$ Fair value hedge Borrowings denominated in foreign currencies/ Financial assets at FVTPL $ 94,145 $ (94,145) $ — $ — $ 2,318,517 $ (236,362) Hedge of net investment in foreign operation (738,600 ) 738,600 163,776 — — — Change in Value Used for Calculating Hedge Ineffectiveness Accumulated Gains or Losses in Other Equity Carrying Accumulated Hedging Instrument/ Hedged Item Hedging Hedged Item Continuing Hedge Asset Asset US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Fair value hedge Borrowings denominated in foreign currencies/ Financial assets at FVTPL $ 3,394 $ (3,394 ) $ — $ — $ 83,580 $ (8,521 ) Hedge of net investment in foreign operation (26,626 ) 26,626 5,904 — — — b) Interest rate risk Except a portion of long-term borrowings and bonds payable at fixed interest rates, the Group was exposed to interest rate risk because group entities borrowed funds at floating interest rates. Changes in market interest rates led to variances in effective interest rates of borrowings from which the future cash flow fluctuations arise. The Group utilized financing instruments with low interest rates and favorable terms to maintain low financing cost, adequate banking facilities, as well as to hedge interest rate risk. The carrying amounts of the Group’s financial assets and financial liabilities with exposure to interest rates at each balance sheet date were as follows: December 31 2020 2021 NT$ NT$ US$ (Note 4) Fair value interest rate risk Financial assets $ 5,049,005 $ 5,474,105 $ 197,336 Financial liabilities 56,599,417 76,206,394 2,747,166 Cash flow interest rate risk Financial assets 45,489,788 69,654,969 2,510,994 Financial liabilities 131,715,366 158,557,225 5,715,834 For assets and liabilities with floating interest rates, a 100 basis point increase or decrease was used when reporting interest rate risk internally to key management personnel. If interest rates had been 100 basis points (1%) higher or lower and all other variables held constant, the Group’s profit before income tax for the years ended December 31, 2019, 2020 and 2021 would have decreased or increased approximately by NT$ thousand, NT$ thousand and NT$ thousand (US$ thousand), respectively. Hedging contracts and hedged items have been taken into account while measuring the changes in profit before income tax. The abovementioned sensitivity analysis mainly focused on the interest rate items at the end of each year. As the year-end exposure did not reflect the exposure for the years ended December , , and , the abovementioned sensitivity analysis was unrepresentative of those respective periods. c) Other price risk The Group was exposed to equity price risk through its investments in financial assets at FVTPL and financial assets at FVTOCI. If equity price was 1% higher or lower, profit before income tax for the years ended December 31, 2019, 2020 and 2021 would have increased or decreased approximately by NT$51,000 thousand, NT$59,000 thousand and NT$49,000 thousand (US$1,766 thousand), respectively, and other comprehensive income before income tax for the years ended December 31, 2019, 2020 and 2021 would have increased or decreased approximately by NT$8,000 thousand, NT$7,000 thousand and NT$9,000 thousand (US$324 thousand), respectively. 2) Credit risk Credit risk refers to the risk that counterparty will default on its contractual obligations resulting in financial loss to the Group. The Group’s credit risk arises from cash and cash equivalents, trade and other receivables and other financial assets. The Group’s maximum exposure to credit risk was the carrying amounts of financial assets in the consolidated balance sheets. As of December 31, 2020 and 2021, the Group’s five largest customers accounted for 27% and 33% of trade receivables, respectively. The Group transacts with a large number of unrelated customers and, thus, no concentration of credit risk was observed. 3) Liquidity risk The Group manages liquidity risk by maintaining adequate working capital and banking facilities to fulfill the demand for cash flow used in the Group’s operation and capital expenditure. The Group also monitors its compliance with all the loan covenants. Liquidity risk is not considered to be significant. In the table below, financial liabilities with a repayment on demand clause were included in the earliest time band regardless of the probability of counter-parties choosing to exercise their rights. The maturity dates for other non-derivative To the extent that interest flows are floating rate, the undiscounted amounts were derived from the interest rates at each balance sheet date. December 31, 2020 On Demand or 1 Month 1 to 3 3 Months 1 Year 1 to 5 Years More than 5 Years NT$ NT$ NT$ NT$ NT$ Non-derivative Non-interest $ 43,111,390 $ 44,122,659 $ 8,223,684 $ 319,510 $ 176,536 Obligation under leases 103,734 151,921 619,908 1,779,041 4,088,301 Floating interest rate liabilities 13,792,596 8,190,076 10,214,154 102,253,481 7,999,130 Fixed interest rate liabilities 11,895,281 528,290 3,349,614 46,900,450 5,631,522 $ 68,903,001 $ 52,992,946 $ 22,407,360 $ 151,252,482 $ 17,895,489 Further information for maturity analysis of obligation under leases was as follows: Less than 1 Year 1 to 5 5 to 10 10 to 15 Years 15 to 20 Years More than 20 Years NT$ NT$ NT$ NT$ NT$ NT$ Obligation under leases $ 875,563 $ 1,779,041 $ 1,422,331 $ 776,735 $ 674,446 $ 1,214,789 December 31, 2021 On Demand or 1 Month 1 to 3 Months 3 Months to 1 Year 1 to 5 Years More than 5 Years NT$ NT$ NT$ NT$ NT$ Non-derivative financial liabilities Non-interest $ 52,353,176 $ 48,140,652 $ 10,216,253 $ 291,480 $ 114,201 Obligation under leases 84,978 157,710 687,144 2,585,624 4,929,602 Floating interest rate liabilities 12,565,548 5,180,527 13,416,893 112,493,242 7,494,670 Fixed interest rate liabilities 10,262,781 3,093,668 12,978,593 43,555,458 5,479,867 $ 75,266,483 $ 56,572,557 $ 37,298,883 $ 158,925,804 $ 18,018,340 On Demand or 1 Month 1 to 3 Months 3 Months to 1 Year 1 to 5 Years More than 5 Years US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Non-derivative financial liabilities Non-interest $ 1,887,281 $ 1,735,424 $ 368,286 $ 10,508 $ 4,117 Obligation under leases 3,063 5,685 24,771 93,209 177,707 Floating interest rate liabilities 452,976 186,753 483,666 4,055,272 270,176 Fixed interest rate liabilities 369,963 111,524 467,866 1,570,132 197,544 $ 2,713,283 $ 2,039,386 $ 1,344,589 $ 5,729,121 $ 649,544 Further information for maturity analysis of obligation under leases was as follows: Less than 1 Year 1 to 5 Years 5 to 10 Years 10 to 15 Years 15 to 20 Years More than 20 Years NT$ NT$ NT$ NT$ NT$ NT$ Obligation under leases $ 929,832 $ 2,585,624 $ 1,731,995 $ 883,335 $ 802,765 $ 1,511,507 Less than 1 Year 1 to 5 Years 5 to 10 Years 10 to 15 Years 15 to 20 Years More than 20 Years US$ US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Obligation under leases $ 33,519 $ 93,209 $ 62,437 $ 31,843 $ 28,939 $ 54,488 The amounts included above for floating interest rate instruments for non-derivative The following table detailed the Group’s liquidity analysis for its derivative financial instruments. The table was based on the undiscounted contractual net cash inflows and outflows on derivative instruments settled on a net basis, and the undiscounted gross cash inflows and outflows on those derivatives that require gross settlement. When the amounts payable or receivable are not fixed, the amounts disclosed have been determined by reference to the projected interest rates as illustrated by the yield curves at each balance sheet date. On Demand 1 Month 1 to 3 3 Months to 1 Year More than NT$ NT$ NT$ December 31, 2020 Net settled Forward exchange contracts $ 30,514 $ 18,429 $ — $ — Gross settled Forward exchange contracts Inflows $ 8,862,682 $ 5,565,137 $ 531,336 $ — Outflows (8,798,238 ) (5,518,153 ) (526,880 ) — 64,444 46,984 4,456 — Swap contracts Inflows 19,311,999 17,179,871 36,739,200 — Outflows (19,524,820 ) (17,486,997 ) (37,495,172 ) — (212,821 ) (307,126 ) (755,972 ) — Target redemption forward contracts Inflows 42,720 96,120 416,520 227,128 Outflows (44,471 ) (100,060 ) (433,595 ) (236,081 ) (1,751 ) (3,940 ) (17,075 ) (8,953 ) $ (150,128 ) $ (264,082 ) $ (768,591 ) $ (8,953 ) On Demand or 1 Month 1 to 3 Months 3 Months to 1 Year NT$ NT$ NT$ December 31, 2021 Net settled Forward exchange contracts $ (21,379 ) $ (1,410 ) $ — Gross settled Forward exchange contracts Inflows $ 2,382,315 $ 6,817,411 $ 531,596 Outflows (2,380,359 ) (6,784,689 ) (525,920 ) 1,956 32,722 5,676 Swap contracts Inflows 23,759,435 21,272,450 37,841,805 Outflows (23,814,701 ) (21,314,442 ) (37,965,438 ) (55,266 ) (41,992 ) (123,633 ) Target redemption forward contracts Inflows 19,376 43,596 33,216 Outflows (18,845 ) (42,401 ) (32,243 ) 531 1,195 973 $ (52,779 ) $ (8,075 ) $ (116,984 ) On Demand or 1 Month 1 to 3 Months 3 Months to US$ (Note 4) US$ (Note 4) US$ (Note 4) December 31, 2021 Net settled Forward exchange contracts $ (771 ) $ (51 ) $ — Gross settled Forward exchange contracts Inflows $ 85,880 $ 245,761 $ 19,164 Outflows (85,810 ) (244,581 ) (18,959 ) 70 1,180 205 Swap contracts Inflows 856,505 766,851 1,364,160 Outflows (858,497 ) (768,365 ) (1,368,617 ) (1,992 ) (1,514 ) (4,457 ) Target redemption forward contracts Inflows 698 1,572 1,197 Outflows (679 ) (1,529 ) (1,162 ) 19 43 35 $ (1,903 ) $ (291 ) $ (4,217 )

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Related Party Transactions	35. RELATED PARTY TRANSACTIONS Balances and transactions within the Group had been eliminated upon consolidation. Details of transactions between the Group and other related parties were disclosed as follows: a. Related parties In addition to those disclosed in Note 14, the related parties were as follows: Name of Related Party Relationship with the Company ASE Cultural and Educational Foundation Substantial related party ASE Environmental Protection and Sustainability Foundation Substantial related party b. Contribution of related party For the Year Ended December 31 Relationship and Name of Related Party 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Substantial related party ASE Cultural and Educational Foundation $ 100,000 $ — $ 10,000 $ 360 ASE Environmental Protection and Sustainability Foundation — 100,000 100,000 3,605 $ 100,000 $ 100,000 $ 110,000 $ 3,965 c. In 2019, the subsidiary, ASE, purchased real estate properties from associates, HC, with the amount of NT$2,326,000 thousand, which was primarily based on the independent professional appraisal reports and had d. ASE and HC entered into a joint development agreement in June 2020 under the concept of joint construction. The agreement stipulates that HC will build the plant on the leasehold land and ASE and its affiliates will have the priority to purchase the plant after the completion of the plant construction. The final transaction price will be the purchase price less an amount based on the ratio calculated by independent professional appraisers. e. In the third quarter of 2021, ASE purchased real estate properties from HC had f. The subsidiaries, ASE and ASEE, separately entered into a joint construction and allocation of housing units agreement with HC in August 2021. The agreement stipulates that ASE and ASEE will provide land or leasehold land and fund to HC for plant construction and to allocate those housing units based on the independent professional appraisal reports. After the completion of the plant construction, ASE, ASEE and its affiliates will have the priority to purchase the plant. g. As disclosed in Note 31, USIE repurchased its own 2,805 thousand, 2,685 thousand and 2,271 thousand ordinary shares from the Group’s key management personnel with approximately NT$1,247,187 thousand, NT$1,520,976 thousand and NT$1,081,214 thousand (US$38,977 thousand) in July 2019, September 2020 and December 2021, respectively. h. Compensation to key management personnel For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Short-term employee benefits $ 1,027,191 $ 1,264,980 $ 1,744,903 $ 62,902 Post-employment benefits 2,208 2,007 3,505 126 Share-based payments 134,544 153,774 163,697 5,901 $ 1,163,943 $ 1,420,761 $ 1,912,105 $ 68,929 The compensation to the Group’s key management personnel was determined according to personal performance and market trends.

Assets Pledged as Collateral or

Assets Pledged as Collateral or for Security	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Assets Pledged as Collateral or for Security	36. ASSETS PLEDGED AS COLLATERAL OR FOR SECURITY The following assets were provided as collateral for bank borrowings, tariff guarantees of imported raw materials or collateral: December 31 2020 2021 NT$ NT$ US$ (Note 4) Inventories related to real estate business $ 10,564,873 $ 2,587,110 $ 93,263 Property, plant and equipment 124,124 114,390 4,124 Investment properties 11,847,145 20,796,862 749,707 Other financial assets (including current and non-current) 460,890 444,358 16,018 $ 22,997,032 $ 23,942,720 $ 863,112 In addition to the abovementioned assets, 89.6% of shareholdings in FAFG was provided as collateral for syndicated bank loans as of December 31, 2020.

Significant Contingent Liabilit

Significant Contingent Liabilities and Unrecognized Commitments	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Significant Contingent Liabilities and Unrecognized Commitments	37. SIGNIFICANT CONTINGENT LIABILITIES AND UNRECOGNIZED COMMITMENTS In addition to those disclosed in other notes, significant commitments and contingencies of the Group as of each balance sheet date were as follows: a. As of December 31, 2020 and 2021, unused letters of credit of the Group were approximately NT$2,000 thousand and NT$74,000 thousand (US$2,668 thousand), respectively. b. As of December 31, 2020 and 2021, letters of bank guarantee impo rt and export with b ank c. As of December 31, 2020 and 2021, the Group’s commitments to purchase property, plant and equipment were approximately NT$32,627,411 thousand and NT$52,678,554 thousand (US$1,899,011 thousand), respectively, of which NT$1,968,779 thousand and NT$3,761,120 thousand (US$135,585 thousand) had been prepaid, respectively. As of December 31, 2020 and 2021, the commitment that the Group has contracted for the construction related to real estate business were approximately NT$602,548 thousand and NT$59 thousand (US$2 thousand), respectively. d. The Group entered into long-term purchase agreements of materials and supplies with multiple suppliers. The relative minimum purchase quantity is specified in the agreements. e. The Group entered into long-term agreements with multiple customers. The relative minimum order quantity to customers f. In December 2021, in consideration of corporate social responsibility, the board of directors resolved disbursements thousand) to ASE Cultural and Educational Foundation for promoting the cultural and educational activities to discharge the Group’s social responsibilities. g. In December 2013, in consideration of corporate social responsibility for environmental protection, the board of directors of ASE, approved the contributions of at least NT$100,000 thousand (US$3,605 thousand) annually to be made in the next 30 years, with a total amount of at least NT$3,000,000 thousand (US$108,147 thousand), for promoting environmental protection efforts in Taiwan. In December 2021, the board of directors of ASE resolved to contribute NT$100,000 thousand (US$3,605 thousand) to ASE Environmental Protection and Sustainability Foundation.

Others

Others	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Others	38. OTHERS a. There were five employees and a waste disposal supplier of a subsidiary in China accused by China People’s Procuratorate (the “Procuratorate”) for committing the crime of environmental pollution in 2018. During the trial, the Procuratorate claimed that the subsidiary should also be charged with corporate crime which caused the subsidiary received a change and addition indictment in October 20 19 co-defendants b. On December 20, 2013, the Kaohsiung Environmental Protection Bureau (the “KEPB”) imposed an administrative fine of NT$102,014 thousand (the “Original Fine”) upon ASE for violation of the Water Pollution Control Act. After ASE sought administrative remedies against the Original Fine, the Original Fine has been revoked by final judgment of Supreme Administrative Court on June 8, 2017, and KEPB is ordered to refund the Original Fine to ASE. On December 27, 20 19 re-imposed

Significant Assets and Liabilit

Significant Assets and Liabilities Denominated in Foreign Currencies	12 Months Ended
	Dec. 31, 2021
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Significant Assets and Liabilities Denominated in Foreign Currencies	39 SIGNIFICANT ASSETS AND LIABILITIES DENOMINATED IN FOREIGN CURRENCIES The following information was aggregated by the foreign currencies other than functional currencies of the group entities and the exchange rates between foreign currencies and respective functional currencies were disclosed. The significant financial assets and liabilities denominated in foreign currencies were as follows: Foreign (In Thousand) Exchange Rate Carrying Amount (In Thousand) December 31, 2020 Monetary financial assets US$ $ 4,269,075 US$1=NT$28.48 $ 121,583,265 US$ 1,527,381 US$1=RMB6.5249 43,499,803 US$ 41,643 US$1=EUR0.8143 1,185,984 JPY 13,544,360 JPY1=NT$0.2763 3,742,306 JPY 1,174,208 JPY1=US$0.0097 324,434 HKD 174,765 HKD1=NT$3.6730 641,912 Monetary financial liabilities US$ 4,439,915 US$1=NT$28.48 126,448,786 US$ 1,517,568 US$1=RMB6.5249 43,220,325 US$ 20,896 US$1=EUR0.8143 595,128 JPY 13,657,967 JPY1=NT$0.2763 3,773,695 JPY 1,188,650 JPY1=US$0.0097 328,424 HKD 18,814 HKD1=NT$3.6730 69,103 December 31, 2021 Monetary financial assets US$ 4,885,163 US$1=NT$27.68 135,221,324 US$ 1,718,314 US$1=RMB6.3757 47,562,940 US$ 42,250 US$1=EUR0.8829 1,169,492 JPY 12,584,942 JPY1=NT$0.2405 3,026,677 JPY 551,496 JPY1=US$0.0087 132,635 Monetary financial liabilities US$ 4,899,633 US$1=NT$27.68 135,621,853 US$ 1,503,606 US$1=RMB6.3757 41,619,803 US$ 88,741 US$1=EUR0.8829 2,456,363 JPY 14,078,075 JPY1=NT$0.2405 3,385,776 JPY 990,667 JPY1=US$0.0087 238,255 The significant realized and unrealized foreign exchange gain (loss) were as follows: For the Year Ended December 31 2019 2020 2021 Functional Currencies Exchange Rate Net Foreign Exchange Rate Net Foreign Exchange Rate Net Foreign Exchange Gain (Loss) NT$ NT$ NT$ US$ (Note 4) US$ US$1=NT$29.98 $ (84,177 ) US$1=NT$28.48 $ (143,804 ) US$1=NT$27.68 $ 132,582 $ 4,780 NT$ 1,203,823 1,382,067 1,413,969 50,972 RMB RMB1=NT$4.2975 14,055 RMB1=NT$4.3648 (181,624 ) RMB1=NT$4.3415 (85,675 ) (3,089 ) $ 1,133,701 $ 1,056,639 $ 1,460,876 $ 52,663

Operating Segments Information

Operating Segments Information	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Operating Segments Information	4 0 OPERATING SEGMENTS INFORMATION The Group has the following reportable segments: Packaging, Testing and EMS. The Group packages bare semiconductors into finished semiconductors with enhanced electrical and thermal characteristics; provides testing services, including front-end The accounting policies for segments are the same as those described in Note 4. The measurement basis for resources allocation and performance evaluation is based on profit before income tax. a. Segment revenues and operation results Adjustments Packaging Testing EMS Others and Eliminations Total NT$ NT$ NT$ NT$ NT$ NT$ For the year ended December 31, 2019 Revenue from external customers $ 198,916,897 $ 42,658,686 $ 165,789,479 $ 5,817,122 $ — $ 413,182,184 Inter-group revenues (Note 1) 5,370,963 231,399 60,638,567 7,431,399 (73,672,328 ) — Segment revenues 204,287,860 42,890,085 226,428,046 13,248,521 — 486,854,512 Interest income 186,291 90,091 249,487 284,458 (260,646 ) 549,681 Interest expense (3,403,475 ) (545,609 ) (255,404 ) (243,013 ) 260,646 (4,186,855 ) Depreciation and amortization (33,456,831 ) (12,379,703 ) (2,534,825 ) (2,095,482 ) — (50,466,841 ) Share of the profit or loss of associates and joint ventures 75,303 39,852 67,120 — — 182,275 Impairment loss (601,066 ) (141 ) — — — (601,207 ) Segment profit before income tax 7,572,763 10,321,537 6,082,106 (696,595 ) — 23,279,811 Expenditures for segment assets 35,462,305 23,966,051 2,770,129 875,402 — 63,073,887 December 31, 2019 Investments accounted for using the equity method 8,867,316 1,123,490 2,094,401 — — 12,085,207 Contract assets 4,162,124 1,735,192 — — — 5,897,316 For the year ended December 31, 2020 Revenue from external customers 218,666,071 47,271,074 204,690,669 6,350,896 — 476,978,710 Inter-group revenues (Note 1) 10,436,168 435,587 21,472,775 7,234,303 (39,578,833 ) — Segment revenues 229,102,239 47,706,661 226,163,444 13,585,199 — 516,557,543 Interest income 133,160 79,821 275,766 32,036 — 520,783 Interest expense (2,244,280 ) (564,269 ) (443,519 ) (185,160 ) — (3,437,228 ) Depreciation and amortization (32,333,229 ) (14,189,024 ) (2,877,546 ) (1,859,266 ) — (51,259,065 ) Share of the profit or loss of associates and joint ventures 362,133 99,670 85,809 — — 547,612 Impairment loss (218,600 ) (773,673 ) — — — (992,273 ) Segment profit before income tax 17,476,440 10,277,760 8,438,766 (424,168 ) — 35,768,798 Expenditures for segment assets 38,643,303 14,275,397 5,614,409 491,092 — 59,024,201 December 31, 2020 Investments accounted for using the equity method 9,146,344 1,340,307 2,320,022 — — 12,806,673 Contract assets 3,641,244 1,141,660 — — — 4,782,904 For the year ended December 31, 2021 Revenue from external customers 272,543,899 49,978,736 239,488,267 7,986,231 — 569,997,133 Inter-group revenues (Note 1) 7,244,889 339,619 27,825,073 7,527,260 (42,936,841 ) — Segment revenues 279,788,788 50,318,355 267,313,340 15,513,491 — 612,933,974 Interest income 61,141 88,874 301,072 91,242 — 542,329 Interest expense (1,604,107 ) (405,648 ) (629,584 ) (159,596 ) — (2,798,935 ) Depreciation and amortization (34,384,500 ) (13,819,080 ) (4,336,266 ) (1,984,431 ) — (54,524,277 ) Share of the profit or loss of associates and joint ventures 737,650 66,107 95,943 — — 899,700 Impairment loss (86,997 ) (39,769 ) — — — (126,766 ) Segment profit before income tax 41,581,126 11,998,938 8,528,675 18,085,030 — 80,193,769 Expenditures for segment assets 48,531,368 16,773,513 7,654,560 1,458,100 — 74,417,541 December 31, 2021 Investments accounted for using the equity method 12,744,756 1,896,372 2,355,472 — — 16,996,600 Contract assets 4,735,181 872,028 — — — 5,607,209 Adjustments Packaging Testing EMS Others and Eliminations Total US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) For the year ended December 31, 2021 Revenue from external customers $ 9,824,942 $ 1,801,685 $ 8,633,319 $ 287,896 $ — $ 20,547,842 Inter-group revenues (Note 1) 261,171 12,243 1,003,067 271,350 (1,547,831 ) — Segment revenues 10,086,113 1,813,928 9,636,386 559,246 — 22,095,673 Interest income 2,204 3,204 10,853 3,289 — 19,550 Interest expense (57,827 ) (14,623 ) (22,696 ) (5,753 ) — (100,899 ) Depreciation and amortization (1,239,528 ) (498,164 ) (156,318 ) (71,537 ) — (1,965,547 ) Share of the profit or loss of associates and joint ventures 26,591 2,383 3,459 — — 32,433 Impairment loss (3,137 ) (1,434 ) — — — (4,571 ) Segment profit before income tax 1,498,959 432,550 307,450 651,947 — 2,890,906 Expenditures for segment assets 1,749,509 604,669 275,940 52,563 — 2,682,681 December 31, 2021 Investments accounted for using the equity method 459,436 68,362 84,913 — — 612,711 Contract assets 170,698 31,436 — — — 202,134 Note 1: Inter-group revenues were eliminated upon consolidation. Note 2: The disaggregated product and service type from the Group’s contract with customer is the same as those disclosed in above reportable segment. b. Revenue from major products and services For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Packaging service $ 198,916,897 $ 218,666,071 $ 272,543,899 $ 9,824,942 Testing service 42,658,686 47,271,074 49,978,736 1,801,685 EMS 165,789,479 204,690,669 239,488,267 8,633,319 Others 5,817,122 6,350,896 7,986,231 287,896 $ 413,182,184 $ 476,978,710 $ 569,997,133 $ 20,547,842 c. Geographical information The Group’s revenue from external customers by location of headquarter and information about its non-current 1) Net revenues from external customers For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) United States $ 245,521,027 $ 297,117,001 $ 353,500,361 $ 12,743,344 Taiwan 51,244,470 64,829,301 94,598,067 3,410,168 Asia 75,938,364 74,447,091 62,523,167 2,253,900 Europe 38,613,132 39,477,306 57,910,641 2,087,622 Others 1,865,191 1,108,011 1,464,897 52,808 $ 413,182,184 $ 476,978,710 $ 569,997,133 $ 20,547,842 2) Non-current assets December 31 2020 (Retrospectively Adjusted) 2021 NT$ NT$ US$ (Note 4) Taiwan $ 239,353,978 $ 252,525,376 $ 9,103,294 China 66,253,694 65,375,423 2,356,720 Others 31,875,938 34,702,992 1,251,009 $ 337,483,610 $ 352,603,791 $ 12,711,023 Non-current d. Major customers Except customer A from which the operating revenues generated from packaging and EMS segments were NT$103,987,781 NT$145,952,908 thousand and NT$158,624,032 thousand (US$5,718,242 thousand) for the years ended December 31, 2019, 2020 and 2021, respectively, and customer B from which the operating revenues generated from packaging and testing segments was NT$44,653,072 thousand for the year ended December 31, 2019, the Group did not have any other individual customer from which the operating revenues exceeded 10% of operating revenues for the years ended December 31, 2019, 2020 and 2021.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Statement of Compliance	a. Statement of compliance The consolidated financial statements have been prepared in accordance with IFRSs as issued by the IASB.
Basis of Preparation	b. Basis of preparation The consolidated financial statements have been prepared on the historical cost basis except for financial instruments measured at fair value and net defined benefit liabilities which are measured at the present value of the defined benefit obligation less the fair value of plan assets. The fair value measurements, which are grouped into Levels 1 to 3 based on the degree to which the fair value measurement inputs are observable and based on the significance of the inputs to the fair value measurement in its entirety, are described as follows: 1) Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities; 2) Level 2 inputs are inputs other than quoted prices included within Level 1 that are observable for an asset or a liability, either directly (i.e. as prices) or indirectly (i.e. derived from prices); and 3) Level 3 inputs are unobservable inputs for an asset or a liability.
Classification of Current and Non-current Assets and Liabilities	c. Classification of current and non-current Current assets include cash and cash equivalents and those assets held primarily for trading purposes or expected to be realized within twelve months after the balance sheet date, unless the asset is to be used for an exchange or to settle a liability, or otherwise remains restricted, at more than twelve months after the balance sheet date. Current liabilities are obligations incurred for trading purposes or to be settled within twelve months after the balance sheet date (even if an agreement to refinance, or to reschedule payments, on a long-term basis is completed after the balance sheet date and before the consolidated financial statements are authorized for issue) and liabilities that do not have an unconditional right to defer settlement for at least 12 months after the balance sheet date (terms of a liability that could, at the option of the counterparty, result in its settlement by the issue of equity instruments do not affect its classification). Assets and liabilities that are not classified as current are classified as non-current. The Group engages in the construction business which has an operating cycle of over one year. The normal operating cycle applies when considering the classification of the Group’s construction-related assets and liabilities.
Basis of Consolidation	d. Basis of consolidation 1) Principles for preparing consolidated financial statements The consolidated financial statements incorporate the financial statements of the Company and the entities controlled by the Company (i.e. its subsidiaries). Income and expenses of subsidiaries acquired or disposed of during the period are included in the consolidated statement of profit or loss and other comprehensive income from the effective dates of acquisitions up to the effective dates of disposals, as appropriate. When necessary, adjustments are made to the financial statements of subsidiaries to bring their accounting policies into line with those used by the Company. All intra-group transactions, balances, income and expenses are eliminated in full upon consolidation. Total comprehensive income of subsidiaries is attributed to the owners of the Company and to the non-controlling non-controlling Changes in the Group’s ownership interests in subsidiaries that do not result in the Group losing control over the subsidiaries are accounted for as equity transactions. The carrying amounts of the interests of the Group and the non-controlling non-controlling When the Group loses control of a subsidiary, a gain or loss is recognized in profit or loss and is calculated as the difference between (i) the aggregate of the fair value of the consideration received and any investment retained in the former subsidiary at its fair value at the date when control is lost and (ii) the assets (including any goodwill) and liabilities and any non-controlling 2) Subsidiaries included in consolidated financial statements were as follows: Establishment and Operating Percentage of Ownership (%) December 31 Name of Investor Name of Investee Main Businesses Location 2020 2021 The Company ASE Engaged in the packaging and testing of semiconductors R.O.C. 100.0 100.0 USI Inc. (“USIINC”) Holding company R.O.C. 100.0 100.0 SPIL Engaged in the assembly, testing and turnkey services of integrated circuit R.O.C. 100.0 100.0 ASE A.S.E. Holding Limited Holding company Bermuda 100.0 100.0 J & R Holding Limited (“J&R Holding”) Holding company Bermuda 100.0 100.0 Innosource Limited Holding company British Virgin Islands 100.0 100.0 Omniquest Industrial Limited Holding company British Virgin Islands 71.0 71.0 ASE Marketing & Service Japan Co., Ltd. Engaged in marketing and sales services Japan 100.0 100.0 ASE Test, Inc. Engaged in the testing of semiconductors R.O.C. 100.0 100.0 Luchu Development Corporation Engaged in the development of real estate properties R.O.C. 67.1 67.1 Advanced Microelectronic Products Inc. (“AMPI”) Engaged in the manufacturing of integrated circuit R.O.C. 7.6 7.6 ASE Test, Inc. Alto Enterprises Limited Holding company British Virgin Islands 100.0 100.0 Super Zone Holdings Limited Holding company Hong Kong 100.0 100.0 Luchu Development Corporation Engaged in the development of real estate properties R.O.C. 19.0 19.0 TLJ Intertech Inc. Engaged in information software services R.O.C. 60.0 60.0 MingFeng Information Service Corp., Ltd. In the process of liquidation (Liquidation completed in February 2022) R.O.C. 100.0 100.0 AMPI Engaged in the manufacturing of integrated circuit R.O.C. 43.4 43.4 A.S.E. Holding Limited ASE Investment (Labuan) Inc. Holding company Malaysia 70.1 70.1 ASE Test Limited (“ASE Test”) Holding company Singapore 10.2 10.2 ASE Technology Partners, Limited Holding company and was established in August 2021 British Cayman Islands — 100.0 Integrated Solutions Enterprise Europe Trading company, and was acquired in October 2021 (Note 29) Belgium — 100.0 J&R Holding ASE Test Holding company Singapore 89.8 89.8 Omniquest Industrial Limited Holding company British Virgin Islands 8.4 8.4 J&R Industrial Inc. Engaged in leasing equipment and investing activity R.O.C. 100.0 100.0 ASE Japan Co., Ltd. Engaged in the packaging and testing of semiconductors Japan 100.0 100.0 ASE (U.S.) Inc. After-sales service and sales support U.S.A. 100.0 100.0 Global Advanced Packaging Technology Limited Holding company British Cayman Islands 100.0 100.0 Anstock Limited Liquidated in June 2021 British Cayman Islands 100.0 — Anstock II Limited Liquidated in June 2021 British Cayman Islands 100.0 — Suzhou ASEN Semiconductors Co., Ltd. (“ASEN”) Engaged in the packaging and testing of semiconductors (organizational adjustment through exchanged shares to Global Advanced Packaging Test (Hong Kong) Limited in September 2021) Suzhou, China 100.0 — Innosource Limited Omniquest Industrial Limited Holding company British Virgin Islands 20.6 20.6 ASE (Shanghai) Inc. Engaged in the production of substrates Shanghai, China 8.5 8.5 Omniquest Industrial Limited ASE Corporation Holding company British Cayman Islands 100.0 100.0 Alto Enterprises Limited ASE (Kunshan) Inc. Engaged in the packaging and testing of semiconductors Kun Shan, China 22.9 (Note 2 ) ASE Investment (Kun Shan) Limited Holding company Kun Shan, China 85.9 85.9 Super Zone Holdings Limited Advanced Semiconductor Engineering (China) Ltd. Engaged in the packaging and testing of semiconductors, after-sale services, advisory and lease of factory Shanghai, China 100.0 100.0 ASE Investment (Labuan) Inc. ASE (Korea) Inc. (“ASE Korea”) Engaged in the packaging and testing of semiconductors Korea 100.0 100.0 ASE Technology Partners, Limited ASE Technology Acquisition Corporation Holding company and was established in August 2021 British Cayman Islands — 100.0 ASE Korea ASE (Weihai) Inc. Engaged in the packaging and testing of semiconductors (disposed to J&R Holding and organizational adjustment through exchanged shares from J&R Holding to GAPT (Hong Kong) Limited in October 2021) Shandong, China 100.0 — ASE Test ASE Test Holdings, Ltd. Holding company British Cayman Islands 100.0 100.0 ASE Holdings (Singapore) Pte Ltd Holding company Singapore 100.0 100.0 ASE Investment (Labuan) Inc. Holding company Malaysia 29.9 29.9 ASE Singapore Pte. Ltd. Engaged in the packaging and testing of semiconductors Singapore 100.0 100.0 ASE Test Holdings, Ltd. ISE Labs, Inc. Engaged in the testing of semiconductors U.S.A. 100.0 100.0 Establishment and Operating Percentage of Ownership (%) December 31 Name of Investor Name of Investee Main Businesses Location 2020 2021 ISE Labs, Inc. ISE Services, Inc. Engaged in wafer procurement and customer product management services U.S.A. 100.0 100.0 ASE Holdings (Singapore) Pte Ltd ASE Electronics (M) Sdn. Bhd. Engaged in the packaging and testing of semiconductors Malaysia 100.0 100.0 Global Advanced Packaging Technology Limited ASE Assembly & Test (Shanghai) Limited Engaged in the packaging and testing of semiconductors and leasing of properties Shanghai, China 100.0 100.0 ASE Advanced Semiconductor (Shanghai) Limited Engaged in the packaging and testing of semiconductors (disposed to ASEN in November 2021) Shanghai, China 100.0 — GAPT Holding Limited Holding company and was established in August 2021 British Virgin Islands — (Note 2 ) GAPT Holding Limited Global Advanced Packaging Test (Hongkong) Limited Engaged in the trading of substrates and was established in August 2021 Hong Kong — (Note 2 ) Global Advanced Packaging Test (Hongkong) Limited Suzhou ASEN Semiconductors Co., Ltd. (“ASEN”) Engaged in the packaging and testing of semiconductors (acquired from J&R Holding in September 2021 ) Suzhou, China — (Note 2 ) ASE (Weihai) Inc. Engaged in the packaging and testing of semiconductors (acquired from J&R Holding in October 2021 through share exchange under restructure ) Shandong, China — (Note 2 ) ASEN ASE Advanced Semiconductor (Shanghai) Limited Engaged in the packaging and testing of semiconductors (acquired from Global Advanced Packaging Technology Limited in November 2021) Shanghai, China — (Note 2 ) ASE Assembly & Test (Shanghai) Limited ASE Investment (Kun Shan) Limited Holding company Kun Shan, China 14.1 14.1 Wuxi Tongzhi Microelectronics Co., Ltd. Engaged in the packaging and testing of semiconductors Wuxi, China 100.0 100.0 ISE Labs, China, Ltd. Engaged in the testing of semiconductor Shanghai, China 100.0 100.0 Shanghai Ding Hui Real Estate Development Co., Ltd. (“DH”) Engaged in the development, construction and sale of real estate properties Shanghai, China 60.0 60.0 DH Shanghai Ding Qi Property Management Co., Ltd. Engaged in the management of real estate properties Shanghai, China 100.0 100.0 Shanghai Ding Wei Real Estate Development Co., Ltd. (“DW”) Engaged in the development, construction and leasing of real estate properties Shanghai, China 100.0 100.0 Shanghai Ding Yu Real Estate Development Co., Ltd. Engaged in the development, construction and leasing of real estate properties Shanghai, China 100.0 100.0 Kun Shan Ding Hong Real Estate Development Co., Ltd Engaged in the development, construction and leasing of real estate properties Kun Shan, China 100.0 100.0 Shanghai Ding Xu Property Management Co., Ltd. Engaged in the management of real estate properties Shanghai, China 100.0 100.0 Shanghai Dingyao Estate Development Co., Ltd. Engaged in the management of real estate properties Shanghai, China 100.0 100.0 Shanghai Ding Fan Business Management Co., Ltd. Engaged in the management of real estate properties (acquired from DW in November 2020) Shanghai, China 100.0 100.0 ASE Investment (Kun Shan) Limited ASE (Kun s Engaged in the packaging and testing of semiconductors Kun Shan, China 49.3 (Note 2 ) ASE Corporation ASE Mauritius Inc. Holding company Mauritius 100.0 100.0 ASE Labuan Inc. Holding company Malaysia 100.0 100.0 ASE Mauritius Inc. ASE (Kunshan) Inc. Engaged in the packaging and testing of semiconductors Kun Shan, China 27.8 (Note 2 ) ASE (Shanghai) Inc. Engaged in the production of substrates Shanghai, China 91.5 91.5 ASE Labuan Inc. ASE Electronics Inc. Engaged in the production of substrates R.O.C. 100.0 100.0 ASE (Shanghai) Inc. Advanced Semiconductor Engineering (HK) Limited Engaged in the trading of substrates Hong Kong 100.0 100.0 Shanghai Ding Hui Real Estate Development Co., Ltd. Engaged in the development, construction and sale of real estate properties Shanghai, China 40.0 40.0 Universal Scientific Industrial (Shanghai) Co., Ltd. (“USISH”) Engaged in the designing, manufacturing and sales of electronic components Shanghai, China 0.8 0.8 USIINC Huntington Holdings International Co., Ltd. Holding company British Virgin Islands 100.0 100.0 Huntington Holdings International Co., Ltd. Unitech Holdings International Co., Ltd. Holding company British Virgin Islands 100.0 100.0 Real Tech Holdings Limited Holding company British Virgin Islands 100.0 100.0 Universal ABIT Holding Co., Ltd. In the process of liquidation British Cayman Islands 100.0 100.0 Real Tech Holdings Limited USI Enterprise Limited (“USIE”) Engaged in the service of investment advisory and warehousing management Hong Kong 95.9 100.0 USIE USISH Engaged in the designing, manufacturing and sales of electronic components Shanghai, China 76.6 77.1 USISH Universal Global Technology Co., Limited Holding company Hong Kong 100.0 100.0 Establishment and Operating Percentage of Ownership (%) December 31 Name of Investor Name of Investee Main Businesses Location 2020 2021 Universal Global Technology (Kunshan) Co., Ltd. (“UGKS”) Engaged in the designing and manufacturing of electronic components Kun Shan, China 100.0 100.0 Universal Global Technology (Shanghai) Co., Ltd. Engaged in the processing and sales of computer and communication peripherals as well as business in import and export of goods and technology Shanghai, China 100.0 100.0 Universal Global Electronics (Shanghai) Co., Ltd. Engaged in the sales of electronic components and telecommunications equipment Shanghai, China 100.0 100.0 USI Electronics (Shenzhen) Co., Ltd. Engaged in the design, manufacturing and sales of motherboards and computer peripherals Shenzhen, China 50.0 50.0 Universal Global Technology (Huizhou) Co., Ltd. Engaged in the research and manufacturing of new electronic applications, communications, computers and other electronics products and also provided auxiliary technical services as well as import and export services Huizhou, China 100.0 100.0 FINANCIERE AFG (“FAFG”) Holding company France 10.4 10.4 Universal Global Technology Co., Limited Universal Global Industrial Co., Limited Engaged in manufacturing, trading and investing activity Hong Kong 100.0 100.0 Universal Global Scientific Industrial Co., Ltd. (“UGTW”) Engaged in the manufacturing of components of telecommunication and cars and provision of related R&D services R.O.C. 100.0 100.0 USI America Inc. Engaged in the manufacturing and processing of motherboards and wireless network communication and provision of related technical service U.S.A. 100.0 100.0 Universal Scientific Industrial De Mexico S.A. De C.V. Engaged in the assembling of motherboards and computer components Mexico 100.0 100.0 USI Japan Co., Ltd. Engaged in the manufacturing and sales of computer peripherals, integrated chip and other related accessories Japan 100.0 100.0 USI Electronics (Shenzhen) Co., Ltd. Engaged in the design, manufacturing and sales of motherboards and computer peripherals Shenzhen, China 50.0 50.0 Universal Global Electronics Co., Ltd. Engaged in accepting and outsourcing orders as well as sales of electronic components and service of technical advisory Hong Kong 100.0 100.0 Universal Scientific Industrial (France) (“USIFR”) Engaged in investing activities France 100.0 100.0 UNIVERSAL INDUSTRIA L TNAM CO ., Engaged in IC assembly for wearable devices and was established in July 2020. Vietnam 100.0 100.0 Universal Global Industrial Co., Limited Universal Scientific Industrial De Mexico S.A. De C.V. Engaged in the assembling of motherboards and computer components Mexico (Note 1 ) (Note 1 ) UGTW Universal Scientific Industrial Co., Ltd. (“USI”) Engaged in the manufacturing, processing and sales of computers, computer peripherals and related accessories R.O.C. 100.0 100.0 Universal Global Electronics Co., Ltd. Universal Scientific Industrial Poland Sp. z o.o. (“USIPL”) Engaged in the design and manufacturing of electronic components and new electronic applications. Poland 100.0 100.0 Universal Global Electronics (Shanghai) Co., Ltd. USI Science and Technology (Shenzhen) Co., Ltd. Engaged in the design of electronic components, service of technical advisory; wholesale of electronic components and communication peripherals as well as business in import and export of goods and management of properties. Established in November 2020. Shenzhen, China 100.0 100.0 USIFR FAFG Holding company France 89.6 89.6 ASTEELFLASH GROUP Holding company (disposed to FAFG in October 2021) France (Note 1 ) — Establishment and Operating Percentage of Ownership (%) December 31 Name of Investor Name of Investee Main Businesses Location 2020 2021 FAFG ASTEELFLASH GROUP Holding company (acquired 1 share from Universal Scientific Industrial (France) in October 2021) France 100.0 100.0 MANUFACTURING POWER TUNISIA Engaged in the design and manufacturing of electronic components Tunisia 0.1 0.1 ASTEELFLASH MEXICO S.A. de C.V. Engaged in the design and manufacturing of electronic components Mexico 0.1 0.1 ASTEELFLASH GROUP ASTEELFLASH (BEDFORD) LIMITED Engaged in the design and manufacturing of electronic components United Kingdom 100.0 100.0 ASTEELFLASH FRANCE Engaged in the design and manufacturing of electronic components France 99.9 99.9 ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia 100.0 100.0 ASTEELFLASH HONG KONG LIMITED Holding company Hong Kong 100.0 100.0 ASTEELFLASH MEXICO S.A. de C.V. Engaged in the design and manufacturing of electronic components Mexico 99.9 99.9 ASTEELFLASH GERMANY GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 MANUFACTURING POWER TUNISIA Engaged in the design and manufacturing of electronic components Tunisia 99.9 99.9 ASTEELFLASH US HOLDING CORP. Holding company U.S.A. 100.0 100.0 ASTEEL ELECTRONIQUE FOUCHANA Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH TUNISIE S.A. in June 2021) Tunisia (Note 1 ) — AFERH TUNISIE Engaged in the management, training and consulting of human resources Tunisia 0.5 0.5 ASTEEL ELECTRONICS MANUFACTURING SERVICES Engaged in the design and manufacturing of electronic components Tunisia 0.1 0.1 ASTEELFLASH PLZEN S.R.O. Engaged in the design and manufacturing of electronic components (acquired from ASTEELFLASH GERMANY GmbH in April 2021) Czech Republic — 100.0 ASTEELFLASH (BEDFORD) LIMITED ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1 ) (Note 1 ) ASTEELFLASH TECHNOLOGIE ASTEELFLASH FRANCE Engaged in the design and manufacturing of electronic components France (Note 1 ) (Note 1 ) ASTEELFLASH FRANCE SCI CHASSET Engaged in the management and operation of real estate properties and holding the ownership of real estate properties (Liquidated in July 2021) France 100.0 — AFERH Engaged in the management, training and consulting of human resources (Liquidated in July 2021) France 100.0 — ASTEEL ELECTRONICS MANUFACTURING SERVICES Engaged in the design and manufacturing of electronic components Tunisia 99.9 99.9 ASTEEL ELECTRONIQUE FOUCHANA Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH TUNISIE S.A. in June 2021) Tunisia 94.2 — ASTEELFLASH TECHNOLOGIE Engaged in projection of plastic and the design and manufacturing of industrial components France 100.0 100.0 ASTEELFLASH BRETAGNE Engaged in the design and manufacturing of electronic components France 100.0 100.0 ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1 ) (Note 1 ) ASTEELFLASH TUNISIE S.A. ASTEEL ELECTRONIQUE TUNISIE Engaged in the design and manufacturing of electronic components (merged by ASTEELFLASH TUNISIE S.A.in December 2021) Tunisia 100.0 — ASTEEL ELECTRONIQUE FOUCHANA Engaged in the design and manufacturing of electronic components (acquired from ASTEELFLASH GROUP, ASTEELFLASH FRANCE, Asteelflash Suzhou Co., Ltd. and ASTEELFLASH USA CORP.in June 2021 and merged by ASTEELFLASH TUNISIE S.A. in December 2021) Tunisia (Note 1 ) — AFERH AFERH TUNISIE Engaged in the management, training and consulting of organization and human resources Tunisia 99.5 99.5 ASTEELFLASH HONG KONG LIMITED Asteelflash S ou Co., Ltd . Engaged in the design and manufacturing of electronic components Suzhou, China 100.0 100.0 Asteelflash Suzhou Co., Ltd. A STE EL ELECT R ONIQUE FO UCHANA Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH TUNISIE S.A. in June 2021) Tunisia (Note 1 ) — ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1 ) (Note 1 ) ASTEELFLASH GERMANY GmbH ASTEELFLASH HERSFELD GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 ASTEELFLASH EBERBACH GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 Establishment and Operating Percentage of Ownership (%) December 31 Name of Investor Name of Investee Main Businesses Location 2020 2021 ASTEELFLASH BONN GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 ASTEELFLASH SCHWANDORF GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 ASTEELFLASH PLZEN S.R.O. Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH GROUP in April 2021) Czech Republic 100.0 — ASTEELFLASH DESIGN SOLUTIONS HAMBOURG GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 EN ELECTRONICNETWORK SRL Engaged in the design and manufacturing of electronic components Romania 100.0 100.0 ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1) (Note 1 ) ASTEELFLASH MEXICO S.A. de C.V. ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1) (Note 1 ) ASTEELFLASH US HOLDING CORP. ASTEELFLASH USA CORP. Engaged in the design and manufacturing of electronic components U.S.A. 100.0 100.0 ASTEELFLASH USA CORP. ASTEEL ELECTRONIQUE FOUCHANA Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH TUNISIE S.A. in June 2021) Tunisia (Note 1) — ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1) (Note 1 ) SPIL SPIL (B.V.I.) Holding Limited Engaged in investing activities British Virgin Islands 100.0 100.0 Siliconware Investment Co., Ltd. Engaged in investing activities R.O.C. 100.0 100.0 SPIL (B.V.I.) Holding Limited Siliconware USA, Inc. Engaged in marketing activities U.S.A. 100.0 100.0 SPIL (Cayman) Holding Limited Engaged in investing activities British Cayman Islands 100.0 100.0 SPIL (Cayman) Holding Limited Siliconware Technology (Suzhou) Limited (“SZ”) Engaged in the packaging and testing of semiconductors Suzhou, China 100.0 100.0 Note 1: The number of shares held was 1 share or 3 shares and the percentage of ownership was less than 0.1%. Note 2: In December 2021, the Company’s board of directors resolved to dispose its 100% shareholdings in those subsidiaries, which were settled in December 2021 and resulted in losing its control over those subsidiaries. Refer to Note 30 DISPOSAL OF SUBSIDIARIES for related disclosure.
Business Combinations	e. Business combinations Acquisitions of businesses are accounted for using the acquisition method. Acquisition-related costs are generally recognized in profit or loss as they are incurred. Goodwill is measured as the excess of the sum of the consideration transferred, the amount of any non-controlling re-assessment, non-controlling Where the consideration the Group transfers in a business combination includes assets or liabilities resulting from a contingent consideration arrangement, the contingent consideration is measured at its acquisition-date fair value and considered as part of the consideration transferred in a business combination. Changes in the fair value of the contingent consideration that qualify as measurement period adjustments are adjusted retrospectively, with the corresponding adjustments being made against goodwill or gains on bargain purchases. Measurement period adjustments are adjustments that arise from additional information obtained during the measurement period about facts and circumstances that existed as of the acquisition date. The measurement period does not exceed 1 year from the acquisition date. The subsequent accounting for changes in the fair value of the contingent consideration that do not qualify as measurement period adjustments depends on how the contingent consideration is classified. Contingent consideration not classified as equity is remeasured at fair value at the end of subsequent reporting period with any gain or loss recognized in profit or loss. When a business combination is achieved in stages, the Group’s previously held equity interest in an acquiree is remeasured to fair value at acquisition date, and the resulting gain or loss, if any, is recognized in profit or loss or other comprehensive income. Amounts arising from interests in the acquiree prior to the acquisition date that have previously been recognized in other comprehensive income are recognized on the same basis as would be required had those interest been directly disposed of by the Group. If the initial accounting for a business combination is incomplete by the end of the reporting period in which the combination occurs, the Group reports provisional amounts for the items for which the accounting is incomplete. Those provisional amounts are adjusted retrospectively during the measurement period, or additional assets or liabilities are recognized, to reflect new information obtained about facts and circumstances that existed at the acquisition date that, if known, would have affected the amounts recognized at that date. Business combination involving entities under common control is not accounted for using the acquisition method but is accounted for at the carrying amounts of the entities. The Group elected not to restate comparative information of the prior period in the financial statements as the business combination was an organization restructure under common control.
Foreign Currencies	f. Foreign currencies In preparing the financial statements of each individual entity, transactions in currencies other than the entity’s functional currency (i.e. foreign currencies) are recognized at the rates of exchange prevailing at the dates of the transactions. At each balance sheet date, monetary items denominated in foreign currencies are retranslated at the rates prevailing at that date. Exchange differences on monetary items arising from settlement or translation are recognized in profit or loss in the period in which they arise except for exchange differences on transactions entered into in order to hedge certain foreign currency risks. Non-monetary non-monetary non-monetary Non-monetary For the purposes of presenting the consolidated financial statements, the assets and liabilities of the Group’s foreign operations (including subsidiaries, associates and joint ventures in other countries that use currencies which are different from the currency of the Company) are translated into the New Taiwan dollars using exchange rates prevailing at each balance sheet date. Income and expense items are translated at the average exchange rates for the period. The resulting currency translation differences are recognized in other comprehensive income and accumulated in equity attributed to the owners of the Company and non-controlling On the disposal of the Group’s entire interest in a foreign operation, or a disposal involving the loss of control over a subsidiary that includes a foreign operation, or a partial disposal of an interest in a joint arrangement or an associate that includes a foreign operation of which the retained interest becomes a financial asset, all of the exchange differences accumulated in equity in respect of that operation attributable to the owners of the Company are reclassified to profit or loss. In relation to a partial disposal of a subsidiary that does not result in the Group losing control over the subsidiary, the proportionate share of accumulated exchange differences is re-attributed non-controlling Goodwill and fair value adjustments recognized on identifiable assets and liabilities of acquired foreign operation are treated as assets and liabilities of the foreign operation and translated at the rates of exchange prevailing at the end of each reporting period. Exchange differences are recognized in other comprehensive income.
Inventories and Inventories Related to Real Estate Business	g. Inventories and inventories related to real estate business Inventories, including raw materials, supplies, work in process, finished goods, and materials and supplies in transit are stated at the lower of cost or net realizable value. Inventory write-downs are made by item, except for those that may be appropriate to group items of similar or related inventories. Net realizable value is the estimated selling prices of inventories less all estimated costs of completion and estimated costs necessary to make the sale. Raw materials and supplies are recorded at moving average cost while work in process and finished goods are recorded at standard cost. Inventories related to real estate business include land and buildings held for sale, land held for construction and construction in progress. Land held for development is recorded as land held for construction upon obtaining the title of ownership. Prior to the completion, the borrowing costs directly attributable to construction in progress are capitalized as part of the cost of the asset. Construction in progress is transferred to land and buildings held for sale upon completion. Land and buildings held for sale, construction in progress and land held for construction are stated at the lower of cost or net realizable value and related write-downs are made by item. The amounts received in advance for real estate properties are first recorded as advance receipts and then recognized as revenue when the construction is completed and the title and significant risk of the real estate properties are transferred to customers. Cost of sales of land and buildings held for sale are recognized based on the ratio of property sold to the total property developed.
Investments in associates and joint ventures	h. Investments in associates and joint ventures An associate is an entity over which the Group has significant influence and that is neither a subsidiary nor an interest in a joint venture. Joint venture is a joint arrangement whereby the Group and other parties that have joint control of the arrangement have rights to the net assets of the arrangement. The Group applies the equity method to investments in an associate and joint venture. Under the equity method, investments in an associate and a joint venture are initially recognized at cost and adjusted thereafter to recognize the Group’s share of the profit or loss and other comprehensive income of the associate and joint venture. The Group also recognizes the changes in the Group’s share of equity of associates and joint venture. Any excess of the cost of acquisition over the Group’s share of the net fair value of the identifiable assets and liabilities of an associate or a joint venture at the date of acquisition is recognized as goodwill, which is included within the carrying amount of the investment and is not amortized. Any excess of the Group’s share of the net fair value of the identifiable assets and liabilities over the cost of acquisition after reassessment is recognized immediately in profit or loss. When the Group subscribes for additional new shares of an associate and joint venture at a percentage different from its existing ownership percentage, the resulting carrying amount of the investment differs from the amount of the Group’s proportionate interest in the associate and joint venture. The Group records such a difference as an adjustment to investments with the corresponding amount charged to gain or loss on disposal of investments accounted for using the equity method. When the Group reduces its ownership interest in an associate or a joint venture but the Group continues to use the equity method, the Group reclassifies to profit or loss the proportion of the gain or loss that had previously been recognised in other comprehensive income relating to that reduction in ownership interest if that gain or loss would be reclassified to profit or loss on the disposal of the related assets or liabilities. When the Group’s share of losses of an associate and a joint venture equals or exceeds its interest in that associate and joint venture (which includes any carrying amount of the investment accounted for using the equity method and long-term interests that, in substance, form part of the Group’s net investment in the associate and joint venture), the Group discontinues recognizing its share of further losses. Additional losses and liabilities are recognized only to the extent that the Group has incurred legal obligations or constructive obligations, or made payments on behalf of that associate and joint venture. The entire carrying amount of an investment (including goodwill) is tested for impairment as a single asset by comparing its recoverable amount with its carrying amount. Any impairment loss recognized is not allocated to any asset, including goodwill, that forms part of the carrying amount of the investment. Any reversal of that impairment loss is recognized to the extent that the recoverable amount of the investment subsequently increases. The Group discontinues the use of the equity method from the date on which its investment ceases to be an associate and a joint venture. Any retained investment is measured at fair value at that date, and the fair value is regarded as the investment’s fair value on initial recognition as a financial asset. The difference between the previous carrying amount of the associate and the joint venture attributable to the retained interest and its fair value is included in the determination of the gain or loss on disposal of the associate and the joint venture. The Group accounts for all amounts previously recognized in other comprehensive income in relation to that associate and joint venture on the same basis as would be required had that associate directly disposed of the related assets or liabilities. If an investment in an associate becomes an investment in a joint venture or an investment in a joint venture becomes an investment in an associate, the Group continues to apply the equity method and does not remeasure the retained interest. When a group entity transacts with its associate and joint venture, profits and losses resulting from the transactions with the associate and joint venture are recognized in the Group’ consolidated financial statements only to the extent that interests in the associate and the joint venture are not related to the Group.
Property, Plant and Equipment	i. Property, plant and equipment Except for land which is stated at cost, property, plant and equipment are stated at cost less accumulated depreciation and accumulated impairment. Properties in the course of construction are carried at cost, less any recognized impairment loss. Cost includes professional fees and borrowing costs eligible for capitalization. Such assets are depreciated and classified to the appropriate categories of property, plant and equipment when completed and ready for their intended use. Freehold land is not depreciated. Depreciation of property, plant and equipment is recognized using the straight-line method. Each significant part is depreciated separately. The estimated useful lives, residual values and depreciation method are reviewed at each balance sheet date, with the effect of any changes in estimate accounted for on a prospective basis. On derecognition of an item of property, plant and equipment, the difference between the sales proceeds and the carrying amount of the asset is recognized in profit or loss.
Investment Properties	j. Investment properties Investment properties are properties held to earn rental and/or for capital appreciation. Investment properties include right-of-use Freehold investment properties are initially measured at cost, including transaction costs. Subsequent to initial recognition, investment properties are measured at cost less accumulated depreciation and accumulated impairment loss. Investment properties acquired through leases are initially measured at cost, which comprises the initial measurement of lease liabilities adjusted for lease payments made on or before the commencement date, plus initial direct costs incurred and an estimate of costs needed to restore the underlying assets, less any lease incentives received. These investment properties are subsequently measured at cost less accumulated depreciation and accumulated impairment loss and adjusted for any remeasurement of the lease liabilities. Depreciation is recognized using the straight-line method. Investment properties under construction are measured at cost less accumulated impairment loss. Cost includes professional fees and borrowing costs eligible for capitalization. Depreciation of these assets commences when the assets are ready for their intended use. For a transfer of classification from investment properties to property, plant and equipment and to right-of-use For a transfer of classification from property, plant and equipment and right-of-use For a transfer of classification from inventories to investment properties, the deemed cost of an item of property for subsequent accounting is its carrying amount at the inception of an operating lease. On derecognition of an investment property, the difference between the net disposal proceeds and the carrying amount of the asset is included in profit or loss.
Goodwill	k. Goodwill Goodwill arising from an acquisition of a business is carried at cost as established at the date of acquisition of the business less accumulated impairment loss. For the purposes of impairment testing, goodwill is allocated to each of the Group’s cash-generating units or groups of cash-generating units (referred to as “cash-generating unit”) that is expected to benefit from the synergies of the combination. A cash-generating unit to which goodwill has been allocated is tested for impairment annually, or more frequently when there is an indication that the unit may be impaired, by comparing its carrying amount, including the attributed goodwill, with its recoverable amount. However, if the goodwill allocated to a cash-generating unit was acquired in a business combination during the current annual period, that unit shall be tested for impairment before the end of the current annual period. If the recoverable amount of the cash-generating unit is less than its carrying amount, the impairment loss is allocated first to reduce the carrying amount of any goodwill allocated to the unit and then pro rata to the other assets of the unit based on the carrying amount of each asset in the unit. Any impairment loss is recognized directly in profit or loss. An impairment loss recognized for goodwill is not reversed in subsequent periods.
Other Intangible Assets	l. Other intangible assets 1) Separate acquisition Other intangible assets with finite useful lives acquired separately are initially measured at cost and subsequently measured at cost less accumulated amortization and accumulated impairment loss. Other intangible assets are amortized using the straight-line method over their estimated useful lives. The estimated useful lives, residual values, and amortization methods are reviewed at each balance sheet date, with the effect of any changes in estimate being accounted for on a prospective basis. 2) Acquired through business combinations Other intangible assets acquired in a business combination and recognized separately from goodwill are initially recognized at their fair value at the acquisition date which is regarded as their cost. Subsequent to initial recognition, they are measured on the same basis as intangible assets that are acquired separately. 3) Derecognition On derecognition of an intangible asset, the difference between the net disposal proceeds and the carrying amount of the asset are recognized in profit or loss.
Impairment of Tangible and Intangible Assets Other than Goodwill	m. Impairment of property, plant and equipment, right-of-use At each balance sheet date or whenever events or changes in circumstances indicate that the carrying value may not be recoverable, the Group reviews the carrying amounts of its property, plant and equipment, right-of-use When an impairment loss is subsequently reversed, the carrying amount of the asset or cash-generating unit is increased to the revised estimate of its recoverable amount, but only to the extent of the carrying amount that would have been determined had no impairment loss been recognized for the asset or cash-generating unit in prior years. A reversal of an impairment loss is recognized immediately in profit or loss.
Financial Instruments	n. Financial instruments Financial assets and financial liabilities are recognized when a group entity becomes a party to the contractual provisions of the instruments. Financial assets and financial liabilities are initially measured at fair value. Transaction costs that are directly attributable to the acquisition or issue of financial assets and financial liabilities (other than financial assets and financial liabilities at FVTPL) are added to or deducted from the fair value of the financial assets or financial liabilities, as appropriate, on initial recognition. Transaction costs directly attributable to the acquisition of financial assets or financial liabilities at fair value through profit or loss are recognized immediately in profit or loss. 1) Financial assets All regular way purchases or sales of financial assets are recognized and derecognized on a settlement date basis. a) Measurement categories Financial assets held by the Group are classified into the following categories: financial assets at FVTPL, financial assets at amortized cost and investments in debt instruments and equity instruments at FVTOCI. i. Financial asset at FVTPL Financial asset is classified as at FVTPL when the financial asset is mandatorily classified or it is designated as at FVTPL. The Group’s financial assets mandatorily classified as at FVTPL include investments in equity instruments which are not designated as at FVTOCI and debt instruments that do not meet the amortized cost criteria or the FVTOCI criteria. Financial assets at FVTPL are subsequently measured at fair value, and any dividends or interest earned on such financial assets are recognized in other income; any remeasurement gains or losses on such financial assets are recognized in other gains or losses. Fair value is determined in the manner described in Note 34. ii. Financial assets at amortized cost Financial assets that meet the following conditions are subsequently measured at amortized cost: i) The financial asset is held within a business model whose objective is to hold financial assets in order to collect contractual cash flows; and ii) The contractual terms of the financial asset give rise on specified dates to cash flows that are solely payments of principal and interest on the principal amount outstanding. Subsequent to initial recognition, financial assets at amortized cost, including cash and cash equivalents, trade receivables at amortized cost, other receivables and other financial assets, are measured at amortized cost, which equals to gross carrying amount determined using the effective interest method less any impairment loss. Exchange differences are recognized in profit or loss. Interest income is calculated by applying the effective interest rate to the gross carrying amount of a financial asset, except for: i) Purchased or originated credit-impaired financial assets, for which interest income is calculated by applying the credit-adjusted effective interest rate to the amortized cost of the financial asset; and ii) Financial assets that are not credit-impaired on purchase or origination but have subsequently become credit-impaired, for which interest income is calculated by applying the effective interest rate to the amortized cost of such financial assets in subsequent reporting periods. A financial asset is credit impaired when one or more of the following events have occurred: i) Significant financial difficulty of the issuer or the borrower; ii) Breach of contract, such as a default; iii) It is becoming probable that the borrower will enter bankruptcy or undergo a financial reorganization; or iv) The disappearance of an active market for that financial asset because of financial difficulties. Cash equivalents include time deposits with original maturities within 3 months from the date of acquisition, which are highly liquid, readily convertible to a known amount of cash and are subject to an insignificant risk of changes in value and repurchase agreements collateralized by bonds. These cash equivalents are held for the purpose of meeting short-term cash commitments. iii. Investments in debt instruments at FVTOCI For the Group’s debt instruments that meet the following conditions are subsequently measured at FVTOCI: i) the debt instrument is held within a business model whose objective is achieved by both the collecting of contractual cash flows and the selling of the financial assets; and ii) the contractual terms of the debt instrument give rise on specified dates to cash flows that are solely payments of principal and interest on the principal amount outstanding. Investments in debt instruments at FVTOCI are subsequently measured at fair value. Changes in the carrying amounts of these debt instruments relating to changes in foreign currency exchange rates, interest income calculated using the effective interest method and impairment losses or reversals are recognized in profit or loss. Other changes in the carrying amount of these debt instruments are recognized in other comprehensive income and will be reclassified to profit or loss when the investment is disposed of. iv. Investments in equity instruments at FVTOCI On initial recognition, the Group make an irrevocable election to designate investments in equity instruments as at FVTOCI. Designation at FVTOCI is not permitted if the equity investment is held for trading or if it is contingent consideration recognized by an acquirer in a business combination. Investments in equity instruments at FVTOCI are subsequently measured at fair value with gains and losses arising from changes in fair value recognized in other comprehensive income and accumulated in other equity. The cumulative gain or loss will not be reclassified to profit or loss on disposal of the equity investments, instead, they will be transferred to retained earnings. Dividends on these investments in equity instruments are recognized in profit or loss when the Group’s right to receive the dividends is established, unless the dividends clearly represent a recovery of part of the cost of the investment. b) Impairment of financial assets and contract assets At each balance sheet date, the Group recognizes a loss allowance for expected credit losses on financial assets at amortized cost (including trade receivables) and investments in debt instruments that are measured at FVTOCI and The Group always recognizes lifetime Expected Credit Loss (“ECL”) for trade receivables and contract assets. For all other financial instruments, the Group recognizes lifetime ECL when there has been a significant increase in credit risk since initial recognition. If, on the other hand, the credit risk on the financial instrument has not increased significantly since initial recognition, the Group measures the loss allowance for that financial instrument at an amount equal to 12-month Expected credit losses reflect the weighted average of credit losses with the respective risks of a default occurring as the weights. Lifetime ECL represents the expected credit losses that will result from all possible default events over the expected life of a financial instrument. In contrast, 12-month The Group recognizes an impairment gain or loss in profit or loss for all financial instruments with a corresponding adjustment to their carrying amount through a loss allowance account, except for investments in debt instruments that are measured at FVTOCI, for which the loss allowance is recognized in other comprehensive income and does not reduce the carrying amount of the financial asset. c) Derecognition of financial assets The Group derecognizes a financial asset only when the contractual rights to the cash flows from the asset expire or when it transfers the financial asset and substantially all the risks and rewards of ownership of the asset to another entity. On derecognition of a financial asset at amortized cost in its entirety, the difference between the asset’s carrying amount and the sum of the consideration received and receivable is recognized in profit or loss. On derecognition of an investment in a debt instrument at FVTOCI, the difference between the asset’s carrying amount and the sum of the consideration received and receivable and the cumulative gain or loss which had been recognized in other comprehensive income is recognized in profit or loss. However, on derecognition of an investment in an equity instrument at FVTOCI, the difference between the asset’s carrying amount and the sum of the consideration received and receivable is recognized in profit or loss, and the cumulative gain or loss which had been recognized in other comprehensive income is transferred directly to retained earnings, without recycling through profit or loss. 2) Equity instruments Debt and equity instruments issued by a group entity are classified as either financial liabilities or as equity in accordance with the substance of the contractual arrangements and the definitions of a financial liability and an equity instrument. Equity instruments issued by a group entity are recognized at the proceeds received, net of direct issue costs. Repurchase of the Company’s own equity instruments is recognized in and deducted directly from equity. No gain or loss is recognized in profit or loss on the purchase, sale, issue or cancellation of the Company’s own equity instruments. 3) Financial liabilities a) Subsequent measurement All or at fair value through profit or loss: Financial liabilities are classified as at FVTPL when such financial liabilities are held for trading. Financial liabilities held for trading are stated at fair value, and any gains or losses on such financial liabilities are recognized in other gains or losses. Fair value is determined in the manner described in Note 34. b) Derecognition of financial liabilities The difference between the carrying amount of a financial liability derecognized and the consideration paid, including any non-cash 4) Derivative financial instruments The Group enters into a variety of derivative financial instruments to manage its exposure to interest rate and foreign exchange rate risks, including forward exchange contracts, swap contracts and target redemption forward contracts. Derivatives are initially recognized at fair value at the date on which the derivative contracts are entered into and are subsequently remeasured to their fair value at the end of each reporting period. The resulting gain or loss is recognized in profit or loss immediately unless the derivative is designated and effective as a hedging instrument; in which event, the timing of the recognition in profit or loss depends on the nature of the hedging relationship. When the fair value of a derivative financial instrument is positive, the derivative is recognized as a financial asset; when the fair value of a derivative financial instrument is negative, the derivative is recognized as a financial liability. Derivatives embedded in hybrid contracts that contain financial asset hosts that is within the scope of IFRS 9 are not separated; instead, the classification is determined in accordance with the entire hybrid contract. Derivatives embedded in non-derivative 5) Convertible bonds issued by the subsidiaries The component parts of compound instruments (i.e., convertible bonds) issued by the subsidiary are classified separately as financial liabilities and equity in accordance with the substance of the contractual arrangements and the definitions of a financial liability and an equity instrument. On initial recognition, the fair value of the liability component is estimated using the prevailing market interest rate for similar non-convertible instruments. This amount is recorded as a liability on an amortized cost basis using the effective interest method until extinguished upon conversion or upon the instrument’s maturity date. Any embedded derivative liability is measured at fair value. The conversion option classified as equity is determined by deducting the amount of the liability component from the fair value of the compound instrument as a whole. This is recognized and included in non-controlling interests, and is not subsequently remeasured. When the conversion option remains unexercised at maturity, the balance recognized in non-controlling interests will be transferred to capital surplus - the change of interest in subsidiaries. Transaction costs that relate to the issuance of the convertible bonds are allocated to the liability and equity components in proportion to the allocation of the gross proceeds. Transaction costs relating to the equity component are recognized directly in non-controlling interests. Transaction costs relating to the liability component are included in the carrying amount of the liability component.
Hedge Accounting	o. Hedge accounting The Group designates certain hedging instruments, which include derivatives, embedded derivatives and non-derivatives 1) Fair value hedges Gains or losses on hedging instruments that are designated and qualify as fair value hedges are recognized in profit or loss immediately, together with any changes in the fair value of the hedged asset or liability that are attributable to the hedged risk. The change in the fair value of the hedging instrument and the change in the hedged item attributable to the hedged risk are recognized in profit or loss in the line item relating to the hedged item. The Group discontinues hedge accounting only when the hedging relationship ceases to meet the qualifying criteria; for instance, when the hedging instrument expires or is sold, terminated or exercised. 2) Cash flow hedges The effective portion of gains or losses on hedging instruments that are designated and qualify as cash flow hedges is recognized in other comprehensive income. The gains or losses relating to the ineffective portion are recognized immediately in profit or loss. The associated gains or losses that were recognized in other comprehensive income are reclassified from equity to profit or loss as a reclassification adjustment in the line item relating to the hedged item in the same period when the hedged item affects profit or loss. If a hedge of a forecasted transaction subsequently results in the recognition of a non-financial non-financial non-financial non-financial The Group discontinues hedge accounting only when the hedging relationship cease to meet the qualifying criteria; for instance, when the hedging instrument expires or is sold, terminated, or exercised. The cumulative gain or loss on the hedging instrument that has been previously recognized in other comprehensive income from the period when the hedge was effective remains separately in equity until the forecast transaction occurs. When a forecast transaction is no longer expected to occur, the gain or loss accumulated in equity is recognized immediately in profit or loss. 3) Hedges of net investments in foreign operations Hedges of net investments in foreign operations are accounted for similarly to cash flow hedges. Any gains or losses on the hedging instrument relating to the effective portion of the hedge are recognized in other comprehensive income and accumulated under the heading of foreign currency translation reserve. The gains or losses relating to the ineffective portion are recognized immediately in profit or loss. The gains and losses on the hedging instrument relating to the effective portion of the hedge, which were accumulated in the foreign currency translation reserve, are reclassified to profit or loss on the disposal or partial disposal of a foreign operation.
Revenue Recognition	p. Revenue recognition The Group identifies the contracts with customers, allocates transaction prices to performance obligations and, when performance obligations are satisfied, recognizes revenues at fixed amounts as agreed in the contracts with taking estimated volume discounts into consideration. For contracts where the period between the date on which the Group transfers a promised good or service to a customer and the date on which the customer pays for that good or service is one year or less, the Group does not adjust the promised amount of consideration for the effects of a significant financing component. The Group’s duration of contracts with customers is expected to be one year or less, and the consideration from contracts with customers is included in transaction price and, therefore, can apply the practical expedient that not to disclose the performance obligations including (i) the aggregate amount of the transaction price allocated to the performance obligations that are not fully satisfied or have partially completed at the end of the reporting period, and (ii) the expected timing for recognition of revenue. The Group’s operating revenues include revenues from sale of goods and services as well as sale and leasing of real estate properties. When customers control goods while they are manufactured in progress, the Group measures the progress on the basis of costs incurred relative to the total expected costs as there is a direct relationship between the costs incurred and the progress of satisfying the performance obligations. Revenue and contract assets are recognized during manufacture and contract assets are reclassified to trade receivables when the manufacture is completed or when the goods are shipped upon customer’s request. The Group recognizes revenues and trade receivables when the goods are shipped or when the goods are delivered to the customer’s specific location because it is the time when the customer has full discretion over the manner of distribution and price to sell the goods, has the primary responsibility for sales to future customers and bears the risks of obsolescence. Revenues from sale of real estate properties are recognized when customers purchase real estate properties and complete the transfer procedures. Revenues from leasing real estate properties are recognized during leasing periods on the straight-line basis.
Leases	q. Leases At the inception of a contract, the Group assesses whether the contract is, or contains, a lease. For a contract that contains a lease component and non-lease non-lease 1) The Group as lessor Leases are classified as finance leases whenever the terms of a lease transfer substantially all the risks and rewards of ownership to the lessee. All other leases are classified as operating leases. When the Group subleases a right-of-use right-of-use Lease payments (less any lease incentives payable) from operating leases are recognized as income on a straight-line basis over the terms of the relevant leases. Initial direct costs incurred in obtaining operating leases are added to the carrying amounts of the underlying assets and recognized as expenses on a straight-line basis over the lease terms. 2) The Group as lessee The Group recognizes right-of-use low-value Right-of-use Right-of-use Right-of-use right-of-use Right-of-use right-of-use right-of-use right-of-use Lease liabilities are initially measured at the present value of the lease payments, which comprise fixed payments, in-substance Subsequently, lease liabilities are measured at amortized cost using the effective interest method, with interest expense recognized over the lease terms. When there is a change in a lease term, a change in the amounts expected to be payable under a residual value guarantee, a change in the assessment of an option to purchase an underlying asset, or a change in future lease payments resulting from a change in an index or a rate used to determine those payments, the Group remeasures the lease liabilities with a corresponding adjustment to the right-of-use right-of-use right-of-use right-of-use The Group negotiates with the lessor for rent concessions as a direct consequence of the COVID-19 to change the lease payments originally due by June 30, 2022, that results in the revised consideration for the lease substantially less than the consideration for the lease immediately preceding the change. There is no substantive change to other terms and conditions. The Group elects to apply the practical expedient to all of these rent concessions, and therefore, does not assess whether the rent concessions are lease modifications. Instead, the Group recognizes the reduction in lease payment in profit or loss as a deduction of expenses of variable lease payments, in the period in which the events or conditions that trigger the concession occurs, and makes a corresponding adjustment to the lease liability. Variable lease payments that do not depend on an index or a rate are recognized as expenses in the periods in which they are incurred.
Borrowing Costs	r. Borrowing costs Borrowing costs directly attributable to the acquisition, construction or production of qualifying assets are added to the cost of those assets, until such time as the assets are substantially ready for their intended use or sale. Investment income earned on the temporary investment of specific borrowings pending their expenditure on qualifying assets is deducted from the borrowing costs eligible for capitalization. Other than stated above, all other borrowing costs are recognized in profit or loss in the period in which they are incurred.
Government grants	s. Government grants Government grants related to income are not recognized until there is reasonable assurance that the Group will comply with the conditions attaching to them and that the grants will be received. Government grants are recognized in other income on a systematic basis over the periods in which the Group recognizes as expenses the related costs for which the grants are intended to compensate. Specifically, government grants whose primary condition is that the Group should purchase, construct or otherwise acquire non-current Government grants that are receivable as compensation for expenses or losses already incurred or for the purpose of giving immediate financial support to the Group with no future related costs are recognized in profit or loss in the period in which they become receivable. The benefit of a t l oa n received at
Employee Benefits	t. Employee benefits 1) Short-term employee benefits Liabilities recognized in respect of short-term employee benefits are measured at the undiscounted amount of the benefits expected to be paid in exchange for the related services. 2) Retirement benefits Payments to defined contribution retirement benefit plans are recognized as expenses when employees have rendered services entitling them to the contributions. Defined benefit costs (including service cost, net interest and remeasurement) under the defined benefit retirement benefit plans are determined using the projected unit credit method. Service cost (including current service cost and past service cost) and net interest on the net defined benefit liability (asset) are recognized as employee benefits expense in the period they occur. Remeasurement, comprising actuarial gains and losses and the return on plan assets (excluding interest), is recognized in other comprehensive income in the period in which they occur. Remeasurement recognized in other comprehensive income is reflected immediately in retained earnings and will not be reclassified to profit or loss. Net defined benefit liability (asset) represents the actual deficit (surplus) in the Group’s defined benefit plan. Any surplus resulting from this calculation is limited to the present value of any refunds from the plans or reductions in future contributions to the plans.
Share-based payment arrangements	u. Share-based payment arrangements The fair value at the grant date of the employee share options and restricted stocks non-controlling s tocks shares When restricted stocks stocks At each balance sheet date, the Group reviews its estimate of the number of employee share options and restricted st o cks non-controlling stocks
Taxation	v. Taxation Income tax expense represents the sum of the tax currently payable and deferred tax. 1) Current tax Income tax payable (recoverable) is based on taxable profit (loss) for the year determined according to the applicable tax laws of each tax jurisdiction. Taxable profit differs from net profit as reported in profit or loss because it excludes items of income or expense that are taxable or deductible in other years and it further excludes items that are never taxable or deductible. The Group’s liability for current tax is calculated using tax rates that have been enacted or substantively enacted by the end of the reporting period. Adjustments of prior years’ tax liabilities are added to or deducted from the current year’s tax provision. 2) Deferred tax Deferred tax is recognized on temporary differences between the carrying amounts of assets and liabilities in the consolidated financial statements and the corresponding tax bases used in the computation of taxable profit. If a temporary difference arises from the initial recognition (other than in a business combination) of assets and liabilities in a transaction that affects neither the taxable profit nor the accounting profit, the resulting deferred tax asset or liability is not recognized. In addition, a deferred tax liability is not recognized on taxable temporary differences arising from the initial recognition of goodwill. Deferred tax liabilities are generally recognized for all taxable temporary differences. Deferred tax assets are generally recognized for all deductible temporary differences, unused loss carryforwards and unused tax credits for capital expenditure to the extent that it is probable that taxable profits will be available against which those deductible temporary differences can be utilized. Deferred tax liabilities are recognized for taxable temporary differences associated with investments in subsidiaries and associates, except where the Group is able to control the reversal of the temporary differences and it is probable that the temporary difference will not reverse in the foreseeable future. Deferred tax assets arising from deductible temporary difference associated with such investments and interests are only recognized to the extent that it is probable that there will be sufficient taxable profits against which to utilize the benefits of the temporary differences and they are expected to reverse in the foreseeable future. The carrying amount of deferred tax assets is reviewed at each balance sheet date and reduced to the extent that it is no longer probable that sufficient taxable profits will be available to allow all or part of the assets to be recovered. A previously unrecognized deferred tax asset is also reviewed at each balance sheet date and recognized to the extent that it has become probable that future taxable profit will allow the deferred tax asset to be recovered. Deferred tax liabilities and assets are measured at the tax rates that are expected to apply in the period in which the liabilities are settled or assets are realized, based on tax rates (and tax laws) that have been enacted or substantively enacted by the balance sheet date. The measurement of deferred tax liabilities and assets reflects the tax consequences that would follow from the manner in which the Group expects, at the balance sheet date, to recover or settle the carrying amount of its assets and liabilities. 3) Current and deferred tax for the year Current and deferred tax are recognized in profit or loss, except when they relate to items that are recognized in other comprehensive income or directly in equity, in which case, the current and deferred tax are also recognized in other comprehensive income or directly in equity, respectively. Where current tax or deferred tax arises from the initial accounting for a business combination, the tax effect is included in the accounting for the business combination.
U.S. Dollar Amounts	w. U.S. Dollar Amounts A translation of the consolidated financial statements into U.S. dollars is included solely for the convenience of the readers and has been translated from New Taiwan dollar (NT$) at the exchange rate as set forth in the statistical release by the U.S. Federal Reserve Board of the United States, which was NT$27.74 to US$1.00 as of December 31, 2021. The translation should not be construed as a representation that the NT$ amounts have been, could have been, or could in the future be, converted into U.S. dollars at this or any other rate of exchange.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2021
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Summary of Subsidiaries	2) Subsidiaries included in consolidated financial statements were as follows: Establishment and Operating Percentage of Ownership (%) December 31 Name of Investor Name of Investee Main Businesses Location 2020 2021 The Company ASE Engaged in the packaging and testing of semiconductors R.O.C. 100.0 100.0 USI Inc. (“USIINC”) Holding company R.O.C. 100.0 100.0 SPIL Engaged in the assembly, testing and turnkey services of integrated circuit R.O.C. 100.0 100.0 ASE A.S.E. Holding Limited Holding company Bermuda 100.0 100.0 J & R Holding Limited (“J&R Holding”) Holding company Bermuda 100.0 100.0 Innosource Limited Holding company British Virgin Islands 100.0 100.0 Omniquest Industrial Limited Holding company British Virgin Islands 71.0 71.0 ASE Marketing & Service Japan Co., Ltd. Engaged in marketing and sales services Japan 100.0 100.0 ASE Test, Inc. Engaged in the testing of semiconductors R.O.C. 100.0 100.0 Luchu Development Corporation Engaged in the development of real estate properties R.O.C. 67.1 67.1 Advanced Microelectronic Products Inc. (“AMPI”) Engaged in the manufacturing of integrated circuit R.O.C. 7.6 7.6 ASE Test, Inc. Alto Enterprises Limited Holding company British Virgin Islands 100.0 100.0 Super Zone Holdings Limited Holding company Hong Kong 100.0 100.0 Luchu Development Corporation Engaged in the development of real estate properties R.O.C. 19.0 19.0 TLJ Intertech Inc. Engaged in information software services R.O.C. 60.0 60.0 MingFeng Information Service Corp., Ltd. In the process of liquidation (Liquidation completed in February 2022) R.O.C. 100.0 100.0 AMPI Engaged in the manufacturing of integrated circuit R.O.C. 43.4 43.4 A.S.E. Holding Limited ASE Investment (Labuan) Inc. Holding company Malaysia 70.1 70.1 ASE Test Limited (“ASE Test”) Holding company Singapore 10.2 10.2 ASE Technology Partners, Limited Holding company and was established in August 2021 British Cayman Islands — 100.0 Integrated Solutions Enterprise Europe Trading company, and was acquired in October 2021 (Note 29) Belgium — 100.0 J&R Holding ASE Test Holding company Singapore 89.8 89.8 Omniquest Industrial Limited Holding company British Virgin Islands 8.4 8.4 J&R Industrial Inc. Engaged in leasing equipment and investing activity R.O.C. 100.0 100.0 ASE Japan Co., Ltd. Engaged in the packaging and testing of semiconductors Japan 100.0 100.0 ASE (U.S.) Inc. After-sales service and sales support U.S.A. 100.0 100.0 Global Advanced Packaging Technology Limited Holding company British Cayman Islands 100.0 100.0 Anstock Limited Liquidated in June 2021 British Cayman Islands 100.0 — Anstock II Limited Liquidated in June 2021 British Cayman Islands 100.0 — Suzhou ASEN Semiconductors Co., Ltd. (“ASEN”) Engaged in the packaging and testing of semiconductors (organizational adjustment through exchanged shares to Global Advanced Packaging Test (Hong Kong) Limited in September 2021) Suzhou, China 100.0 — Innosource Limited Omniquest Industrial Limited Holding company British Virgin Islands 20.6 20.6 ASE (Shanghai) Inc. Engaged in the production of substrates Shanghai, China 8.5 8.5 Omniquest Industrial Limited ASE Corporation Holding company British Cayman Islands 100.0 100.0 Alto Enterprises Limited ASE (Kunshan) Inc. Engaged in the packaging and testing of semiconductors Kun Shan, China 22.9 (Note 2 ) ASE Investment (Kun Shan) Limited Holding company Kun Shan, China 85.9 85.9 Super Zone Holdings Limited Advanced Semiconductor Engineering (China) Ltd. Engaged in the packaging and testing of semiconductors, after-sale services, advisory and lease of factory Shanghai, China 100.0 100.0 ASE Investment (Labuan) Inc. ASE (Korea) Inc. (“ASE Korea”) Engaged in the packaging and testing of semiconductors Korea 100.0 100.0 ASE Technology Partners, Limited ASE Technology Acquisition Corporation Holding company and was established in August 2021 British Cayman Islands — 100.0 ASE Korea ASE (Weihai) Inc. Engaged in the packaging and testing of semiconductors (disposed to J&R Holding and organizational adjustment through exchanged shares from J&R Holding to GAPT (Hong Kong) Limited in October 2021) Shandong, China 100.0 — ASE Test ASE Test Holdings, Ltd. Holding company British Cayman Islands 100.0 100.0 ASE Holdings (Singapore) Pte Ltd Holding company Singapore 100.0 100.0 ASE Investment (Labuan) Inc. Holding company Malaysia 29.9 29.9 ASE Singapore Pte. Ltd. Engaged in the packaging and testing of semiconductors Singapore 100.0 100.0 ASE Test Holdings, Ltd. ISE Labs, Inc. Engaged in the testing of semiconductors U.S.A. 100.0 100.0 Establishment and Operating Percentage of Ownership (%) December 31 Name of Investor Name of Investee Main Businesses Location 2020 2021 ISE Labs, Inc. ISE Services, Inc. Engaged in wafer procurement and customer product management services U.S.A. 100.0 100.0 ASE Holdings (Singapore) Pte Ltd ASE Electronics (M) Sdn. Bhd. Engaged in the packaging and testing of semiconductors Malaysia 100.0 100.0 Global Advanced Packaging Technology Limited ASE Assembly & Test (Shanghai) Limited Engaged in the packaging and testing of semiconductors and leasing of properties Shanghai, China 100.0 100.0 ASE Advanced Semiconductor (Shanghai) Limited Engaged in the packaging and testing of semiconductors (disposed to ASEN in November 2021) Shanghai, China 100.0 — GAPT Holding Limited Holding company and was established in August 2021 British Virgin Islands — (Note 2 ) GAPT Holding Limited Global Advanced Packaging Test (Hongkong) Limited Engaged in the trading of substrates and was established in August 2021 Hong Kong — (Note 2 ) Global Advanced Packaging Test (Hongkong) Limited Suzhou ASEN Semiconductors Co., Ltd. (“ASEN”) Engaged in the packaging and testing of semiconductors (acquired from J&R Holding in September 2021 ) Suzhou, China — (Note 2 ) ASE (Weihai) Inc. Engaged in the packaging and testing of semiconductors (acquired from J&R Holding in October 2021 through share exchange under restructure ) Shandong, China — (Note 2 ) ASEN ASE Advanced Semiconductor (Shanghai) Limited Engaged in the packaging and testing of semiconductors (acquired from Global Advanced Packaging Technology Limited in November 2021) Shanghai, China — (Note 2 ) ASE Assembly & Test (Shanghai) Limited ASE Investment (Kun Shan) Limited Holding company Kun Shan, China 14.1 14.1 Wuxi Tongzhi Microelectronics Co., Ltd. Engaged in the packaging and testing of semiconductors Wuxi, China 100.0 100.0 ISE Labs, China, Ltd. Engaged in the testing of semiconductor Shanghai, China 100.0 100.0 Shanghai Ding Hui Real Estate Development Co., Ltd. (“DH”) Engaged in the development, construction and sale of real estate properties Shanghai, China 60.0 60.0 DH Shanghai Ding Qi Property Management Co., Ltd. Engaged in the management of real estate properties Shanghai, China 100.0 100.0 Shanghai Ding Wei Real Estate Development Co., Ltd. (“DW”) Engaged in the development, construction and leasing of real estate properties Shanghai, China 100.0 100.0 Shanghai Ding Yu Real Estate Development Co., Ltd. Engaged in the development, construction and leasing of real estate properties Shanghai, China 100.0 100.0 Kun Shan Ding Hong Real Estate Development Co., Ltd Engaged in the development, construction and leasing of real estate properties Kun Shan, China 100.0 100.0 Shanghai Ding Xu Property Management Co., Ltd. Engaged in the management of real estate properties Shanghai, China 100.0 100.0 Shanghai Dingyao Estate Development Co., Ltd. Engaged in the management of real estate properties Shanghai, China 100.0 100.0 Shanghai Ding Fan Business Management Co., Ltd. Engaged in the management of real estate properties (acquired from DW in November 2020) Shanghai, China 100.0 100.0 ASE Investment (Kun Shan) Limited ASE (Kun s Engaged in the packaging and testing of semiconductors Kun Shan, China 49.3 (Note 2 ) ASE Corporation ASE Mauritius Inc. Holding company Mauritius 100.0 100.0 ASE Labuan Inc. Holding company Malaysia 100.0 100.0 ASE Mauritius Inc. ASE (Kunshan) Inc. Engaged in the packaging and testing of semiconductors Kun Shan, China 27.8 (Note 2 ) ASE (Shanghai) Inc. Engaged in the production of substrates Shanghai, China 91.5 91.5 ASE Labuan Inc. ASE Electronics Inc. Engaged in the production of substrates R.O.C. 100.0 100.0 ASE (Shanghai) Inc. Advanced Semiconductor Engineering (HK) Limited Engaged in the trading of substrates Hong Kong 100.0 100.0 Shanghai Ding Hui Real Estate Development Co., Ltd. Engaged in the development, construction and sale of real estate properties Shanghai, China 40.0 40.0 Universal Scientific Industrial (Shanghai) Co., Ltd. (“USISH”) Engaged in the designing, manufacturing and sales of electronic components Shanghai, China 0.8 0.8 USIINC Huntington Holdings International Co., Ltd. Holding company British Virgin Islands 100.0 100.0 Huntington Holdings International Co., Ltd. Unitech Holdings International Co., Ltd. Holding company British Virgin Islands 100.0 100.0 Real Tech Holdings Limited Holding company British Virgin Islands 100.0 100.0 Universal ABIT Holding Co., Ltd. In the process of liquidation British Cayman Islands 100.0 100.0 Real Tech Holdings Limited USI Enterprise Limited (“USIE”) Engaged in the service of investment advisory and warehousing management Hong Kong 95.9 100.0 USIE USISH Engaged in the designing, manufacturing and sales of electronic components Shanghai, China 76.6 77.1 USISH Universal Global Technology Co., Limited Holding company Hong Kong 100.0 100.0 Establishment and Operating Percentage of Ownership (%) December 31 Name of Investor Name of Investee Main Businesses Location 2020 2021 Universal Global Technology (Kunshan) Co., Ltd. (“UGKS”) Engaged in the designing and manufacturing of electronic components Kun Shan, China 100.0 100.0 Universal Global Technology (Shanghai) Co., Ltd. Engaged in the processing and sales of computer and communication peripherals as well as business in import and export of goods and technology Shanghai, China 100.0 100.0 Universal Global Electronics (Shanghai) Co., Ltd. Engaged in the sales of electronic components and telecommunications equipment Shanghai, China 100.0 100.0 USI Electronics (Shenzhen) Co., Ltd. Engaged in the design, manufacturing and sales of motherboards and computer peripherals Shenzhen, China 50.0 50.0 Universal Global Technology (Huizhou) Co., Ltd. Engaged in the research and manufacturing of new electronic applications, communications, computers and other electronics products and also provided auxiliary technical services as well as import and export services Huizhou, China 100.0 100.0 FINANCIERE AFG (“FAFG”) Holding company France 10.4 10.4 Universal Global Technology Co., Limited Universal Global Industrial Co., Limited Engaged in manufacturing, trading and investing activity Hong Kong 100.0 100.0 Universal Global Scientific Industrial Co., Ltd. (“UGTW”) Engaged in the manufacturing of components of telecommunication and cars and provision of related R&D services R.O.C. 100.0 100.0 USI America Inc. Engaged in the manufacturing and processing of motherboards and wireless network communication and provision of related technical service U.S.A. 100.0 100.0 Universal Scientific Industrial De Mexico S.A. De C.V. Engaged in the assembling of motherboards and computer components Mexico 100.0 100.0 USI Japan Co., Ltd. Engaged in the manufacturing and sales of computer peripherals, integrated chip and other related accessories Japan 100.0 100.0 USI Electronics (Shenzhen) Co., Ltd. Engaged in the design, manufacturing and sales of motherboards and computer peripherals Shenzhen, China 50.0 50.0 Universal Global Electronics Co., Ltd. Engaged in accepting and outsourcing orders as well as sales of electronic components and service of technical advisory Hong Kong 100.0 100.0 Universal Scientific Industrial (France) (“USIFR”) Engaged in investing activities France 100.0 100.0 UNIVERSAL INDUSTRIA L TNAM CO ., Engaged in IC assembly for wearable devices and was established in July 2020. Vietnam 100.0 100.0 Universal Global Industrial Co., Limited Universal Scientific Industrial De Mexico S.A. De C.V. Engaged in the assembling of motherboards and computer components Mexico (Note 1 ) (Note 1 ) UGTW Universal Scientific Industrial Co., Ltd. (“USI”) Engaged in the manufacturing, processing and sales of computers, computer peripherals and related accessories R.O.C. 100.0 100.0 Universal Global Electronics Co., Ltd. Universal Scientific Industrial Poland Sp. z o.o. (“USIPL”) Engaged in the design and manufacturing of electronic components and new electronic applications. Poland 100.0 100.0 Universal Global Electronics (Shanghai) Co., Ltd. USI Science and Technology (Shenzhen) Co., Ltd. Engaged in the design of electronic components, service of technical advisory; wholesale of electronic components and communication peripherals as well as business in import and export of goods and management of properties. Established in November 2020. Shenzhen, China 100.0 100.0 USIFR FAFG Holding company France 89.6 89.6 ASTEELFLASH GROUP Holding company (disposed to FAFG in October 2021) France (Note 1 ) — Establishment and Operating Percentage of Ownership (%) December 31 Name of Investor Name of Investee Main Businesses Location 2020 2021 FAFG ASTEELFLASH GROUP Holding company (acquired 1 share from Universal Scientific Industrial (France) in October 2021) France 100.0 100.0 MANUFACTURING POWER TUNISIA Engaged in the design and manufacturing of electronic components Tunisia 0.1 0.1 ASTEELFLASH MEXICO S.A. de C.V. Engaged in the design and manufacturing of electronic components Mexico 0.1 0.1 ASTEELFLASH GROUP ASTEELFLASH (BEDFORD) LIMITED Engaged in the design and manufacturing of electronic components United Kingdom 100.0 100.0 ASTEELFLASH FRANCE Engaged in the design and manufacturing of electronic components France 99.9 99.9 ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia 100.0 100.0 ASTEELFLASH HONG KONG LIMITED Holding company Hong Kong 100.0 100.0 ASTEELFLASH MEXICO S.A. de C.V. Engaged in the design and manufacturing of electronic components Mexico 99.9 99.9 ASTEELFLASH GERMANY GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 MANUFACTURING POWER TUNISIA Engaged in the design and manufacturing of electronic components Tunisia 99.9 99.9 ASTEELFLASH US HOLDING CORP. Holding company U.S.A. 100.0 100.0 ASTEEL ELECTRONIQUE FOUCHANA Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH TUNISIE S.A. in June 2021) Tunisia (Note 1 ) — AFERH TUNISIE Engaged in the management, training and consulting of human resources Tunisia 0.5 0.5 ASTEEL ELECTRONICS MANUFACTURING SERVICES Engaged in the design and manufacturing of electronic components Tunisia 0.1 0.1 ASTEELFLASH PLZEN S.R.O. Engaged in the design and manufacturing of electronic components (acquired from ASTEELFLASH GERMANY GmbH in April 2021) Czech Republic — 100.0 ASTEELFLASH (BEDFORD) LIMITED ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1 ) (Note 1 ) ASTEELFLASH TECHNOLOGIE ASTEELFLASH FRANCE Engaged in the design and manufacturing of electronic components France (Note 1 ) (Note 1 ) ASTEELFLASH FRANCE SCI CHASSET Engaged in the management and operation of real estate properties and holding the ownership of real estate properties (Liquidated in July 2021) France 100.0 — AFERH Engaged in the management, training and consulting of human resources (Liquidated in July 2021) France 100.0 — ASTEEL ELECTRONICS MANUFACTURING SERVICES Engaged in the design and manufacturing of electronic components Tunisia 99.9 99.9 ASTEEL ELECTRONIQUE FOUCHANA Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH TUNISIE S.A. in June 2021) Tunisia 94.2 — ASTEELFLASH TECHNOLOGIE Engaged in projection of plastic and the design and manufacturing of industrial components France 100.0 100.0 ASTEELFLASH BRETAGNE Engaged in the design and manufacturing of electronic components France 100.0 100.0 ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1 ) (Note 1 ) ASTEELFLASH TUNISIE S.A. ASTEEL ELECTRONIQUE TUNISIE Engaged in the design and manufacturing of electronic components (merged by ASTEELFLASH TUNISIE S.A.in December 2021) Tunisia 100.0 — ASTEEL ELECTRONIQUE FOUCHANA Engaged in the design and manufacturing of electronic components (acquired from ASTEELFLASH GROUP, ASTEELFLASH FRANCE, Asteelflash Suzhou Co., Ltd. and ASTEELFLASH USA CORP.in June 2021 and merged by ASTEELFLASH TUNISIE S.A. in December 2021) Tunisia (Note 1 ) — AFERH AFERH TUNISIE Engaged in the management, training and consulting of organization and human resources Tunisia 99.5 99.5 ASTEELFLASH HONG KONG LIMITED Asteelflash S ou Co., Ltd . Engaged in the design and manufacturing of electronic components Suzhou, China 100.0 100.0 Asteelflash Suzhou Co., Ltd. A STE EL ELECT R ONIQUE FO UCHANA Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH TUNISIE S.A. in June 2021) Tunisia (Note 1 ) — ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1 ) (Note 1 ) ASTEELFLASH GERMANY GmbH ASTEELFLASH HERSFELD GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 ASTEELFLASH EBERBACH GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 Establishment and Operating Percentage of Ownership (%) December 31 Name of Investor Name of Investee Main Businesses Location 2020 2021 ASTEELFLASH BONN GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 ASTEELFLASH SCHWANDORF GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 ASTEELFLASH PLZEN S.R.O. Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH GROUP in April 2021) Czech Republic 100.0 — ASTEELFLASH DESIGN SOLUTIONS HAMBOURG GmbH Engaged in the design and manufacturing of electronic components Germany 100.0 100.0 EN ELECTRONICNETWORK SRL Engaged in the design and manufacturing of electronic components Romania 100.0 100.0 ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1) (Note 1 ) ASTEELFLASH MEXICO S.A. de C.V. ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1) (Note 1 ) ASTEELFLASH US HOLDING CORP. ASTEELFLASH USA CORP. Engaged in the design and manufacturing of electronic components U.S.A. 100.0 100.0 ASTEELFLASH USA CORP. ASTEEL ELECTRONIQUE FOUCHANA Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH TUNISIE S.A. in June 2021) Tunisia (Note 1) — ASTEELFLASH TUNISIE S.A. Engaged in the design and manufacturing of electronic components Tunisia (Note 1) (Note 1 ) SPIL SPIL (B.V.I.) Holding Limited Engaged in investing activities British Virgin Islands 100.0 100.0 Siliconware Investment Co., Ltd. Engaged in investing activities R.O.C. 100.0 100.0 SPIL (B.V.I.) Holding Limited Siliconware USA, Inc. Engaged in marketing activities U.S.A. 100.0 100.0 SPIL (Cayman) Holding Limited Engaged in investing activities British Cayman Islands 100.0 100.0 SPIL (Cayman) Holding Limited Siliconware Technology (Suzhou) Limited (“SZ”) Engaged in the packaging and testing of semiconductors Suzhou, China 100.0 100.0 Note 1: The number of shares held was 1 share or 3 shares and the percentage of ownership was less than 0.1%. Note 2: In December 2021, the Company’s board of directors resolved to dispose its 100% shareholdings in those subsidiaries, which were settled in December 2021 and resulted in losing its control over those subsidiaries. Refer to Note 30 DISPOSAL OF SUBSIDIARIES for related disclosure.

Cash and Cash Equivalents (Tabl

Cash and Cash Equivalents (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Cash and Cash Equivalents	December 31 2020 2021 NT$ NT$ US$ (Note 4) Cash on hand $ 6,073 $ 5,638 $ 203 Checking accounts and demand deposits 48,734,866 47,094,687 1,697,718 Cash equivalents (time deposits with original maturity of less than three months and repurchase agreements collateralized by bonds) 2,797,132 28,973,020 1,044,449 $ 51,538,071 $ 76,073,345 $ 2,742,370

Financial Instruments at Fair_2

Financial Instruments at Fair Value Through Profit or Loss (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Financial Instruments at Fair Value Through Profit or Loss	December 31 2020 (Retrospectively Adjusted) 2021 NT$ NT$ US$ (Note 4) Financial assets mandatorily classified as at FVTPL Derivative instruments (non-designated Swap contracts $ 99,312 $ 85,629 $ 3,087 Forward exchange contracts 122,511 23,373 843 Redemption option and put option of convertible bonds - 8,463 305 Target redemption forward contracts - 500 18 Non-derivative Quoted ordinary shares 4,064,438 2,683,193 96,726 Private-placement funds 1,124,754 1,322,686 47,682 Unquoted preferred shares 385,440 583,270 21,026 Contingent considerations (Note 29) 387,790 394,943 14,237 Open-end 339,338 334,223 12,049 6,523,583 5,436,280 195,973 Current 4,342,605 2,933,446 105,748 Non-current $ 2,180,978 $ 2,502,834 $ 90,225 Financial liabilities held for trading Derivative instruments (non-designated Swap contracts $ 1,448,972 $ 360,797 $ 13,006 Forward exchange contracts 9,020 56,863 2,050 Target redemption forward contracts 79,216 - - Current $ 1,537,208 $ 417,660 $ 15,056
Summary of Outstanding Contracts Not Accounted for Hedge Accounting	At each balance sheet date, outstanding swap contracts not accounted for hedge accounting were as follows: Notional Amount Currency Maturity Period (In Thousands) December 31, 2020 Sell NT$/Buy US$ 2021.01 2021.12 NT$51,140,082/US$1,755,000 Sell US$/Buy RMB 2021.01 2021.02 US$59,793/RMB395,742 Sell US$/Buy HKD 2021.0 US$13,804/HKD$107,000 Sell US$/Buy JPY 2021.0 US$41,630/JPY4,300,000 Sell US$/Buy KRW 2021.0 US$30,000/KRW33,066,000 Sell US$/Buy NT$ 2021.01 2021.02 US$675,240/NT$19,073,846 December 31, 2021 Sell RMB/Buy US$ 2022.0 RMB2,617,518/US$409,000 Sell NT$/Buy US$ 2022.01 2022.12 NT$52,916,127/US$1,903,000 Sell US$/Buy RMB 2022.0 US$54,415/RMB349,800 Sell US$/Buy JPY 2022.0 US$17,671/JPY2,000,000 Sell US$/Buy KRW 2022.0 US$37,500/KRW44,418,750 Sell US$/Buy NT$ 2022.01 2022.04 US$570,130/ N T $ At each balance sheet date, outstanding forward exchange contracts not accounted for hedge accounting were as follows : Notional Amount Currency Maturity Period (In Thousands) December 31, 2020 Sell RMB/Buy US$ 2021.01 RMB756,946/US$116,093 Sell HKD/Buy US$ 2021.01 HKD4,100/US$529 Sell NT$/Buy US$ 2021.01 2021.02 NT$2,667,230/US$95,000 Sell US$/Buy RMB 2021.01 2021.04 US$363,000/RMB2,385,500 Sell US$/Buy EUR 2021.01 US$1,607/EUR1,320 Sell US$/Buy JPY 2021.01 2021.04 US$100,076/JPY10,405,845 Sell US$/Buy KRW 2021.0 US$16,000/KRW17,575,300 Sell US$/Buy MYR 2021.01 2021.04 US$24,000/MYR98,737 Sell US$/Buy NT$ 2021.01 2021.02 US$27,470/NT$776,867 Sell US$/Buy SGD 2021.01 2021.04 US$18,500/SGD24,868 December 31, 2021 Sell RMB/Buy JPY 2022.01 RMB35,127/JPY630,000 Sell RMB/Buy US$ 2022.01 RMB727,645/US$114,000 Sell NT$/Buy US$ 2022.01 2022.03 NT$3,465,805/US$125,000 Sell US$/Buy RMB 2022.01 2022.06 US$265,000/RMB1,701,695 Sell US$/Buy EUR 2022.01 US$460/EUR407 Sell US$/Buy JPY 2022.01 2022.02 US$94,747/JPY10,789,851 Sell US$/Buy MYR 2022.01 2022.02 US$8,000/MYR33,430 Sell US$/Buy NT$ 2022.01 US$10,000/NT$277,735 Sell US$/Buy SGD 2022.01 2022.02 US$16,900/SGD22,925 As of each balance sheet date, outstanding target redemption forward contracts not accounted for hedge accounting were as follows: Notional Amount Currency Maturity Period (In Thousands) December 31, 2020 Sell EUR/Buy US$ 2022.04 2022.06 EUR23,279/US$27,475 December 31, 2021 Sell EUR/Buy US$ 2022.04 2022.06 EUR2,982/US$3,475 The target redeemable forward contracts held by subsidiaries are weekly settled. If the market exchange rate is lower than the execution rate at the time of settlement, the contract will be settled at the nominal amount, whereas if the market exchange rate is higher than the execution rate, the contract will be settled at a leveraged nominal amount (twice the nominal amount). The contracts last until all the nominal amount of US$ position is fully settled. However, when the accumulated excess of the execution rates over the market exchange rates reach the agreed threshold after the weekly settlement, the contracts will be automatically early terminated.

Financial Assets at Fair Valu_2

Financial Assets at Fair Value Through Other Comprehensive Income - (FVTOCI) (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Financial Assets at Fair Value Through Other Comprehensive Income	December 31 2020 2021 NT$ NT$ US$ (Note 4) Investments in equity instruments at FVTOCI $ 728,398 $ 943,354 $ 34,007 Investments in debt instruments at FVTOCI 1,012,736 1,076,458 38,805 $ 1,741,134 $ 2,019,812 $ 72,812
Summary of Investments in Equity Instruments at Fair Value Through Other Comprehensive Income	a. Investments in equity instruments at FVTOCI December 31 2020 2021 NT$ NT$ US$ (Note 4) Unquoted ordinary shares $ 567,377 $ 820,779 $ 29,588 Quoted ordinary shares — 102,124 3,682 Unquoted preferred shares 151,329 11,245 405 Limited partnership 9,692 9,206 332 $ 728,398 $ 943,354 $ 34,007
Summary of Investments in Debt Instruments at Fair Value Through Other Comprehensive Income	b. Investments in debt instruments at FVTOCI December 31 2020 2021 NT$ NT$ US$ (Note 4) Unsecured subordinate corporate bonds $ 1,012,736 $ 1,076,458 $ 38,805

Trade Receivables, Net (Tables)

Trade Receivables, Net (Tables)	12 Months Ended
	Dec. 31, 2021
Statement [LineItems]
Summary of Trade Receivables, Net	December 31 2020 2021 NT$ NT$ US$ (Note 4) At amortized cost Gross carrying amount $ 91,304,934 $ 109,473,101 $ 3,946,399 Less: Allowance for impairment loss 97,358 103,353 3,726 91,207,576 109,369,478 3,942,673 At FVTOCI 626,413 6,092,462 219,627 $ 91,833,989 $ 115,462,210 $ 4,162,300
Summary of Loss Allowance of Trade Receivables Based on Group's Provision Matrix	The following table details the loss allowance of trade receivables based on the Group’s provision matrix. December 31, 2020 Not Past Due Overdue 1 to 30 days Overdue 31 to 90 Days Overdue Over 91 Days Individually Total NT$ NT$ NT$ NT$ NT$ NT$ Expected credit loss rate 0% 0%-10% 0%-70% 1%-100% 50%-100% Gross carrying amount $ 86,820,792 $ 3,823,249 $ 557,487 $ 92,873 $ 10,533 $ 91,304,934 Loss allowance (Lifetime ECLs) (18,911 ) (2,053 ) (20,629 ) (45,232 ) (10,533 ) (97,358 ) $ 86,801,881 $ 3,821,196 $ 536,858 $ 47,641 $ — $ 91,207,576 December 31, 2021 Not Past Due Overdue 1 to 30 days Overdue 31 to 90 Days Overdue Over 91 Days Individually Total NT$ NT$ NT$ NT$ NT$ NT$ Expected credit loss rate 0% 0%-10% 0%-70% 1%-100% 0%-100% Gross carrying amount $ 105,538,390 $ 3,136,438 $ 609,695 $ 99,118 $ 89,460 $ 109,473,101 Loss allowance (Lifetime ECLs) (18,062 ) (1,811 ) (22,785 ) (46,337 ) (14,358 ) (103,353 ) $ 105,520,328 $ 3,134,627 $ 586,910 $ 52,781 $ 75,102 $ 109,369,748 Not Past Due Overdue 1 to 30 days Overdue 31 to 90 Days Overdue Over 91 Days Individually Total US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Expected credit loss rate 0% 0%-10% 0%-70% 1%-100% 0%-100% Gross carrying amount $ 3,804,556 $ 113,066 $ 21,979 $ 3,573 $ 3,225 $ 3,946,399 Loss allowance (Lifetime ECLs) (651 ) (65 ) (821 ) (1,671 ) (518 ) (3,726 ) $ 3,803,905 $ 113,001 $ 21,158 $ 1,902 $ 2,707 $ 3,942,673 The movements of the loss allowance of trade receivables were as f o December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Balance at January 1 $ 155,389 $ 136,497 $ 97,358 $ 3,510 Net remeasurement of loss allowance (38,277 ) (55,742 ) 17,078 616 Reclassification (5,877 ) (6,970 ) — — Acquisition through business combinations 25,553 32,460 — — Amounts written off — (3,944 ) (399 ) (14 ) Disposal of subsidiaries — — (4,637 ) (167 ) Effects of foreign currency exchange differences (291 ) (4,943 ) (6,047 ) (219 ) Balance at December 31 $ 136,497 $ 97,358 $ 103,353 $ 3,726
Summary of Loss Allowance For Current Financial Assets At Fair Value Routed Through Other Comprehensive Income	The following table details the loss allowance of trade receivables at FVTOCI based on the Group’s provision matrix. December 31, 2020 Not Past Due Overdue 1 to 30 days Overdue 31 to 90 Days Overdue Over 91 Days Individually Total NT$ NT$ NT$ NT$ NT$ NT$ Expected credit loss rate 0% 0% 0% — — Gross carrying amount $ 613,968 $ 9,874 $ 2,571 $ — $ — $ 626,413 Loss allowance (Lifetime ECLs) — — — — — — $ 613,968 $ 9,874 $ 2,571 $ — $ — $ 626,413 December 31, 2021 Not Past Due Overdue 1 to 30 days Overdue 31 to 90 Days Overdue Over 91 Days Individually Total NT$ NT$ NT$ NT$ NT$ NT$ Expected credit loss rate 0% 0% 0% 0% 0% Gross carrying amount $ 5,991,543 $ 9,415 $ 91,493 $ 11 $ — $ 6,092,462 Loss allowance (Lifetime ECLs) — — — — — — $ 5,991,543 $ 9,415 $ 91,493 $ 11 $ — $ 6,092,462 Not Past Due Overdue 1 to 30 days Overdue 31 to 90 Days Overdue Over 91 Days Individually Total US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Expected credit loss rate 0% 0% 0% 0% 0% Gross carrying amount $ 215,989 $ 340 $ 3,298 $ 0 $ — $ 219,627 Loss allowance (Lifetime ECLs) — — — — — — $ 215,989 $ 340 $ 3,298 $ 0 $ — $ 219,627
Disclosure of transferred financial assets that are not derecognised in their entirety	The f ollowing s the Counterparty Receivables Reclassified Advances Received- Unused Advances Annual December 31, 2020 BNP Paribas EUR 16,691 EUR 15,315 EUR 14,481 EUR 1,376 0.80 HSBC EUR 6,773 EUR 6,456 EUR 5,779 EUR 317 1.45 Citibank Taiwan Ltd. US$ 94,471 US$ — US$ — US$ 94,471 0.84-0.95 Standard Chartered Bank US$ 53,800 US$ — US$ — US$ 53,800 0.91 First Commercial Bank NT$ 6,879 NT$ — NT$ — NT$ 6,879 1.95 December 31, 2021 BNP Paribas EUR 12,115 EUR 12,081 EUR 11,475 EUR 34 0.80 First Commercial Bank NT$ 8,565 NT$ — NT$ — NT$ 8,565 1.95

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Inventories	December 31 2020 (Retrospectively Adjusted) 2021 NT$ NT$ US$ (Note 4) Finished goods $ 8,822,632 $ 8,454,783 $ 304,787 Work in process 6,856,405 7,950,743 286,617 Raw materials 29,428,008 46,978,647 1,693,534 Supplies 2,691,779 3,339,042 120,369 Raw materials and supplies in transit 791,610 1,109,766 40,006 $ 48,590,434 $ 67,832,981 $ 2,445,313

Inventories Related to Real E_2

Inventories Related to Real Estate Business (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Inventories Related to Real Estate Business	December 31 2020 2021 NT$ NT$ US$ (Note 4) Land and buildings held for sale $ 625,791 $ 667,630 $ 24,067 Construction in progress 11,058,328 2,956,958 106,596 Land held for construction 1,787,526 1,787,526 64,439 $ 13,471,645 $ 5,412,114 $ 195,102

Other Financial Assets (Tables)

Other Financial Assets (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Other Financial Assets	December 31 2020 2021 NT$ NT$ US$ (Note 4) Guarantee deposits $ 516,505 $ 1,007,651 $ 36,325 Pledged time deposits (Note 36) 367,550 415,065 14,963 Time deposits with original maturity over three months 35,988 60,499 2,181 Others (Note 36) 161,957 73,765 2,659 1,082,000 1,556,980 56,128 Current 551,655 140,857 5,078 Non-current $ 530,345 $ 1,416,123 $ 51,050

Investments Accounted for Usi_2

Investments Accounted for Using the Equity Method (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Investments Accounted for Using the Equity Method	December 31 2020 2021 NT$ NT$ US$ (Note 4) Investments in associates $ 12,335,239 $ 16,500,670 $ 594,833 Investments in joint ventures 471,434 495,930 17,878 $ 12,806,673 $ 16,996,600 $ 612,711
Summary of Investments in Associates Accounted for using the Equity Method	a. Investments in associates 1) Investments in associates accounted for using the equity method that was not individually material consisted of the following: Name of Associate Main Business Operating Location Carrying Amount as of December 31 2020 2021 NT$ NT$ US$ (Note 4) Yann Yuan Investment Co., Ltd. (“Yann Yuan”) Engaged in investing activities R.O.C. $ 6,670,035 $ 9,873,978 $ 355,947 ChipMOS Technologies Inc. (“ChipMOS”) Engaged in the packaging and testing of semiconductors R.O.C. 2,406,843 2,717,250 97,954 M-Universe Investment company Singapore 1,848,588 1,859,542 67,035 Hung Ching Development & Construction Co. (“HC”) Engaged in the development, construction and leasing of real estate properties R.O.C. 1,352,760 1,828,921 65,931 Hung Ching Kwan Co. (“HCK”) Engaged in the leasing of real estate properties R.O.C. 270,087 258,757 9,328 Chipletz, Inc. (“CHIPLETZ”) Fabless substrate design house U.S.A. — 210,937 7,604 Deca Technologies Inc. (”DECA”) Holding company with group engaged in the development of wafer level packaging and interconnect technology U.S.A. 87,075 51,434 1,854 12,635,388 16,800,819 605,653 Less: Deferred gain on transfer of land 300,149 300,149 10,820 $ 12,335,239 $ 16,500,670 $ 594,833 2) At each balance sheet date, the total percentages of ownership held by the Group were as follows: December 31 2020 2021 Yann Yuan 32.21 % 29.45 % ChipMOS 10.85 % 10.85 % MU 42.23 % 42.23 % HC 26.22 % 26.22 % HCK 27.31 % 27.31 % CHIPLETZ — 20.82 % DECA 17.85 % 17.85 %
Summary of Fair Values of Investments in Associates with Available Published Price Quotation	5) Fair values (Level 1) of investments in associates with available published price quotation are summarized as follows: December 31 2020 2021 NT$ NT$ US$ (Note 4) ChipMOS $ 2,710,572 $ 3,835,045 $ 138,250 HC $ 1,317,692 $ 2,141,249 $ 77,190
Summary of Aggregate Information of Associates that are Not Individually Material	6 Aggregate information of associates that are not individually material For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) The Group’s share of: Net i ncome $ 321,413 $ 545,833 $ 872,697 $ 31,460 Other comprehensive income 1,401,453 2,784,094 3,624,403 130,656 Total comprehensive income $ 1,722,866 $ 3,329,927 $ 4,497,100 $ 162,116
Summary Of Investments In Joint Ventures Accounted For Using The Equity Method And Summary Of Aggregate Information Of The Joint Venture That Is Not Individually Material	1) Investment in joint ventures Name of Joint Venture Main Business Operating Location Carrying Amount as of December 31 2020 2021 NT$ NT$ US$ (Note 4) SUMA-USI (“SUMA-USI”) Engaged in the design and manufacturing of electronic products China $ 471,434 $ 495,930 $ 17,878 2) At each balance sheet date, the percentages of ownership held by the Group’s subsidiary were as follows: December 31 2020 2021 SUMA-USI 49.00% 49.00% 4) Aggregate information of joint ventures that were not individually material For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) The Group’s share of: Net income $ (139,137 ) $ 1,780 $ 27,003 $ 973 Other comprehensive income (loss) (3,169 ) 3,881 — — Total comprehensive income (loss) $ (142,306 ) $ 5,661 $ 27,003 $ 973

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Property, Plant and Equipment	The carrying amounts of each class of property, plant and equipment were as follows: December 31 2020 (Retrospectively Adjusted) 2021 NT$ NT$ US$ (Note 4) Land $ 10,457,960 $ 11,530,540 $ 415,665 Buildings and improvements 82,813,857 79,273,937 2,857,748 Machinery and equipment 122,539,797 128,202,516 4,621,577 Other equipment 4,700,318 3,928,284 141,610 Construction in progress and machinery under insta llatio n 13,853,465 16,932,273 610,392 $ 234,365,397 $ 239,867,550 $ 8,646,992 For the year ended December 31, 2019 Land Buildings and Machinery and Other Construction in Total NT$ NT$ NT$ NT$ NT$ NT$ Cost Balance at January 1, 2019 $ 10,165,969 $ 141,708,011 $ 353,838,390 $ 18,380,122 $ 10,911,552 $ 535,004,044 Additions — 806,844 413,008 76,671 61,777,364 63,073,887 Disposals — (983,690 ) (19,139,634 ) (2,507,440 ) — (22,630,764 ) Reclassification — 13,601,469 41,302,651 3,062,838 (57,221,627 ) 745,331 Acquisition through business combinations (Note 29) 189,111 1,044,383 5,507,315 43,611 250,455 7,034,875 Effect of foreign currency exchange differences (21,258 ) (2,204,057 ) (5,176,282 ) (300,686 ) 919,817 (6,782,466 ) Balance at December 31, 2019 $ 10,333,822 $ 153,972,960 $ 376,745,448 $ 18,755,116 $ 16,637,561 $ 576,444,907 Accumulated depreciation and impairment Balance at January 1, 2019 $ — $ 62,744,074 $ 245,750,420 $ 12,194,041 $ — $ 320,688,535 Depreciation expenses — 6,989,392 35,747,308 2,503,967 — 45,240,667 Impairment losses recognized — 78,562 102,056 20,388 — 201,006 Disposals — (881,149 ) (18,640,266 ) (2,503,438 ) — (22,024,853 ) Reclassification — 210,558 83,777 (103 ) — 294,232 Acquisition through business combinations (Note 29) — 445,682 4,000,338 19,028 — 4,465,048 Effect of foreign currency exchange differences — (1,023,739 ) (3,294,855 ) (194,461 ) — (4,513,055 ) Balance at December 31, 2019 $ — $ 68,563,380 $ 263,748,778 $ 12,039,422 $ — $ 344,351,580 For the year ended December 31, 2020 (retrospectively adjusted) Land Buildings and Machinery and Other Construction in Total NT$ NT$ NT$ NT$ NT$ NT$ Cost Balance at January 1, 2020 $ 10,333,822 $ 153,972,960 $ 376,745,448 $ 18,755,116 $ 16,637,561 $ 576,444,907 Additions — 86,409 695,561 47,137 58,195,094 59,024,201 Disposals — (365,758 ) (12,818,849 ) (2,419,423 ) (126,605 ) (15,730,635 ) Disposal of subsidiaries (Note 30) — (3,665,811 ) (3,223,448 ) (445,506 ) (792,543 ) (8,127,308 ) Reclassification — 7,367,875 52,980,977 222,066 (60,032,844 ) 538,074 Acquisitions through business combinations (Note 29) 167,136 1,680,497 4,445,789 722,490 53,828 7,069,740 Effect of foreign currency exchange differences (42,998 ) (263,672 ) (2,456,999 ) (10,902 ) (81,026 ) (2,855,597 ) Balance at December 31, 2020 (retrospectively adjusted) $ 10,457,960 $ 158,812,500 $ 416,368,479 $ 16,870,978 $ 13,853,465 $ 616,363,382 Accumulated depreciation and impairment Balance at January 1, 2020 $ — $ 68,563,380 $ 263,748,778 $ 12,039,422 $ — $ 344,351,580 Depreciation expense — 7,401,223 36,373,712 2,241,613 — 46,016,548 Impairment losses recognized — — 981,535 10,738 — 992,273 Disposals — (300,832 ) (8,306,990 ) (2,398,756 ) — (11,006,578 ) Disposal of subsidiaries (Note 30) — (153,002 ) (345,834 ) (82,059 ) — (580,895 ) Reclassification — 3,462 497,230 (188,844 ) — 311,848 Acquisitions through business combinations (Note 29) — 548,190 3,049,895 588,935 — 4,187,020 Effect of foreign currency exchange differences — (63,778 ) (2,169,644 ) (40,389 ) — (2,273,811 ) Balance at December 31, 2020 $ — $ 75,998,643 $ 293,828,682 $ 12,170,660 $ — $ 381,997,985 For the year ended December 31, 2021 Land Buildings and Machinery Other Construction in under I Total NT$ NT$ NT$ NT$ NT$ NT$ Cost Balance at January 1, 2021 (retrospectively adjusted) $ 10,457,960 $ 158,812,500 $ 416,368,479 $ 16,870,978 $ 13,853,465 $ 616,363,382 Additions 1,126,012 2,718,507 1,332,497 135,439 69,105,086 74,417,541 Disposals (2,400 ) (659,833 ) (10,999,274 ) (2,144,766 ) (32,960 ) (13,839,233 ) Disposal of subsidiaries (Note 30) — (12,344,067 ) (33,309,236 ) (1,247,326 ) (1,237,431 ) (48,138,060 ) Reclassification 393 5,038,562 53,856,444 1,181,455 (64,884,288 ) (4,807,434 ) Acquisitions through business combinations (Note 29) — 5,284 28,282 3,108 4,852 41,526 Effect of foreign currency exchange differences (51,425 ) (929,254 ) (3,788,594 ) (197,844 ) 123,549 (4,843,568 ) Balance at December 31, 2021 $ 11,530,540 $ 152,641,699 $ 423,488,598 $ 14,601,044 $ 16,932,273 $ 619,194,154 Accumulated depreciation and impairment Balance at January 1, 2021 $ — $ 75,998,643 $ 293,828,682 $ 12,170,660 $ — $ 381,997,985 Depreciation expense — 7,620,561 39,147,076 1,836,523 — 48,604,160 Impairment losses recognized — 15,915 105,815 5,036 — 126,766 Disposals — (565,551 ) (10,151,428 ) (2,065,174 ) — (12,782,153 ) Disposal of subsidiaries (Note 30) — (5,369,867 ) (24,974,206 ) (1,100,858 ) — (31,444,931 ) Reclassification — (3,924,490 ) 142,234 (18,218 ) — (3,800,474 ) Acquisitions through business combinations (Note 29) — 241 1,067 2,452 — 3,760 Effect of foreign currency exchange differences — (407,690 ) (2,813,158 ) (157,661 ) — (3,378,509 ) Balance at December 31, 2021 $ — $ 73,367,762 $ 295,286,082 $ 10,672,760 $ — $ 379,326,604 Land Buildings and Machinery Other Construction in under I Total US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Cost Balance at January 1, 2021 ( re tr o spectively adjusted) $ 376,999 $ 5,725,036 $ 15,009,678 $ 608,182 $ 499,404 22,219,299 Additions 40,592 98,000 48,035 4,883 2,491,171 2,682,681 Disposals (86 ) (23,786 ) (396,513 ) (77,317 ) (1,188 ) (498,890 ) Disposal of subsidiaries (Note 30) — (444,992 ) (1,200,765 ) (44,965 ) (44,608 ) (1,735,330 ) Reclassification 14 181,635 1,941,473 42,590 (2,339,016 ) (173,304 ) Acquisitions through business combinations (Note 29) — 190 1,020 112 175 1,497 Effect of foreign currency exchange differences (1,854 ) (33,499 ) (136,575 ) (7,132 ) 4,454 (174,606 ) Balance at December 31, 2021 $ 415,665 $ 5,502,584 $ 15,266,353 $ 526,353 $ 610,392 $ 22,321,347 Accumulated depreciation and impairment Balance at January 1, 2021 $ — $ 2,739,677 $ 10,592,238 $ 438,740 $ — $ 13,770,655 Depreciation expense — 274,714 1,411,214 66,205 — 1,752,133 Impairment losses recognized — 574 3,815 182 — 4,571 Disposals — (20,388 ) (365,949 ) (74,447 ) — (460,784 ) Disposal of subsidiaries (Note 30) — (193,579 ) (900,296 ) (39,685 ) — (1,133,560 ) Reclassification — (141,474 ) 5,127 (657 ) — (137,004 ) Acquisitions through business combinations (Note 29) — 9 39 89 — 137 Effect of foreign currency exchange differences — (14,697 ) (101,412 ) (5,684 ) — (121,793 ) Balance at December 31, 2021 $ — $ 2,644,836 $ 10,644,776 $ 384,743 $ — $ 13,674,355
Summary of Property, Plant and Equipment Useful Lives	Each class of property, plant and equipment was depreciated on a straight-line basis over the following useful lives: Buildings and improvements Main plant buildings 10-55 years Cleanrooms 10-20 years Others 3-20 years Machinery and equipment 2-10 years Other equipment 2-20 years

Lease Arrangements (Tables)

Lease Arrangements (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Right-of-Use Assets	a. Right-of-use December 31 2020 (Retrospectively Adjusted) 2021 NT$ NT$ US$ (Note 4) Carrying amounts Land $ 5,961,974 $ 6,093,518 $ 219,666 Buildings and improvements 2,548,838 3,663,682 132,072 Machinery and equipment 181,065 880,443 31,739 Other equipment 49,930 42,619 1,536 $ 8,741,807 $ 10,680,262 $ 385,013 For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Additions to right-of-use $ 824,268 $ 702,996 $ 3,239,770 $ 116,791 Depreciation charge for right-of-use $ 215,301 $ 214,682 $ 217,674 $ 7,847 Land 307,708 370,458 509,746 18,376 Buildings and improvements Machinery and equipment 507,443 335,039 356,052 12,835 Other equipment 25,006 26,701 31,478 1,135 $ 1,055,458 $ 946,880 $ 1,114,950 $ 40,193
Summary of Lease Liabilities	b. Lease liabilities December 31 2020 2021 NT$ NT$ US$ (Note 4) Carrying amounts Current $ 774,444 $ 809,536 $ 29,183 Non-current $ 5,101,386 $ 6,590,348 $ 237,576
Summary of Land and Buildings Improvements	The Group’s lease liabilities were mainly from land and buildings and improvements. The range of discount rates for lease liabilities was as follows: December 31 2020 2021 Land (%) 0.54-8.00 0.54-8.00 Buildings and improvements (%) 0.54-8.84 0.45-8.84
Summary of Other Related Lease Information	e. Other lease information December 31 2020 2021 NT$ NT$ US$ (Note 4) Expenses relating to short-term leases $ 682,142 $ 814,235 $ 29,352 Expenses relating to low-value $ 5,433 $ 5,080 $ 183 Expenses relating to variable lease payments not included in the measurement of lease liabilities $ 43,112 $ 61,141 $ 2,204 Total cash outflow for leases $ 1,854,456 $ 2,909,157 $ 104,872

Investment Properties (Tables)

Investment Properties (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Investment Properties	For the year ended December 31, 2019 Land Buildings and Right-of-use Total NT$ NT$ NT$ NT$ Cost Balance at January 1, 2019 $ 35,965 $ 8,409,790 $ 6,891,947 $ 15,337,702 Additions — 2,532 — 2,532 Disposals — (1,843 ) — (1,843 ) Reclassification — (490,130 ) (21,069 ) (511,199 ) Effects of foreign currency exchange differences — (209,980 ) (303,086 ) (513,066 ) Balance at December 31, 2019 $ 35,965 $ 7,710,369 $ 6,567,792 $ 14,314,126 Accumulated depreciation Balance at January 1, 2019 $ — $ 707,376 $ 292,722 $ 1,000,098 Depreciation expenses — 377,536 216,574 594,110 Disposals — (1,240 ) — (1,240 ) Reclassification — (210,455 ) 543 (209,912 ) Effects of foreign currency exchange differences — 99,354 (22,355 ) 76,999 Balance at December 31, 2019 $ — $ 972,571 $ 487,484 $ 1,460,055 Carrying amount at December 31, 2019 $ 35,965 $ 6,737,798 $ 6,080,308 $ 12,854,071 For the year ended December 31, 2020 Land Buildings and Right-of-use Total NT$ NT$ NT$ NT$ Cost Balance at January 1, 2020 $ 35,965 $ 7,710,369 $ 6,567,792 $ 14,314,126 Additions — 6,352 — 6,352 Disposals — (1,902 ) — (1,902 ) Reclassification — (3,884 ) 46,201 42,317 Effects of foreign currency exchange differences — 111,870 124,920 236,790 Balance at December 31, 2020 $ 35,965 $ 7,822,805 $ 6,738,913 $ 14,597,683 Accumulated depreciation Balance at January 1, 2020 $ — $ 972,571 $ 487,484 $ 1,460,055 Depreciation expenses — 353,048 209,212 562,260 Disposals — (1,293 ) — (1,293 ) Reclassification — (1,498 ) 10,617 9,119 Effects of foreign currency exchange differences — 19,639 9,820 29,459 Balance at December 31, 2020 $ — $ 1,342,467 $ 717,133 $ 2,059,600 Carrying amount at December 31, 2020 $ 35,965 $ 6,480,338 $ 6,021,780 $ 12,538,083 For the year ended December 31, 2021 Land Buildings and Right-of-use Total NT$ NT$ NT$ NT$ Cost Balance at January 1, 2021 $ 35,965 $ 7,822,805 $ 6,738,913 $ 14,597,683 Disposals — (5,350 ) — (5,350 ) Disposal of subsidiaries (Note 30) — (1,290,187 ) (87,412 ) (1,377,599 ) Reclassification (Note 12) (393 ) 9,818,133 3,398,139 13,215,879 Effects of foreign currency exchange differences 0 30,697 (6,962 ) 23,735 Balance at December 31, 2021 $ 35,572 $ 16,376,098 $ 10,042,678 $ 26,454,348 Accumulated depreciation Balance at January 1, 2021 $ — $ 1,342,467 $ 717,133 $ 2,059,600 Depreciation expenses — 482,625 268,422 751,047 Disposals — (3,671 ) — (3,671 ) Disposal of subsidiaries (Note 30) — (570,403 ) (19,946 ) (590,349 ) Reclassification — 2,014,201 78,914 2,093,115 Effects of foreign currency exchange differences — 6,927 (7,108 ) (181 ) Balance at December 31, 2021 $ — $ 3,272,146 $ 1,037,415 $ 4,309,561 Carrying amount at December 31, 2021 $ 35,572 $ 13,103,952 $ 9,005,263 $ 22,144,787 Land Buildings and Right-of-use Total US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Cost Balance at January 1, 2021 $ 1,296 $ 282,005 $ 242,931 $ 526,232 Disposals — (193 ) — (193 ) Disposal of subsidiaries (Note 30) — (46,510 ) (3,151 ) (49,661 ) Reclassification (Note 12) (14 ) 353,934 122,500 476,420 Effects of foreign currency exchange differences — 1,107 (251 ) 856 Balance at December 31, 2021 $ 1,282 $ 590,343 $ 362,029 $ 953,654 Accumulated depreciation Balance at January 1, 2021 $ — $ 48,395 $ 25,852 $ 74,247 Depreciation expenses — 17,398 9,676 27,074 Disposals — (132 ) — (132 ) Disposal of subsidiaries (Note 30) — (20,563 ) (719 ) (21,282 ) Reclassification — 72,610 2,845 75,455 Effects of foreign currency exchange differences — 250 (256 ) (6 ) Balance at December 31, 2021 $ — $ 117,958 $ 37,398 $ 155,356 Carrying amount at December 31, 2021 $ 1,282 $ 472,385 $ 324,631 $ 798,298
Summary of Maturity analysis of Operating Lease Payments	The maturity analysis of lease payments receivable under operating leases of investment properties was as follows: December 31 2020 2021 NT$ NT$ US$ (Note 4) Year 1 $ 880,929 $ 1,693,659 $ 61,055 Year 2 688,123 1,405,450 50,666 Year 3 471,966 1,210,891 43,651 Year 4 383,307 1,019,498 36,752 Year 5 335,706 929,609 33,511 Year 6 onwards 664,259 3,241,525 116,854 $ 3,424,290 $ 9,500,632 $ 342,489
Summary of Investment Properties, Useful Lives	The investment properties were depreciated on a straight-line basis over the following useful lives: Main buildings 10-40 years Right-of-use 10-50 years
Summary of Investment Properties, Fair Value	The fair value of the investment properties was as follows: December 31 2020 2021 NT$ NT$ US$ (Note 4) Fair value $ 19,799,714 $ 36,158,216 $ 1,303,468

Goodwill (Tables)

Goodwill (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Goodwill	Cost Accumulated Carrying NT$ NT$ NT$ Balance at January 1, 2019 $ 52,388,559 $ 2,414,113 $ 49,974,446 Acquisition through business combinations (Note 29) 264,977 — 264,977 Effect of foreign currency exchange differences (40,987 ) — (40,987 ) Balance at December 31, 2019 $ 52,612,549 $ 2,414,113 $ 50,198,436 For the year ended December 31, 2020 (retrospectively adjusted) Cost Accumulated Carrying NT$ NT$ NT$ Balance at January 1, 2020 $ 52,612,549 $ 2,414,113 $ 50,198,436 Acquisition through business combinations (Note 29) 2,567,842 — 2,567,842 Effect of foreign currency exchange differences (57,225 ) — (57,225 ) Balance at December 31, 2020 $ 55,123,166 $ 2,414,113 $ 52,709,053 For the year ended December 31, 2021 Cost Accumulated Carrying NT$ NT$ NT$ Balance at January 1, 2021 (retrospectively adjusted) $ 55,123,166 $ 2,414,113 $ 52,709,053 Disposal of subsidiaries (Note 30) (310,711 ) — (310,711 ) Effect of foreign currency exchange differences (325,929 ) — (325,929 ) Balance at December 31, 2021 $ 54,486,526 $ 2,414,113 $ 52,072,413 Cost Accumulated Carrying US$ (Note 4) US$ (Note 4) US$ (Note 4) Balance at January 1, 2021 (re tro adjusted) $ 1,987,136 $ 87,026 $ 1,900,110 Disposal of subsidiaries (Note 30) (11,201 ) — (11,201 ) Effect of foreign currency exchange differences (11,749 ) — (11,749 ) Balance at December 31, 2021 $ 1,964,186 $ 87,026 $ 1,877,160
Summary of Carrying Amounts of Goodwill Allocated to Cash-generating Units	December 31 2020 (Retrospectively 2021 Cash-generating units NT$ NT$ US$ (Note 4) Packaging segment $ 35,703,625 $ 35,412,424 $ 1,276,583 Testing segment 13,365,068 13,304,040 479,598 EMS segment (Note 29) 3,492,259 3,207,848 115,640 Others 148,101 148,101 5,339 $ 52,709,053 $ 52,072,413 $ 1,877,160

Other Intangible Assets (Tables

Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Carrying Amounts of Each Class of Other Intangible Assets	The carrying amounts of each class of other intangible assets were as follows: December 31 2020 (Retrospectively Adjusted) 2021 NT$ NT$ US$ (Note 4) Customer relationships $ 9,120,300 $ 7,990,956 $ 288,066 Computer software 2,795,873 2,779,723 100,206 Patents and acquired specific technology 15,720,213 13,730,404 494,968 Others 75,385 62,624 2,258 $ 27,711,771 $ 24,563,707 $ 885,498 For the year ended December 31, 2019 Customer Computer Patents and Others Total NT$ NT$ NT$ NT$ NT$ Cost Balance at January 1, 2019 $ 11,915,636 $ 4,401,045 $ 20,588,356 $ 83,657 $ 36,988,694 Additions — 1,358,533 — (7,625 ) 1,350,908 Disposals or derec o tion (915,635 ) (1,123,446 ) — (6,315 ) (2,045,396 ) Acquisition through business combinations (Note 29) — 19,944 732,604 — 752,548 Effect of foreign currency exchange differences — (49,198 ) (2,264 ) (1,417 ) (52,879 ) Balance at December 31, 2019 $ 11,000,001 $ 4,606,878 $ 21,318,696 $ 68,300 $ 36,993,875 Accumulated amortization Balance at January 1, 2019 $ 1,548,839 $ 3,241,363 $ 1,332,687 $ 27,772 $ 6,150,661 Amortization expense 1,033,464 583,300 1,955,703 4,139 3,576,606 Disposals or derecognization (915,635 ) (1,116,512 ) — (6,315 ) (2,038,462 ) Acquisition through business combinations (Note 29) — 7,765 313,422 — 321,187 Effect of foreign currency exchange differences — (38,577 ) (1,639 ) (293 ) (40,509 ) Balance at December 31, 2019 $ 1,666,668 $ 2,677,339 $ 3,600,173 $ 25,303 $ 7,969,483 For the year ended December 31, 2020 (retrospectively adjusted) Customer Computer Patents and Others Total NT$ NT$ NT$ NT$ NT$ Cost Balance at January 1, 2020 $ 11,000,001 $ 4,606,878 $ 21,318,696 $ 68,300 $ 36,993,875 Additions — 951,439 171 31,045 982,655 Disposals or derecognization — (55,413 ) — (14,594 ) (70,007 ) Disposal of subsidiaries (Note 30) — (38,125 ) — — (38,125 ) Acquisition through business combinations (Note 29) 885,565 1,567,508 — 114,269 2,567,342 Effect of foreign currency exchange differences 4,717 (65,838 ) 312 (19,160 ) (79,969 ) Balance at December 31, 2020 $ 11,890,283 $ 6,966,449 $ 21,319,179 $ 179,860 $ 40,355,771 Accumulated amortization Balance at January 1, 2020 $ 1,666,668 $ 2,677,339 $ 3,600,173 $ 25,303 $ 7,969,483 Amortization expense 1,000,000 729,330 1,998,554 5,493 3,733,377 Disposals or derecognization — (47,345 ) — (5,044 ) (52,389 ) Disposal of subsidiaries (Note 30) — (10,688 ) — — (10,688 ) Acquisition through business combinations (Note 29) 102,768 843,746 — 79,673 1,026,187 Effect of foreign currency exchange differences 547 (21,806 ) 239 (950 ) (21,970 ) Balance at December 31, 2020 $ 2,769,983 $ 4,170,576 $ 5,598,966 $ 104,475 $ 12,644,000 For the year ended December 31, 2021 Customer Computer Patents and Others Total NT$ NT$ NT$ NT$ NT$ Cost Balance at January 1, 2021 (retrospectively adjusted) $ 11,890,283 $ 6,966,449 $ 21,319,179 $ 179,860 $ 40,355,771 Additions — 1,193,060 2,000 37,959 1,233,019 Disposals or derecognization (102,637 ) (150,670 ) — (71,014 ) (324,321 ) Disposal of subsidiaries (Note 30) — (789,998 ) (5,401 ) (6,243 ) (801,642 ) Acquisition through business combinations (Note 29) — 622 — — 622 Effect of foreign currency exchange differences (83,041 ) (167,769 ) (537 ) (7,036 ) (258,383 ) Balance at December 31, 2021 $ 11,704,605 $ 7,051,694 $ 21,315,241 $ 133,526 $ 40,205,066 Accumulated amortization Balance at January 1, 2021 $ 2,769,983 $ 4,170,576 $ 5,598,966 $ 104,475 $ 12,644,000 Amortization expense 1,049,759 971,190 1,991,641 41,530 4,054,120 Disposals or derecognization (102,637 ) (139,907 ) — (67,741 ) (310,285 ) Disposal of subsidiaries (Note 30) — (626,338 ) (5,288 ) (3,067 ) (634,693 ) Acquisition through business combinations (Note 29) — 222 — — 222 Effect of foreign currency exchange differences (3,456 ) (103,772 ) (482 ) (4,295 ) (112,005 ) Balance at December 31, 2021 $ 3,713,649 $ 4,271,971 $ 7,584,837 $ 70,902 $ 15,641,359 Customer Computer Patents and Others Total US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Cost Balance at January 1, 2021 (retrospectively adjusted) $ 428,633 $ 251,134 $ 768,536 $ 6,484 $ 1,454,787 Additions — 43,009 72 1,368 44,449 Disposals or derecognization (3,700 ) (5,432 ) — (2,560 ) (11,692 ) Disposal of subsidiaries (Note 30) — (28,479 ) (195 ) (225 ) (28,899 ) Acquisition through business combinations (Note 29) — 23 — — 23 Effect of foreign currency exchange differences (2,994 ) (6,048 ) (19 ) (254 ) (9,315 ) Balance at December 31, 2021 $ 421,939 $ 254,207 $ 768,394 $ 4,813 $ 1,449,353 Accumulated amortization Balance at January 1, 2021 $ 99,855 $ 150,345 $ 201,837 $ 3,766 $ 455,803 Amortization expense 37,843 35,010 71,797 1,497 146,147 Disposals or derecognization (3,700 ) (5,043 ) — (2,442 ) (11,185 ) Disposal of subsidiaries (Note 30) — (22,579 ) (191 ) (110 ) (22,880 ) Acquisition through business combinations (Note 29) — 8 — — 8 Effect of foreign currency exchange differences (125 ) (3,741 ) (17 ) (155 ) (4,038 ) Balance at December 31, 2021 $ 133,873 $ 154,000 $ 273,426 $ 2,556 $ 563,855
Summary of Other Intangible Assets Useful Lives	Each class of other intangible assets was amortized on the straight-line basis over the following useful lives: December 31, December 31, 2021 Customer relationships 11-16 years 11-16 years Computer software 2-10 years 2-10 years Patents and acquired specific technology 5-17 years 5-17 years Others 5-32 years 5-10 years

Borrowings (Tables)

Borrowings (Tables)	12 Months Ended
	Dec. 31, 2021
Short Term Bank Loans [member]
Statement [LineItems]
Summary of Borrowings	a. Short-term borrowings Bank loans mainly represented unsecured revolving loans , a nd bank overdrafts. December 31 2020 2021 NT$ NT$ US$ (Note 4) Secured bank loans, annual interest rates both were 0.90%-1.87% as of December 31, 2020 and 2021 $ 300,495 $ 203,127 $ 7,322 Unsecured bank loans, annual interest rates were 0.58%-3.38% 0.40%-3.75% 34,297,362 40,833,302 1,472,001 34,597,857 41,036,429 1,479,323 Less: financial liabilities for hedging - current (Note 34) 3,307,018 6,716,965 242,140 $ 31,290,839 $ 34,319,464 $ 1,237,183
Long Term Bank Loans [member]
Statement [LineItems]
Summary of Borrowings	b. Long-term borrowings 1) Bank loans December 31 2020 2021 NT$ NT$ US$ (Note 4) Revolving bank loans Syndicated bank loans - repayable through January 2022, annual interest rates were 1.15%-1.17% and 1.08% as of December 31, 2020 and 2021, respectively (Note 36) $ 12,536,424 $ 2,562,926 $ 92,391 Others - repayable through January 2022 to July 2029, annual interest rates were 0.56%-4.15% and 0.40%-4.00% as of December 31, 2020 and 2021, respectively 84,146,125 107,383,417 3,871,068 Mortgage loans Repayable through March 2022 to December 2033, annual interest rates were 1.90%-4.90% and 2.32%-4.55% as of December 31, 2020 and 2021, respectively 10,813,997 8,031,142 289,515 107,496,546 117,977,485 4,252,974 Less: unamortized discounts 104,323 3,642 131 107,392,223 117,973,843 4,252,843 Less: current portion 2,250,121 4,526,683 163,183 financial liabilities for hedging - current (Note 34) 1,970,307 — — financial liabilities for hedging - non-current (Note 34) 5,910,919 4,780,931 172,348 $ 97,260,876 $ 108,666,229 $ 3,917,312
Longterm Bills Payable [member]
Statement [LineItems]
Summary of Borrowings	2) Long-term bills payable December 31 2020 2021 NT$ NT$ US$ (Note 4) China Bills Finance Corporation, repayable through March 2023 to December 2023, annual interest rates were 0.65%-0.90% and 0.65% as of December 31, 2020 and 2021, respectively $ 2,000,000 $ 2,500,000 $ 90,123 December 31 2020 2021 NT$ NT$ US$ (Note 4) Ta Ching Bills Finance Corporation, repayable through January 2023 to March 2023, annual interest rates were 0.91% and 0.65% as of December 31, 2020 and 2021, respectively $ 1,000,000 $ 2,500,000 $ 90,123 Mega Bills Finance Corporation, repayable in March 2023, annual interest rates were 0.92%-0.93% and 0.65% as of December 31, 2020 and 2021, respectively 2,000,000 2,000,000 72,098 International Bills Finance Corporation, early repaid in March 2023, annual interest rate was 0.65% as of December 31, 2021 — 1,500,000 54,073 5,000,000 8,500,000 306,417 Less: unamortized discounts 1,498 1,353 49 $ 4,998,502 $ 8,498,647 $ 306,368

Bonds Payable (Tables)

Bonds Payable (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Bonds Payable	December 31 2020 2021 NT$ NT$ US$ (Note 4) Unsecured domestic bonds Interest due annually with annual interest rate at 1.30% and fully redeemed in January 2021 $ 7,000,000 $ — $ — Repayable at maturity in January 2023 and interest due annually with annual interest rate at 1.50% 2,000,000 2,000,000 72,098 Repayable at maturity in January 2022 and interest due annually with annual interest rate at 1.25% 3,700,000 3,700,000 133,381 Repayable at maturity in January 2024 and interest due annually with annual interest rate at 1.45% 4,300,000 4,300,000 155,011 Repayable at maturity in April 2024 and interest due annually with annual interest rate at 0.90% 6,500,000 6,500,000 234,319 Repayable at maturity in April 2026 and interest due annually with annual interest rate at 1.03% 3,500,000 3,500,000 126,172 Repayable at maturity in April 2025 and interest due annually with annual interest rate at 0.90% 10,000,000 10,000,000 360,490 Repayable at maturity in August 2023 and interest due annually with annual interest rate at 0.72% 3,000,000 3,000,000 108,147 Repayable at maturity in August 2025 and interest due annually with annual interest rate at 0.85% 5,000,000 5,000,000 180,245 Repayable at maturity in August 2027 and interest due annually with annual interest rate at 0.95% 2,000,000 2,000,000 72,098 Unsecured overseas bonds US$200,000 thousand (linked to New Taiwan dollar), repayable at maturity in October 2022 and interest due quarterly with annual interest rate at 2.15% 6,204,800 6,204,800 223,677 US$100,000 thousand (linked to New Taiwan dollar), repayable at maturity in October 2024 and interest due quarterly with annual interest rate at 2.50% 3,102,400 3,102,400 111,839 Unsecured overseas convertible bonds RMB779,801 thousand, repayable at maturity in March 2027 and interest due annually with annual interest rate at 0.10%, 0.20%, 0.60%, 1.30%, 1.80% and 2.00% for the first, second, third, fourth, fifth and sixth year, respectively — 3,385,381 122,040 56,307,200 52,692,581 1,899,517 Less: discounts on bonds payable 53,646 425,244 15,330 56,253,554 52,267,337 1,884,187 Less: current portion of bonds payable 6,999,951 9,902,710 356,983 $ 49,253,603 $ 42,364,627 $ 1,527,204

Other Payables (Tables)

Other Payables (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Other Payables	December 31 2020 2021 NT$ NT$ US$ (Note 4) Payables for property, plant and equipment $ 10,013,971 $ 13,607,664 $ 490,543 Accrued salary and bonus 12,448,548 12,217,011 440,411 Accrued employees’ compensation and remuneration to directors 4,405,981 7,711,445 277,990 Accrued employee insurance 1,105,122 1,204,387 43,417 Accrued utilities 536,491 581,662 20,968 Others 10,905,510 11,374,731 410,049 $ 39,415,623 $ 46,696,900 $ 1,683,378

Retirement Benefit Plans (Table

Retirement Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Defined Benefit Plans Amounts Included in Consolidated Balance Sheets	The amounts included in the consolidated balance sheets arising from the Group’s obligation in respect of its defined benefit plans excluding those for executive managers were as follows: December 31 2020 2021 NT$ NT$ US$ (Note 4) Present value of the defined benefit obligation $ 12,159,145 $ 11,424,860 $ 411,855 Fair value of the plan assets (5,962,305 ) (5,863,264 ) (211,365 ) Present value of unfunded defined benefit obligation 6,196,840 5,561,596 200,490 Recorded under other payables (102,367 ) (67,524 ) (2,434 ) Recorded under other non-current 26,306 — — Net defined benefit liabilit ies $ 6,120,779 $ 5,494,072 $ 198,056
Summary of Movements in Net Defined Benefit Liability (Asset)	Movements in net defined benefit liabilit ies Present Value of the Defined Fair Value of Net Defined Liabilit ies s NT$ NT$ NT$ Balance at January 1, 2019 $ 10,297,139 $ (5,492,123 ) $ 4,805,016 Service cost Current service cost 211,226 — 211,226 Net interest expense (income) 151,635 (97,387 ) 54,248 Recognized in profit or loss 362,861 (97,387 ) 265,474 Remeasurement Return on plan assets (excluding amounts included in net interest) — (104,516 ) (104,516 ) Actuarial (gain) loss Changes in financial assumptions 398,732 — 398,732 Experience adjustments 70,374 — 70,374 Changes in demographic assumptions (2,329 ) — (2,329 ) Recognized in other comprehensive income 466,777 (104,516 ) 362,261 Contributions from the employer — (514,617 ) (514,617 ) Benefits paid from the pension fund (393,897 ) 393,897 — the Group (21,439 ) — (21,439 ) Business combinations 62,857 (28,380 ) 34,477 Exchange differences on foreign plans (105,724 ) 100,948 (4,776 ) Balance at December 31, 2019 10,668,574 (5,742,178 ) 4,926,396 Service cost Current service cost 193,693 — 193,693 Past service cost and gain on settlements (25,891 ) — (25,891 ) Net interest expense (income) 119,314 (81,114 ) 38,200 Recognized in profit or loss 287,116 (81,114 ) 206,002 Remeasurement Return on plan assets (excluding amounts included in net interest) — (109,616 ) (109,616 ) Actuarial (gain) loss Changes in financial assumptions 465,433 — 465,433 Experience adjustments 281,661 — 281,661 Changes in demographic assumptions (36,627 ) — (36,627 ) Recognized in other comprehensive income 710,467 (109,616 ) 600,851 Present Value of the Defined Fair Value of Net Defined Liabilit ies s NT$ NT$ NT$ Contributions from the employer $ — $ (620,433 ) $ (620,433 ) Benefits paid from the pension fund (552,430 ) 603,137 50,707 the Group (14,520 ) — (14,520 ) Assets extinguished on settlement — 11,910 11,910 Business combinations 1,018,480 — 1,018,480 Exchange differences on foreign plans 41,458 (24,011 ) 17,447 Balance at December 31, 2020 12,159,145 (5,962,305 ) 6,196,840 Service cost Current service cost 173,307 — 173,307 Past service cost and gain on settlements (10,284 ) — (10,284 ) Net interest expense (income) 78,501 (59,761 ) 18,740 Recognized in profit or loss 241,524 (59,761 ) 181,763 Remeasurement Return on plan assets (excluding amounts included in net interest) — (42,636 ) (42,636 ) Actuarial (gain) loss Changes in financial assumptions (418,542 ) — (418,542 ) Experience adjustments 242,896 — 242,896 Changes in demographic assumptions 160,156 — 160,156 Recognized in other comprehensive income (15,490 ) (42,636 ) (58,126 ) Contributions from the employer — (542,584 ) (542,584 ) Benefits paid from the pension fund (556,419 ) 562,442 6,023 the Group (80,603 ) — (80,603 ) Business combinations 46,291 — 46,291 Exchange differences on foreign plans (369,588 ) 181,580 (188,008 ) Balance at December 31, 2021 $ 11,424,860 $ (5,863,264 ) $ 5,561,596 Present Value of the Defined Fair Value of Net Defined Liabilit ies s US$ (Note 4) US$ (Note 4) US$ (Note 4) Balance at January 1, 2021 $ 438,325 $ (214,935 ) $ 223,390 Service cost Current service cost 6,248 — 6,248 Past service cost and gain on settlements (371 ) — (371 ) Net interest expense (income) 2,830 (2,154 ) 676 Recognized in profit or loss 8,707 (2,154 ) 6,553 Remeasurement Return on plan assets (excluding amounts included in net interest) — (1,537 ) (1,537 ) Actuarial (gain) loss Changes in financial assumptions (15,088 ) — (15,088 ) Experience adjustments 8,756 — 8,756 Changes in demographic assumptions 5,773 — 5,773 Recognized in other comprehensive income (559 ) (1,537 ) (2,096 ) Contributions from the employer — (19,560 ) (19,560 ) Benefits paid from the pension fund (20,058 ) 20,275 217 the Group (2,906 ) — (2,906 ) Business combinations 1,669 — 1,669 Exchange differences on foreign plans (13,323 ) 6,546 (6,777 ) Balance at December 31, 2021 $ 411,855 $ (211,365 ) $ 200,490
Summary of Fair Value of the Plan Assets by Major Categories	The fair value of the plan assets by major categories at each balance sheet date was as follows: December 31 2020 2021 NT$ NT$ US$ (Note 4) Cash $ 2,236,340 $ 2,267,223 $ 81,731 Equity instruments 2,459,708 2,334,180 84,145 Debt instruments 1,092,115 1,039,412 37,470 Others 174,142 222,449 8,019 Total $ 5,962,305 $ 5,863,264 $ 211,365
Summary of Key Assumptions Used for the Actuarial Valuations	Except the pension plans for executive managers, the key assumptions used for the actuarial valuations were as follow: December 31 2020 2021 Discount rates (%) 0.00-2.77 0.05-3.31 Expected rates of salary increase (%) 1.00-4.06 1.00-4.02
Summary of Sensitivity Analysis on Defined Obligations	December 31 2020 2021 NT$ NT$ US$ (Note 4) Discount rate 0.5% higher $ (617,803 ) $ (548,265 ) $ (19,764 ) 0.5% lower $ 600,451 $ 593,980 $ 21,412 Expected rates of salary increase 0.5% higher $ 611,217 $ 538,689 $ 19,419 0.5% lower $ (565,555 ) $ (503,700 ) $ (18,158 )
Summary of Maturity Analysis of Undiscounted Pension Benefit	Maturity analysis of undiscounted pension benefit December 31 2020 2021 NT$ NT$ US$ (Note 4) No later than 1 year $ 498,092 $ 561,812 $ 20,253 Later than 1 year but not later than 5 years 2,553,522 2,593,560 93,495 Later than 5 years 12,325,576 12,600,192 454,225 $ 15,377,190 $ 15,755,564 $ 567,973

Equity (Tables)

Equity (Tables)	12 Months Ended
	Dec. 31, 2021
Statement [LineItems]
Summary of Share Capital	a. Share capital Ordinary shares December 31 2020 2021 Numbers of shares authorized (in thousands) 5,500,000 5,500,000 Numbers of shares reserved (in thousands) Employee share options 400,000 400,000 Number of shares issued and fully paid (in thousands) 4,351,592 4,408,650 December 31 2020 2021 NT$ NT$ US$ (Note 4) Share capital authorized $ 55,000,000 $ 55,000,000 $ 1,982,696 Share capital reserved Employee share options $ 4,000,000 $ 4,000,000 $ 144,196 American Depositary Receipts
Summary of Capital Surplus	b. Capital surplus December 31 2020 2021 NT$ NT$ US$ (Note 4) May be used to offset a deficit, distributed as cash dividends, or transferred to share capital (1) Issuance of ordinary shares $ 13,548,426 $ 16,049,286 $ 578,561 Merger by share exchange 117,693,658 117,693,658 4,242,742 Difference between consideration and the carrying amount of the subsidiaries’ net assets during actual disposal or acquisition 3,240,987 3,240,987 116,835 Exercised employee share options 1,617,254 2,362,951 85,182 Treasury share transactions 510,449 816,186 29,422 Expired share options (Note 28) 645,903 645,903 23,284 137,256,677 140,808,971 5,076,026 May be used to offset a deficit only Changes in percentage of ownership interest in subsidiaries (2) 1,451 1,451 52 Share of changes in capital surplus of associates 41,239 10,706 386 Dividends that the claim period has elapsed and unclaimed by shareholders 3,550 5,183 187 46,240 17,340 625 May not be used for any purpose Employee share options 1,894,952 1,442,132 51,988 Employee restricted stock awards — 1,193,782 43,034 Others (3) 569,681 230,943 8,326 2,464,633 2,866,857 103,348 $ 139,767,550 $ 143,693,168 $ 5,179,999 1) Such capital surplus may be used to offset a deficit; in addition, when the Company has no deficit, such capital surplus may be distributed as cash dividends or transferred to share capital (limited to a certain percentage of the Company’s capital surplus and once a year). 2) Such capital surplus arises from the effects of changes in ownership interests in subsidiaries resulting from equity transactions other than actual disposals or acquisitions, or from changes in capital surplus of subsidiaries accounted for using the equity method. 3) Such capital surplus represents the excess of the carrying amount of related accounts over the par value due to employee share options exercised and the Company has not completed registration formalities.
Disclosure of Detailed Information About Appropriation of Retained Earnings Explanatory	The appropriation of earnings for 2019 and 2020 resolved in , Appropriation of Earnings Dividends Per Share For Year 2019 For Year 2020 For Year 2019 For Year 2020 NT$ NT$ NT$ NT$ (in dollars) (in dollars) Legal reserve $ 1,697,489 $ 2,398,814 Special reserve (reverse) 3,944,915 (1,278,670 ) Cash dividends 8,668,331 18,389,856 $ 2.0 $ 4.2 $ 14,310,735 $ 19,510,000
Summary of Unrealized Gain (Loss) on Financial Assets at FVTOCI	2) Unr e For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Balance at January 1 $ (1,015,107 ) $ (203,098 ) $ 2,027,902 $ 73,104 Unrealized gain (loss) recognized during the year Debt instruments (2,052 ) (2,136 ) 63,722 2,297 Equity instruments (283,472 ) (405,020 ) (8,671 ) (313 ) Share from associates and joint venture accounted for using the equity method 1,501,689 2,655,570 3,599,703 129,766 Realized gain (loss) recognized during the year Disposal of associates and joint venture accounted for using the equity method — 1,094 — — Cumulative unrealized loss of equity instruments transferred to retained earnings due to disposal — 16,383 33,258 1,199 Cumulative unrealized loss transferred to retained earnings due to disposal of equity instruments in relation to associates and joint venture accounted for using the equity method (404,156 ) (34,891 ) (1,525,553 ) (54,995 ) Balance at December 31 $ (203,098 ) $ 2,027,902 $ 4,190,361 $ 151,058
Schedule of detailed information about hedges of net investments of foreign operations	3) Gain (loss) on hedging instruments - For the Year Ended December 31 2020 2021 NT$ NT$ US$ (Note 4) Balance at January 1 $ — $ (429,265 ) $ (15,475 ) Recognized during the year Foreign currency risk – loans denominated in foreign currency (429,265 ) 551,098 19,867 Balance at December 31 $ (429,265 ) $ 121,833 $ 4,392
Summary of Unearned Employee Compensation	In August 2021, the shareholders’ meeting resolved to issue restricted stock awards for employees . R For the Year Ended NT$ US$ (Note 4) Balance at January 1 $ — $ — Issuance of employee restricted stock awards (1,343,782 ) (48,442 ) Share-based payment expenses 178,791 6,446 Balance at December 31 $ (1,164,991 ) $ (41,996 )
Summary of Treasury Shares	e. Treasury shares (in thousand shares) Purpose of Repurchase Shares Shares held by Total Balance at December 31, 2020 — 72,941 72,941 Balance at January 1, 2021 — 72,941 72,941 Addition 53,067 — 53,067 Balance at December 31, 2021 53,067 72,941 126,008
Summary of Shares Held By Subsidiaries	The Company’s shares held by its subsidiaries at each balance sheet date were as follows: Shares Held by Carrying Carrying Fair Value Fair Value (in thousand NT$ US$ (Note 4) NT$ US$ (Note 4) December 31, 2020 ASE Test 44,100 $ 1,380,721 $ 3,585,349 J&R Holding 23,352 381,709 1,898,508 ASE Test, Inc. 5,489 196,677 446,287 72,941 $ 1,959,107 $ 5,930,144 December 31, 2021 ASE Test 44,100 $ 1,380,721 $ 49,774 $ 4,696,675 $ 169,311 J&R Holding 23,352 381,709 13,760 2,486,975 89,653 ASE Test, Inc. 5,489 196,677 7,090 584,620 21,075 72,941 $ 1,959,107 $ 70,624 $ 7,768,270 $ 280,039
Summary of Non-controlling Interests	f. Non-controlling For the Year Ended December 31 2019 2020 (retrospectively 2021 NT$ NT$ NT$ US$ (Note 4) Balance at January 1 (retrospectively adjusted) $ 17,639,487 $ 13,374,912 $ 15,622,009 $ 563,158 Share of profit for the year 1,207,974 1,681,320 2,099,830 75,697 Other comprehensive income (loss) for the year Exchange difference on translating foreign operations (414,010 ) 178,480 (321,551 ) (11,592 ) Unrealized gain (10,773 ) 1,321 50,679 1,827 Gain (loss) — (145,559 ) 187,502 6,759 Remeasurement on defined benefit plans (7,422 ) (9,075 ) 1,497 54 Share of from — — 7,902 285 Non-controlling 666,651 298 — — Acquisition of non-controlling (5,084,785 ) (116,738 ) — — Issuance of ordinary shares by subsidiaries (Note 29) 83,044 1,711,453 — — Subsidiaries’ buy back of their own outstanding ordinary shares (Note 31) (2,017,319 ) (2,299,533 ) (2,748,521 ) (99,081 ) Equity component of convertible bonds issued by subsidiaries — — 393,199 14,174 Non-controlling 1,672,310 1,591,904 314,398 11,334 Cash dividends d ist ri buted non-controlling (360,245 ) (346,774 ) (1,062,529 ) (38,303 ) Balance at December 31 $ 13,374,912 $ 15,622,009 $ 14,544,415 $ 524,312
Exchange differences on translating foreign operations [member]
Statement [LineItems]
Summary of Other Reserves	1) Exchange differences on translating foreign operations For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Balance at January 1 $ (5,888,574 ) $ (10,762,684 ) $ (11,641,939 ) $ (419,681 ) Recognized for the year Exchange differences a ri ng (4,788,135 ) (1,173,204 ) (3,203,730 ) (115,491 ) Share from associates and joint venture accounted for using the equity method (85,975 ) 101,038 21,307 768 Reclassification Disposal of associates and joint venture accounted for using the equity method — 29,971 — — Disposal of foreign operations — 162,940 (569,284 ) (20,522 ) Balance at December 31 $ (10,762,684 ) $ (11,641,939 ) $ (15,393,646 ) $ (554,926 )

Profit Before Income Tax (Table

Profit Before Income Tax (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Other Operating Income and Expenses, Net	a. Other operating income and expenses, net For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Rental income $ 136,301 $ 153,682 $ 175,373 $ 6,322 Gain (loss) on disposal of property, plant and equipment (164,467 ) 460,868 71,770 2,587 Royalty income — — 135,400 4,881 Impairment loss (Note 15) (201,006 ) (992,273 ) (126,766 ) (4,571 ) Others (39,383 ) 880,215 934,052 33,673 $ (268,555 ) $ 502,492 $ 1,189,829 $ 42,892
Summary of Other Income	b. Other income For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Interest income Bank deposits $ 549,681 $ 520,783 $ 529,132 $ 19,074 Contracts with customers — — 13,197 476 Government subsidies 624,351 803,049 767,918 27,683 Dividends income 185,061 150,715 289,852 10,449 $ 1,359,093 $ 1,474,547 $ 1,600,099 $ 57,682
Summary of Other Gains, net	c. Other gains and losses For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Remeasurement gain on investments accounted for using the equity method due to step acquisition $ 319,712 $ — $ — $ — Net gain on financial assets mandatorily at FVTPL 3,631,763 3,211,125 1,199,065 43,225 Net loss arising on financial instruments held for trading (1,984,941 ) (3,282,973 ) (2,689,070 ) (96,938 ) Gain on disposal of subsidiaries (Note 30) — 802,753 17,340,418 625,105 Foreign exchange gain, net 1,125,681 1,005,374 1,395,054 50,290 Gain recognized in bargain purchase transaction (Note 29) — — 33,114 1,194 Gain (loss) on disposal of investments accounted for using the equity method — 91,297 (67,482 ) (2,433 ) Impairment loss on financial assets (400,201 ) — — — Others (8,025 ) — — — $ 2,683,989 $ 1,827,576 $ 17,211,099 $ 620,443
Summary of Finance Costs	d. Finance costs For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Interest on lease liabilities $ 88,742 $ 88,026 $ 105,159 $ 3,791 Interest on borrowings and bonds payable 4,211,541 3,498,999 2,790,368 100,590 Total interest expense for financial liabilities measured at amortized cost 4,300,283 3,587,025 2,895,527 104,381 Less: Amounts included in the cost of qualifying assets Inventories related to real estate business (35,713 ) (95,589 ) (71,011 ) (2,560 ) Property, plant and equipment (77,715 ) (54,208 ) (25,581 ) (922 ) 4,186,855 3,437,228 2,798,935 100,899 Other finance costs 16,540 22,283 32,372 1,167 $ 4,203,395 $ 3,459,511 $ 2,831,307 $ 102,066
Summary of Capitalized Borrowing Costs	Information relating to the capitalized borrowing costs was as follows: For the Year Ended December 31 2019 2020 2021 Annual interest capitalization rates Inventories related to real estate business (%) 4.35-4.85 4.20-4.75 4.20-4.35 Property, plant and equipment (%) 0.96-4.03 0.49-3.47 0.48-1.08
Summary of Depreciation and Amortization	e. Depreciation and amortization For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Property, plant and equipment $ 45,240,667 $ 46,016,548 $ 48,604,160 $ 1,752,133 Right-of-use 1,055,458 946,880 1,114,950 40,193 Investment properties 594,110 562,260 751,047 27,074 Other intangible assets 3,576,606 3,733,377 4,054,120 146,147 Total $ 50,466,841 $ 51,259,065 $ 54,524,277 $ 1,965,547 Summary of depreciation by function Operating costs $ 43,749,333 $ 44,017,839 $ 46,880,267 $ 1,689,988 Operating expenses 3,140,902 3,507,849 3,589,890 129,412 $ 46,890,235 $ 47,525,688 $ 50,470,157 $ 1,819,400 Summary of amortization by function Operating costs $ 2,092,074 $ 2,231,060 $ 2,443,870 $ 88,099 Operating expenses 1,484,532 1,502,317 1,610,250 58,048 $ 3,576,606 $ 3,733,377 $ 4,054,120 $ 146,147
Summary of Operating Expenses Directly Related to Investment Properties	Operating expenses directly related to investment properties For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Direct operating expenses of investment properties that generated rental income $ 1,232,826 $ 1,121,854 $ 1,422,463 $ 51,278
Summary of Employee Benefits Expense	f. Employee benefits expense For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Post-employment benefits Defined contribution plans $ 3,148,209 $ 2,979,167 $ 3,489,642 $ 125,798 Defined benefit plans 277,041 217,186 214,599 7,736 3,425,250 3,196,353 3,704,241 133,534 Equity-settled share-based payments 871,699 955,575 699,211 25,206 Other employee benefits 70,279,752 76,648,412 90,412,118 3,259,269 $ 74,576,701 $ 80,800,340 $ 94,815,570 $ 3,418,009 Summary of employee benefits expense by function Operating costs $ 49,173,778 $ 52,526,164 $ 61,555,563 $ 2,219,018 Operating expenses 25,402,923 28,274,176 33,260,007 1,198,991 $ 74,576,701 $ 80,800,340 $ 94,815,570 $ 3,418,009
Summary of Employees' Compensation and Remuneration to Directors	g. Employees’ compensation and the remuneration to directors The Articles stipulates to distribute employees’ compensation and remuneration to directors at the rates of 0.01%-1.00% For the Year Ended December 31 2020 2021 Accrual Accrual Accrual Accrual Amount NT$ NT$ US$ (Note 4) Employees’ compensation 0.20 $ 54,909 0.19 $ 121,935 $ 4,396 Remuneration to directors 0.40 109,818 0.30 195,095 7,033
Summary of Appropriations of Employees' Compensation (Settled by Cash) and Remuneration to Directors	In March 2020 and 2021, the board of directors resolved the appropriations of employees’ compensation and remuneration to directors in cash for 2019 and 2020, respectively. The differences between the resolved amounts and the accrued amounts reflected in the annual consolidated financial statements for the years ended December 31, 2019 and 2020 were deemed changes in estimates. The differences were NT$3 thousand and NT$818 thousand (US$29 thousand) and were adjusted in net profit for each of the year ended December 31, 2020 and 2021, respectively. For Year 2019 For Year 2020 Employees’ Remuneration Employees’ Remuneration NT$ NT$ NT$ NT$ Resolved by the board of directors $ 34,400 $ 68,800 $ 54,909 $ 109,000 Recognized in the consolidated financial statements $ 34,400 $ 68,803 $ 54,909 $ 109,818

Income Tax (Tables)

Income Tax (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Major Components of Income Tax Expense	The major components of income tax were as follows: For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Current income tax In respect of the current year $ 5,002,954 $ 6,807,882 $ 14,533,570 $ 523,921 Income tax on unappropriated earnings 19,115 680,649 3,684,138 132,810 Changes in estimate for prior years (352,579 ) (472,512 ) (129,152 ) (4,656 ) 4,669,490 7,016,019 18,088,556 652,075 Deferred income tax In respect of the current year 563,512 212,338 (95,906 ) (3,457 ) Changes in tax rates 54,072 — 18,337 660 Changes in estimate for prior years (213,758 ) (103,021 ) 16,625 600 Effect of foreign currency exchange differences (62,070 ) (8,438 ) (83,840 ) (3,022 ) 341,756 100,879 (144,784 ) (5,219 ) Income tax expense recognized in profit or loss $ 5,011,246 $ 7,116,898 $ 17,943,772 $ 646,856
Summary of Reconciliation of Income Tax Expense	A reconciliation of income tax expense calculated at the statutory rates and income tax expense recognized in profit or loss was as follows: For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Profit before income tax $ 23,279,811 $ 35,768,798 $ 80,193,769 $ 2,890,906 Income tax expense calculated at the statutory rates $ 11,802,811 $ 16,907,904 $ 33,697,736 $ 1,214,771 Nontaxable expense in determining taxable income 459,133 316,619 357,936 12,903 Tax-exempt (495,883 ) (387,212 ) (14,578,355 ) (525,536 ) Additional income tax on unappropriated earnings 19,115 680,649 3,684,138 132,810 Income tax credits (898,198 ) (1,191,387 ) (1,654,821 ) (59,655 ) The origination and reversal of temporary differences (3,594,774 ) (6,033,652 ) 78,544 2,831 Income tax adjustments on prior years (352,579 ) (472,512 ) (112,527 ) (4,056 ) Unrecognized deferred tax liability for temporary differences associated with investments (1,993,561 ) (2,616,917 ) (6,135,120 ) (221,165 ) Unrecognized loss carryforwards — — 288,025 10,383 Realized investment loss on merger of subsidiary — (138,890 ) — — Withholding tax 65,182 52,296 87,175 3,143 Land value increment tax — — 117,341 4,230 Capital gains tax — — 2,113,700 76,197 Income tax expense recognized in profit or loss $ 5,011,246 $ 7,116,898 $ 17,943,772 $ 646,856
Summary of Income Tax Recognized Directly in Equity	b. Income tax recognized directly in equity For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Deferred income tax Related to employee share options $ 1,404 $ (1,159 ) $ (9 ) $ (0 )
Summary of Income Tax Recognized in Other Comprehensive Income	c. Income tax recognized in other comprehensive income For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Deferred income tax Related to remeasurement of defined benefit plans $ 74,308 $ 114,559 $ (19,319 ) $ (696 ) Unrealized loss on equity instruments at fair value through other comprehensive income (78,124 ) (237,460 ) (160,084 ) (5,771 ) Income tax recognized in other comprehensive income $ (3,816 ) $ (122,901 ) $ (179,403 ) $ (6,467 )
Summary of Current Tax Assets and Liabilities	d. Current tax assets and liabilities December 31 2020 2021 NT$ NT$ US$ (Note 4) Current tax assets Tax refund receivable $ 303,265 $ 207,272 $ 7,472 Prepaid income tax 399,555 334,908 12,073 $ 702,820 $ 542,180 $ 19,545 Current tax liabilities Income tax payable $ 6,514,502 $ 16,362,350 $ 589,847
Summary of Movements of Deferred Tax Assets and Deferred Tax Liabilities	e. Deferred tax assets and liabilities The Group offset certain deferred tax assets and deferred tax liabilities which met the offset criteria. The movements of deferred tax assets and deferred tax liabilities were as follows: For the year ended December 31, 2019 Balance at Recognized in Recognized in Other Recognized in Equity Exchange Acquisitions Balance at NT$ NT$ NT$ NT$ NT$ NT$ NT$ Deferred tax assets Temporary differences Property, plant and equipment $ 689,790 $ (119,972 ) $ — $ — $ (25,023 ) $ 49 $ 544,844 Defined benefit obligation 1,064,824 (57,746 ) 74,308 — (2,803 ) — 1,078,583 FVTPL financial instruments 211,556 47,991 — — (40 ) — 259,507 Others 1,838,746 (84,377 ) — 1,160 (24,906 ) 14,326 1,744,949 3,804,916 (214,104 ) 74,308 1,160 (52,772 ) 14,375 3,627,883 Loss carry-forward 672,275 (166,128 ) — — (12,203 ) 48,837 542,781 Investment credits 631,166 (86,722 ) — — (7,404 ) — 537,040 $ 5,108,357 $ (466,954 ) $ 74,308 $ 1,160 $ (72,379 ) $ 63,212 $ 4,707,704 Deferred tax liabilities Temporary differences Property, plant and equipment $ 5,236,104 $ (39,379 ) $ — $ — $ (7,074 ) $ 16,966 $ 5,206,617 FVTPL financial instruments 4,535 4,706 — — (49 ) — 9,192 Others 566,074 (90,524 ) 78,124 (244 ) (3,144 ) 6,142 556,428 $ 5,806,713 $ (125,197 ) $ 78,124 $ (244 ) $ (10,267 ) $ 23,108 $ 5,772,237 For the year ended December 31, 2020 (retrospectively adjusted) Balance at Recognized in Recognized in Other Recognized in Equity Exchange Acquisitions Disposal of Balance at NT$ NT$ NT$ NT$ NT$ NT$ NT$ NT$ Deferred tax assets Temporary differences Property, plant and equipment $ 544,844 $ 4,632 $ — $ — $ 12,435 $ 81,773 $ (13,982 ) $ 629,702 Defined benefit obligation 1,078,583 (36,633 ) 114,559 — 1,005 212,941 — 1,370,455 FVTPL financial instruments 259,507 (138,045 ) — — (7 ) 2,085 (11,281 ) 112,259 Others 1,744,949 679,197 — (999 ) (45,169 ) 150,291 (120,359 ) 2,407,910 3,627,883 509,151 114,559 (999 ) (31,736 ) 447,090 (145,622 ) 4,520,326 Loss carry-forward 542,781 (44,651 ) — — (915 ) 183,045 (152,594 ) 527,666 Investment credits 537,040 (86,100 ) — — (21,559 ) — — 429,381 $ 4,707,704 $ 378,400 $ 114,559 $ (999 ) $ (54,210 ) $ 630,135 $ (298,216 ) $ 5,477,373 Deferred tax liabilities Temporary differences Property, plant and equipment $ 5,206,617 $ 427,465 $ — $ — $ (29,248 ) $ 375,553 $ — $ 5,980,387 FVTPL financial instruments 9,192 (2,942 ) — — 67 — — 6,317 Others 556,428 54,755 237,460 160 (1,060 ) 287,375 (795 ) 1,134,323 $ 5,772,237 $ 479,278 $ 237,460 $ 160 $ (30,241 ) $ 662,928 $ (795 ) $ 7,121,027 For the year ended December 31, 2021 Balance at (retrospectively Recognized in Recognized in Other Recognized in Equity Exchange Disposal of Balance at NT$ NT$ NT$ NT$ NT$ NT$ NT$ Deferred tax assets Temporary differences Property, plant and equipment $ 629,702 $ (186,443 ) $ — $ — $ (7,178 ) $ (345,104 ) $ 90,977 Defined benefit obligation 1,370,455 (115,707 ) (19,319 ) — (47,276 ) — 1,188,153 FVTPL financial instruments 112,259 77,593 — — (502 ) — 189,350 Others 2,407,910 679,492 — (7 ) 52,399 (269,080 ) 2,870,714 4,520,326 454,935 (19,319 ) (7 ) (2,557 ) (614,184 ) 4,339,194 Loss carry-forward 527,666 187,981 — — (31,077 ) (45,788 ) 638,782 Investment credits 429,381 (15,549 ) — — (22,798 ) — 391,034 $ 5,477,373 $ 627,367 $ (19,319 ) $ (7 ) $ (56,432 ) $ (659,972 ) $ 5,369,010 Deferred tax liabilities Temporary differences Property, plant and equipment $ 5,980,387 $ 165,628 $ — $ — $ (42,437 ) $ (186,834 ) $ 5,916,744 FVTPL financial instruments 6,317 6,274 — — (11 ) — 12,580 Others 1,134,323 310,681 160,084 2 69,848 (14,065 ) 1,660,873 $ 7,121,027 $ 482,583 $ 160,084 $ 2 $ 27,400 $ (200,899 ) $ 7,590,197 Balance at (retrospectively adjusted) Recognized in Recognized in Other Recognized in Equity Exchange Disposal of Balance at US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Deferred tax assets Temporary differences Property, plant and equipment $ 22,700 $ (6,721 ) $ — $ — $ (259 ) $ (12,441 ) $ 3,279 Defined benefit obligation 49,404 (4,171 ) (696 ) — (1,704 ) — 42,833 FVTPL financial instruments 4,047 2,797 — — (18 ) — 6,826 Others 86,803 24,495 — (0 ) 1,889 (9,700 ) 103,487 162,954 16,400 (696 ) (0 ) (92 ) (22,141 ) 156,425 Loss carry-forward 19,022 6,777 — — (1,121 ) (1,651 ) 23,027 Investment credits 15,479 (561 ) — — (822 ) — 14,096 $ 197,455 $ 22,616 $ (696 ) $ (0 ) $ (2,035 ) $ (23,792 ) $ 193,548 Deferred tax liabilities Temporary differences Property, plant and equipment $ 215,587 $ 5,971 $ — $ — $ (1,530 ) $ (6,735 ) $ 213,293 FVTPL financial instruments 228 226 — — (1 ) — 453 Others 40,891 11,200 5,771 0 2,518 (507 ) 59,873 $ 256,706 $ 17,397 $ 5,771 $ 0 $ 987 $ (7,242 ) $ 273,619
Summary of Unrecognized Deferred Tax Assets Related to Loss Carry-forward, Investment Credits and Deductible Temporary Differences	f. Items for which no deferred tax assets have been recognized for loss carry-forward, investment credits and deductible temporary differences December 31 2020 2021 NT$ NT$ US$ (Note 4) Loss carry-forward $ 1,497,056 $ 1,340,849 $ 48,336 Investment credits 49,611 44,244 1,595 Deductible temporary differences 377,242 241,249 8,697 $ 1,923,909 $ 1,626,342 $ 58,628
Summary of Unused Loss Carry-forward	g. Information about unused loss carry-forward, unused investment credits, tax-exemption As of December 31, 2021, the unused loss carry-forward comprised: Expiry Year NT$ US$ (Note 4) 2022 $ 243,136 $ 8,765 2023 192,254 6,930 2024 171,664 6,188 2025 185,524 6,688 2026 and thereafter 1,187,051 42,792 $ 1,979,629 $ 71,363
Summary of Unused Investment Credits	As of December 31, 2021, unused investment credits comprised: Tax Credit Source Remaining Creditable Amount Expiry Year NT$ US$ (Note 4) Purchase of machinery and equipment $ 370,360 $ 13,351 2026 Others 64,918 2,340 2026 and thereafter $ 435,278 $ 15,691
Summary of Projects were Exempted From Income Tax	As of December 31, 2021, profits attributable to the following expansion project is exempted from income tax for a 5-year Tax-exemption Period Construction and expansion of ASE Test Inc. in 2009 2018.01 2022.12

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Earnings and Weighted Average Number of Ordinary Shares Outstanding in Computation of Earnings Per Share	The earnings and weighted average number of ordinary shares outstanding in the computation of earnings per share were as follows: Net profit for the year For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Profit for the year attributable to owners of the Company $ 17,060,591 $ 26,970,580 $ 60,150,167 $ 2,168,353 Effect of potentially dilutive ordinary shares: Potential ordinary s of the subsid iary (385,865 ) (521,073 ) (1,056,778 ) (38,096 ) Earnings used in the computation of diluted earnings per share $ 16,674,726 $ 26,449,507 $ 59,093,389 $ 2,130,257 Weighted average number of ordinary shares outstanding For the Year Ended December 31 2019 2020 2021 Weighted average number of ordinary shares in the 4,251,964 4,265,732 4,305,348 Effect of potentially dilutive ordinary shares Employee share options 10,232 22,086 58,113 Employees’ compensation 570 815 1,264 Employee restricted stock awards — — 943 Weighted average number of ordinary shares in the 4,262,766 4,288,633 4,365,668

Share-based Payment Arrangeme_2

Share-based Payment Arrangements (Tables)	12 Months Ended
	Dec. 31, 2021
Statement [LineItems]
Summary of Information About Restricted Shares	Information about USISH’s outstanding restricted st oc Range of (RMB) Remaining Contractual December 31, 2020 2019 restricted st ocks $ 13.2 3.3 2020 restricted stocks — 1.7 December 31, 2021 2019 restricted st ocks 12.7 2.3 2020 restricted stocks — 0.7 2021 restricted st oc — 1.7
ASE Inc. option plans [member]
Statement [LineItems]
Summary of Information About Share Options	Information about the share option plans that the Company granted and assumed For the Year Ended December 31 2019 2020 2021 Weighted Weighted Weighted Average Average Average Number of Exercise Number of Exercise Number of Exercise Options Price Options Price Options Price (In Per Share (In Per Share (In Per Share Thousands) (NT$) Thousands) (NT$) Thousands) (NT$) Balance at January 1 183,814 $ 58.1 170,786 $ 57.0 144,767 $ 56.9 Options expired — — (1,006 ) 40.8 — — Options forfeited (4,214 ) 61.8 (3,949 ) 58.0 (5,907 ) 52.3 Options exercised (8,814 ) 48.4 (21,064 ) 49.2 (42,058 ) 61.4 Balance at December 31 170,786 57.0 144,767 56.9 96,802 53.3 Options exercisable, end of year 33,822 63.5 67,388 61.4 49,696 55.5
Summary of Outstanding Share Options	Information about the outstanding share options that the Company granted and assumed at each balance sheet date was as follows: Range of (NT$) Weighted Contractual December 31, 2020 ASE 4 th $ 45.2 0.3 ASE 5 th 73.0 4.7 The Company 1 st 52.9 7.9 December 31, 2021 ASE 5 th 73.0 3.7 The Company 1 st 51.0 6.9
USIE option plans [member]
Statement [LineItems]
Summary of Information About Share Options	USIE The terms of the plans issued by USIE were the same with those option plans previously granted by ASE. Information about share options was as follows: For the Year Ended December 31 2019 2020 Weighted Weighted Number of Average Exercise Number of Average Exercise Options Price Options Price (In Per Share (In Per Share Thousands) (US$) Thousands) (US$) Balance at January 1 16,711 $ 2.1 8,349 $ 2.3 Options forfeited — — (7 ) 2.9 Options exercised (8,362 ) 2.0 (8,342 ) 2.3 Balance at December 31 8,349 2.3 — — Options exercisable, end of year 8,349 2.3 — —
Trinomial tree model [member]
Statement [LineItems]
Summary of Inputs Related to Fair Value of Share Options	For the fair values at the grant date of USISH’s 2019, 2020 and 2021 plans, the share options plans were measured by using the trinomial tree model, while the restricted stocks lock-up Share option plan 2019 Share 2020 Share Share price at the grant date RMB15.84 per share RMB21.55 per share Exercise price RMB13.34 per share RMB21.65 per share Expected volatility (%) 45.07-51.80 48.14-53.57 Expected lives (years) 3-5 2.2-4.2 Expected dividend yield — — Risk free interest rate (%) 2.80-2.97 2.80-2.99 Restricted stock 2019 Restricted S 2019 Restricted Stocks in 2020 2020 Restricted Stocks 2021 Restricted Stocks Share price at the grant date RMB16.30 per share RMB16.60 per share RMB24.30 per share RMB14.65 per share Exercise price RMB13.34 per share RMB13.34 per share (Note) (Note) Expected volatility (%) 47.77 57.21 56.97 47.15 Lock-up 1 1 1.3 1.3 Expected dividend yield — — — — Risk free interest rate (%) 2.70 1.55 2.63 2.34
USISH option plans [member]
Statement [LineItems]
Summary of Information About Share Options	Information about share options was as follows: For the Year Ended December 31 2019 2020 2021 Number of Exercise Number of Exercise Number of Exercise Options Price Options Price Options Price (In Per Share (In Per Share (In Per Share Thousands) (RMB) Thousands) (RMB) Thousands) (RMB) Balance at January 1 21,537 $ 15.5 35,077 $ 14.5 31,266 $ 14.6 Options granted 17,167 13.3 1,140 21.7 — — Options forfeited (463 ) 15.4 (636 ) 14.0 (952 ) 14.5 Options exercised (3,164 ) 15.5 (4,315 ) 15.5 (828 ) 13.8 Balance at December 31 35,077 14.5 31,266 14.6 29,486 14.2 Options exercisable, end of year 13,694 15.5 13,416 15.5 19,249 14.8 Fair value of options granted (RMB) $ 6.27-8.35 $ 7.03-8.93 $ —
Summary of Outstanding Share Options	Information about USISH’s outstanding share options at each balance sheet date was as follows: Range of (RMB) Remaining Contractual December 31, 2020 2015 share options $ 15.5 4.9 2019 share options 13.3 3.9 2020 share options 21.7 3.9 December 31, 2021 2015 share options 15.5 3.9 2019 share options 12.7 2.9 2020 share options 21.2 2.9
Summary of Information About Restricted Shares	Information about restricted stocks For the Year Ended December 31 2019 2020 2021 Number of Exercise Number of Exercise Number of Exercise Options Price Options Price Options Price (In Per Share (In Per Share (In Per Share Thousands) (RMB) Thousands) (RMB) Thousands) (RMB) Balance at January 1 — $ — 6,156 $ 13.3 5,547 $ 12.2 Options granted 6,156 13.3 672 4.9 281 — Options exercised — — (1,281 ) 13.2 (1,780 ) 12.7 Options forfeited — — — — (483 ) 12.1 Balance at December 31 6,156 13.3 5,547 12.2 3,565 10.2 Options exercisable, end of year — — — — — — Fair value of options granted (RMB) $ 13.47 $ 18.55 $ 11.78

Business Combinations (Tables)

Business Combinations (Tables)	12 Months Ended
	Dec. 31, 2021
Statement [LineItems]
Summary of Subsidiary Acquired	Principal Activity Date of Proportion of Consideration Transferred NT$ US$ (Note 4) AMPI Engaged in the manufacturing of integrated circuit April 30, 2019 50.97 $ 250,000 ASEEE Engaged in the production of embedded substrate April 26, 2019 51.00 $ — USIPL Engaged in the design and manufacturing of electronic components and new electronic applications October 31, 2019 60.00 $ 313,057 FAFG Holding company and the group engaged in the design and manufacturing of electronic components December 1, 2020 100.00 $ 12,443,637 ITGEU Trading company October 21, 2021 100.00 $ 50,368 $ 1,816 SER Engaged in the design and manufacturing of electronic components November 2, 2021 100.00 $ 217,919 $ 7,856
Summary of Consideration Transferred in business combination	b. Consideration Transferred AMPI ASEEE USIPL FAFG ITGEU SER NT$ NT$ NT$ NT$ NT$ US$ (Note 4) NT$ US$ (Note 4) Cash $ 250,000 $ — $ 313,057 $ 11,094,802 $ 50,368 $ 1,816 $ 217,919 $ 7,856 Equity instrument issued — — — 1,734,570 — — — — Contingent consideration arrangement — — — (385,735 ) — — — — Fair value of identifiable net assets acquired $ 250,000 $ — $ 313,057 $ 12,443,637 $ 50,368 $ 1,816 $ 217,919 $ 7,856
Summary of Assets Acquired and Liabilities Assumed at the Date of Acquisition	AMPI ASEEE USIPL FAFG ITGEU SER NT$ NT$ NT$ NT$ NT$ US$ (Note 4) NT$ US$ (Note 4) Assets Cash and cash equivalents $ 349,496 $ 23,197 $ 108,718 $ 2,349,164 $ 68,719 $ 2,477 $ 18,850 $ 680 Trade and other receivables 371,144 5,732 58,713 4,434,296 41,832 1,508 40,671 1,466 Inventories 403,887 11,033 229 4,836,819 — — 375,912 13,551 Property, plant and equipment 683,207 1,361,572 525,048 2,882,720 94 3 37,672 1,357 Intangible assets 128,900 290,757 11,704 1,541,155 32 1 368 14 Others 237,766 317,888 99,112 1,919,118 2,828 102 186,377 6,719 Liabilities Trade and other payables (224,295 ) (133,278 ) (217,887 ) (4,575,720 ) (29,165 ) (1,051 ) (214,883 ) (7,746 ) Borrowings and bonds payables (951,519 ) (1,371,395 ) (190,737 ) (356,417 ) — — — — Others (148,723 ) (290,273 ) (63,708 ) (3,155,051 ) (858 ) (31 ) (227,048 ) (8,185 ) Fair value of identifiable net assets acquired $ 849,863 $ 215,233 $ 331,192 $ 9,876,084 $ 83,482 $ 3,009 $ 217,919 $ 7,856
Summary of Goodwill Recognized on Acquisition	e. Goodwill recognized on acquisitions or gain recognized in bargain purchase transaction AMPI ASEEE USIPL FAFG ITGEU SER NT$ NT$ NT$ NT$ NT$ US$ (Note 4) NT$ US$ (Note 4) Consideration transferred $ 250,000 $ — $ 313,057 $ 12,443,637 $ 50,368 $ 1,816 $ 217,919 $ 7,856 Add: Fair value of 315,925 117,609 — — — — — — Add: Non-controlling 416,716 105,464 142,494 289 — — — — Less: Fair value of identifiable net assets acquired (849,863 ) (215,233 ) (331,192 ) (9,876,084 ) (83,482 ) (3,009 ) (217,919 ) (7,856 ) Goodwill recognized on acquisition (gain recognized in bargain purchase transaction) $ 132,778 $ 7,840 $ 124,359 $ 2,567,842 $ (33,114 ) $ (1,193 ) $ — $ —
Summary of Net Cash Outflow on Acquisition of Subsidiaries	f. Net cash outflow (inflow) on acquisition of subsidiaries AMPI ASEEE USIPL FAFG ITGEU SER NT$ NT$ NT$ NT$ NT$ US$ (Note 4) NT$ US$ (Note 4) Consideration transferred $ 250,000 $ — $ 313,057 $ 11,094,802 $ 50,368 $ 1,816 $ 217,919 $ 7,856 Less: Cash and cash equivalent acquired (349,496 ) (23,197 ) (108,718 ) (2,349,164 ) (68,719 ) (2,477 ) (18,850 ) (680 ) Net cash outflow (inflow) on acquisition of subsidiaries $ (99,496 ) $ (23,197 ) $ 204,339 $ 8,745,638 $ (18,351 ) $ (661 ) $ 199,069 $ 7,176
Summary of Impact of Acquisitions by Comprehensive Income	The results of operations since the acquisition date were included in the consolidated statements of comprehensive income and were as follows: AMPI (for the period ASEEE (for the period USIPL (for the period FAFG (for the period ITGEU (for the period October 21, 2021 SER (for the November 2, 2021 through NT$ NT$ NT$ NT$ NT$ US$ (Note 4) NT$ US$ (Note 4) Operating revenue $ 704,243 $ (1,159 ) $ 39,080 $ 2,043,440 $ 75,221 $ 2,712 $ 225,017 $ 8,112 Net profit (loss) $ (217,163 ) $ (469,598 ) $ (11,995 ) $ 91,179 $ (4,593 ) $ (166 ) $ (508 ) $ (18 )
Summary of identification of the difference between the cost of the investment and the Group's share of FAFG's net fair value of identifiable assets and liabilities	h. As of December 31, 2021, the Group has completed the identification of the difference between the cost of the investment and the Group’s share of FAFG’s net fair value of identifiable assets and liabilities, and has retrospectively adjusted the comparative consolidated financial statements as of and December 31, 2020 After Before NT$ NT$ Consolidated balance sheet Inventories $ 48,590,434 $ 48,516,459 Financial assets at fair value through profit or loss – non-current $ 2,180,978 $ 1,793,188 Property, plant and equipment $ 234,365,397 $ 233,207,324 Right-of-use $ 8,741,807 $ 8,620,612 Goodwill $ 52,709,053 $ 54,777,439 Other intangible assets $ 27,711,771 $ 26,808,668 Deferred tax liabilities $ 7,121,027 $ 6,551,233 Non-controlling $ 15,622,009 $ 15,616,053

Disposal of Subsidiaries (Table

Disposal of Subsidiaries (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Analysis of Assets and Liabilities on Date Control was Lost	a. Analysis of assets and liabilities on the date control was lost 2020 2021 SF GAPT Holding and ASEKS NT$ NT$ US$ (Note 4) Current Assets Cash and cash equivalent $ 200,347 $ 2,625,715 $ 94,655 Trade and other 318,425 4,505,531 162,420 Inventories 239,865 2,284,880 82,368 Other current assets 111,913 1,215,992 43,835 Non-Current Property, plant and equipment 7,546,413 16,693,129 601,770 Right-of-use 812,861 181,855 6,556 Investment property — 787,250 28,379 Goodwill — 310,711 11,201 Deferred tax assets 298,217 659,972 23,792 Other non-current assets 43,482 308,500 11,122 Current Liabilities Short-term borrowings — (2,443,005 ) (88,068 ) Trade and other payables (1,739,330 ) (5,949,592 ) (214,477 ) Current portion of long-term borrowings (1,746,000 ) — — Other current liabilities (24,564 ) (647,027 ) (23,325 ) Non-Current Long-term borrowings (2,947,682 ) — — Deferred tax liabilities (796 ) (200,899 ) (7,242 ) Lease liabilities – non-current — (8,150 ) (294 ) Other non-current liabilities — (156,863 ) (5,655 ) Net assets disposed of $ 3,113,151 $ 20,167,999 $ 727,037
Summary of Gain on Disposal of Subsidiaries	b. Gain on disposal of subsidiaries 2020 2021 SF GAPT Holding and ASEKS NT$ NT$ US$ (Note 4) Total consideration (paid in cash) $ 4,078,844 $ 36,939,133 $ 1,331,620 Net assets disposed of (3,113,151 ) (20,167,999 ) (727,037 ) Reclassification of accumulated exchange difference from equity to profit or loss due to the loss of control (162,940 ) 569,284 20,522 Gain on dis posals $ 802,753 $ 17,340,418 $ 625,105
Summary of Net Cash Inflow on Disposal of Susbsidiaries	c. Net cash inflow on disposals of subsidiaries 2020 2021 SF GAPT Holding and ASEKS NT$ NT$ US$ (Note 4) Consideration received in cash and cash equivalents $ 4,078,844 $ 36,939,133 $ 1,331,620 Less: Cash and cash equivalent balances disposed of (200,347 ) (2,625,715 ) (94,655 ) Other receivables (Note) (the outstanding receivables of consideration, net of relevant expenditure) (161,458 ) (10,533,600 ) (379,726 ) $ 3,717,039 $ 23,779,818 $ 857,239

Cash Flows Information (Tables)

Cash Flows Information (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Non-cash Investing Activities	a. Non-cash In addition to other notes, the Group entered into the following investing activities which include both cash and non-cash For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Payments for property, plant and equipment Purchase of property, plant and equipment $ 63,073,887 $ 59,024,201 $ 74,417,541 $ 2,682,681 Increase in other non-current 68,560 78,291 1,184,927 42,715 Decrease (increase) in other payables (6,254,579 ) 3,029,162 (4,671,228 ) (168,394 ) Capitalized borrowing costs (77,715 ) (54,208 ) (25,581 ) (922 ) $ 56,810,153 $ 62,077,446 $ 70,905,659 $ 2,556,080 Proceeds from disposal of property, plant and equipment Consideration from disposal of property, plant and equipment $ 441,444 $ 5,184,925 $ 1,128,850 $ 40,693 Increase in other non-current assets — — (134,760 ) (4,858 ) Increase (decrease) in other receivables 7,495 (735,812 ) 610,912 22,024 $ 448,939 $ 4,449,113 $ 1,605,002 $ 57,859 Payments for other intangible assets Purchase of other intangible assets $ 1,350,908 $ 982,655 $ 1,069,866 $ 38,568 Decrease in other payables 60,160 — — — $ 1,411,068 $ 982,655 $ 1,069,866 $ 38,568
Change in Liabilities Arising From Financing Activities	b. Changes in liabilities arising from financing activities For the year ended December 31, 2019 Short-term Bonds Long-term Lease Total NT$ NT$ NT$ NT$ NT$ Balance at January 1, 2019 $ 47,163,103 $ 16,985,936 $ 137,898,329 $ 6,084,729 $ 208,132,097 Net financing cash flows (4,683,142 ) 19,279,033 1,144,731 (636,556 ) 15,104,066 Interest under operating activities — — — 1,766 1,766 Non-cash Lease liabilities — — — 536,216 536,216 Acquisition through business combinations (Note 29) 656,820 245,664 1,523,968 81,649 2,508,101 Amortization of issuance cost — 11,522 189,151 — 200,673 Lease modifications — — — (239,321 ) (239,321 ) Short-term borrowings transferred to long-term borrowings (1,499,000 ) — 1,499,000 — — Effects of foreign currency exchange (1,065,452 ) — (1,176,581 ) (19,559 ) (2,261,592 ) Balance at December 31, 2019 $ 40,572,329 $ 36,522,155 $ 141,078,598 $ 5,808,924 $ 223,982,006 For the year ended December 31, 2020 Short-term Bonds Long-term Lease Total NT$ NT$ NT$ NT$ NT$ Balance at January 1, 2020 $ 40,572,329 $ 36,522,155 $ 141,078,598 $ 5,808,924 $ 223,982,006 Net financing cash flows (1,502,323 ) 19,717,149 (26,500,139 ) (844,357 ) (9,129,670 ) Interest under operating activities — — — 111 111 Rent expense under operating activities — — — (7,729 ) (7,729 ) Non-cash Lease liabilities — — — 584,642 584,642 Amortization of issuance cost — 14,250 156,982 — 171,232 Lease modifications — — — (289,687 ) (289,687 ) Short-term borrowings transferred to long-term borrowings (3,850,000 ) — 3,850,000 — — Adjustments for government subsidy — — 41,650 — 41,650 Acquisition of subsidiaries (Note 29) 356,417 — — 633,606 990,023 Disposal of subsidiaries (Note 30) — — (4,693,682 ) (670 ) (4,694,352 ) Effects of foreign currency exchange (978,565 ) — (1,542,685 ) (9,010 ) (2,530,260 ) Balance at December 31, 2020 $ 34,597,858 $ 56,253,554 $ 112,390,724 $ 5,875,830 $ 209,117,966 For the year ended December 31, 2021 Short-term Bonds Long-term (including financial Lease Total NT$ NT$ NT$ NT$ NT$ Balance at January 1, 2021 $ 34,597,858 $ 56,253,554 $ 112,390,724 $ 5,875,830 $ 209,117,966 Net financing cash flows 10,043,398 (3,719,057 ) 16,018,825 (907,403 ) 21,435,763 Interest under operating activities — — — 800 800 Rent expense under operating activities — — — (184 ) (184 ) Convertible bonds classified separately as equity components and embedded derivative liability — (399,955 ) — — (399,955 ) Non-cash changes Lease liabilities — — — 2,037,665 2,037,665 Amortization of issuance cost — 126,283 224,979 — 351,262 Convertible bonds issued by subsidiaries and converted to ordinary shares — (102 ) — — (102 ) Lease modifications — — — (58,799 ) (58,799 ) Acquisition of subsidiaries (Note 29) — — — 180,745 180,745 Disposal of subsidiaries (Note 30) (2,443,005 ) — — (32,655 ) (2,475,660 ) Reclassification — — — 380,292 380,292 Effects of foreign currency exchange (1,161,822 ) 6,614 (2,162,038 ) (76,407 ) (3,393,653 ) Balance at December 31, 2021 $ 41,036,429 $ 52,267,337 $ 126,472,490 $ 7,399,884 $ 227,176,140 Short-term Bonds Long-term (including financial Lease Total US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Balance at January 1, 2021 $ 1,247,219 $ 2,027,886 $ 4,051,577 $ 211,818 $ 7,538,500 Net financing cash flows 362,055 (134,068 ) 577,463 (32,711 ) 772,739 Interest under operating activities — — — 29 29 Rent expense under operating activities — — — (7 ) (7 ) Convertible bonds classified separately as equity components and embedded derivative liability — (14,418 ) — — (14,418 ) Non-cash changes Lease liabilities — — — 73,456 73,456 Amortization of issuance cost — 4,553 8,110 — 12,663 Convertible bonds issued by subsidiaries and converted to ordinary shares — (4 ) — — (4 ) Lease modifications — — — (2,120 ) (2,120 ) Acquisition of subsidiaries (Note 29) — — — 6,516 6,516 Disposal of subsidiaries (Note 30) (88,068 ) — — (1,177 ) (89,245 ) Reclassification — — — 13,709 13,709 Effects of foreign currency exchange (41,883 ) 238 (77,939 ) (2,754 ) (122,338 ) Balance at December 31, 2021 $ 1,479,323 $ 1,884,187 $ 4,559,211 $ 266,759 $ 8,189,480

Financial Instruments (Tables)

Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2021
Statement [LineItems]
Summary of Fair Value of Financial Instruments	The carrying amounts and fair value of bonds payable as of December 31, 2020 and 2021 were as follows: Carrying Amount Fair Value NT$ US$ (Note 4) NT$ US$ (Note 4) December 31, 2020 $ 56,253,554 $ 56,448,769 December 31, 2021 52,267,337 $ 1,884,187 52,429,758 $ 1,890,042
Summary of Financial Assets Measured at Level 3 Fair Value	For the year ended December 31, 2020 Financial Assets at FVTPL Financial Assets at FVTOCI Financial Assets Equity Debt Equity Debt Total NT$ NT$ NT$ NT$ NT$ Balance at January 1 $ 1,005,714 $ — $ 755,903 $ 3,044,562 $ 4,806,179 Recognized in profit or loss (17,941 ) — — — (17,941 ) Recognized in other comprehensive income Included in unrealized losses on financial assets at FVTOCI — — (149,856 ) (2,136 ) (151,992 ) Effects of foreign currency exchange (15,455 ) — (15,562 ) — (31,017 ) Net increase in trade receivables — 370,110 — 5,635,706 6,005,816 Trade receivables factoring — (370,110 ) — (7,038,983 ) (7,409,093 ) Purchases 893,234 — 259,168 — 1,152,402 Disposals (329,370 ) — (121,255 ) — (450,625 ) Acquisition through business combinations 387,790 — — — 387,790 Exercise of call option (25,988 ) — — — (25,988 ) Balance at December 31 (retrospectively adjusted) $ 1,897,984 $ — $ 728,398 $ 1,639,149 $ 4,265,531 For the year ended December 31, 2021 Financial Assets at FVTPL Financial Assets at FVTOCI Financial Assets Equity Debt Equity Debt Total NT$ NT$ NT$ NT$ NT$ Balance at January 1 (retrospectively adjusted) $ 1,897,984 $ — $ 728,398 $ 1,639,149 $ 4,265,531 Recognized in profit or loss 131,276 — — — 131,276 Recognized in other comprehensive income Included in unrealized losses on financial assets at FVTOCI — — 129,726 63,722 193,448 Effects of foreign currency exchange (79,614 ) — (4,508 ) — (84,122 ) Net increase in trade receivables — 3,269,782 — 14,940,539 18,210,321 Trade receivables factoring — (3,269,782 ) — (9,474,490 ) (12,744,272 ) Purchases 459,046 — 32,246 — 491,292 Disposals (107,793 ) — (14,873 ) — (122,666 ) Reclassify — — (29,758 ) — (29,758 ) Balance at December 31 $ 2,300,899 $ — $ 841,231 $ 7,168,920 $ 10,311,050 Financial Assets at FVTPL Financial Assets at FVTOCI Financial Assets Equity Debt Equity Debt Total US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ Balance at January 1 (retrospect ively adjusted) $ 68,421 $ — $ 26,257 $ 59,089 $ 153,767 Recognized in profit or loss 4,732 — — — 4,732 Recognized in other comprehensive income Included in unrealized losses on financial assets at FVTOCI — — 4,677 2,297 6,974 Effects of foreign currency exchange (2,870 ) — (163 ) — (3,033 ) Net increase in trade receivables — 117,872 — 538,592 656,464 Trade receivables factoring — (117,872 ) — (341,546 ) (459,418 ) Purchases 16,548 — 1,163 — 17,711 Disposals (3,886 ) — (536 ) — (4,422 ) Reclassify — — (1,073 ) — (1,073 ) Balance at December 31 $ 82,945 $ — $ 30,325 $ 258,432 $ 371,702
Summary of Categories of Financial Instruments	c. Categories of financial instruments December 31 2020 (Retrospectively 2021 NT$ NT$ US$ (Note 4) Financial assets FVTPL Mandatorily at FVTPL $ 6,523,583 $ 5,436,280 $ 195,973 Measured at amortized cost (Note 1) 147,521,583 200,732,680 7,236,218 FVTOCI Equity instruments 728,398 943,354 34,007 Debt instruments 1,012,736 1,076,458 38,805 Trade receivables, net 626,413 6,092,462 219,627 Financial liabilities FVTPL Held for trading 1,537,208 417,660 15,056 Financial liabilities for hedging 11,188,244 11,497,896 414,488 Measured at amortized cost (Note 2) 304,737,749 339,445,544 12,236,683 Note 1: The balances included financial assets measured at amortized cost which comprised cash and cash equivalents, trade and other receivables and other financial assets. Note 2: The balances included financial liabilities measured at amortized cost which comprised short-term borrowings, trade and other payables, bonds payable and long-term borrowings.
Summary of Detailed Information About Hedged	December 31, 2020 Hedging Instrument/Hedged Items Line item in Carrying Amount Balance sheet Asset Liability NT$ NT$ Fair value hedge Borrowings denominated in foreign currencies/ Financial assets at FVTPL Financial liabilities for hedging - current $ — $ 3,307,018 Hedge of net investment in foreign operation Financial liabilities for hedging - current — 1,970,307 Hedge of net investment in foreign operation Financial liabilities for hedging - non-current — 5,910,919 December 31, 2021 Hedging Instrument/Hedged Items Line item in Carrying Amount Balance sheet Asset Liability NT$ US$ (Note 4) NT$ US$ (Note 4) Fair value hedge Borrowings denominated in foreign currencies/ Financial assets at FVTPL Financial liabilities for hedging - current $ — $ — $ 2,954,921 $ 106,522 Hedge of net investment in foreign operation Financial liabilities for hedging - current — — 3,762,044 135,618 Hedge of net investment in foreign operation Financial liabilities for hedging - non-current — — 4,780,931 172,348
Summary of Detailed Information About Hedged Items	Change in Value Used for Calculating Hedge Ineffectiveness Accumulated Gains or Losses in Other Equity Carrying Accumulated Hedging Instrument/Hedged Item Hedging Hedged Item Continuing Hedge Asset Asset NT$ NT$ NT$ NT$ NT$ NT$ Fair value hedge Borrowings denominated in foreign currencies/ Financial assets at FVTPL $ 157,842 $ (157,842 ) $ — $ — $ 2,859,132 $ (142,217 ) Hedge of net investment in foreign operation 574,824 (574,824 ) (574,824 ) — — — Change in Value Used for Calculating Hedge Ineffectiveness Accumulated Gains or Losses in Other Equity Carrying Accumulated Hedging Instrument/Hedged Item Hedging Hedged Continuing Hedge Asset Asset NT$ NT$ NT$ NT$ NT$ NT$ Fair value hedge Borrowings denominated in foreign currencies/ Financial assets at FVTPL $ 94,145 $ (94,145) $ — $ — $ 2,318,517 $ (236,362) Hedge of net investment in foreign operation (738,600 ) 738,600 163,776 — — — Change in Value Used for Calculating Hedge Ineffectiveness Accumulated Gains or Losses in Other Equity Carrying Accumulated Hedging Instrument/ Hedged Item Hedging Hedged Item Continuing Hedge Asset Asset US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Fair value hedge Borrowings denominated in foreign currencies/ Financial assets at FVTPL $ 3,394 $ (3,394 ) $ — $ — $ 83,580 $ (8,521 ) Hedge of net investment in foreign operation (26,626 ) 26,626 5,904 — — —
Summary of Maturity Analysis for Non-derivative Financial Liabilities	December 31, 2020 On Demand or 1 Month 1 to 3 3 Months 1 Year 1 to 5 Years More than 5 Years NT$ NT$ NT$ NT$ NT$ Non-derivative Non-interest $ 43,111,390 $ 44,122,659 $ 8,223,684 $ 319,510 $ 176,536 Obligation under leases 103,734 151,921 619,908 1,779,041 4,088,301 Floating interest rate liabilities 13,792,596 8,190,076 10,214,154 102,253,481 7,999,130 Fixed interest rate liabilities 11,895,281 528,290 3,349,614 46,900,450 5,631,522 $ 68,903,001 $ 52,992,946 $ 22,407,360 $ 151,252,482 $ 17,895,489 December 31, 2021 On Demand or 1 Month 1 to 3 Months 3 Months to 1 Year 1 to 5 Years More than 5 Years NT$ NT$ NT$ NT$ NT$ Non-derivative financial liabilities Non-interest $ 52,353,176 $ 48,140,652 $ 10,216,253 $ 291,480 $ 114,201 Obligation under leases 84,978 157,710 687,144 2,585,624 4,929,602 Floating interest rate liabilities 12,565,548 5,180,527 13,416,893 112,493,242 7,494,670 Fixed interest rate liabilities 10,262,781 3,093,668 12,978,593 43,555,458 5,479,867 $ 75,266,483 $ 56,572,557 $ 37,298,883 $ 158,925,804 $ 18,018,340 On Demand or 1 Month 1 to 3 Months 3 Months to 1 Year 1 to 5 Years More than 5 Years US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Non-derivative financial liabilities Non-interest $ 1,887,281 $ 1,735,424 $ 368,286 $ 10,508 $ 4,117 Obligation under leases 3,063 5,685 24,771 93,209 177,707 Floating interest rate liabilities 452,976 186,753 483,666 4,055,272 270,176 Fixed interest rate liabilities 369,963 111,524 467,866 1,570,132 197,544 $ 2,713,283 $ 2,039,386 $ 1,344,589 $ 5,729,121 $ 649,544
Summary of Maturity Analysis for Derivative Financial Instruments	On Demand 1 Month 1 to 3 3 Months to 1 Year More than NT$ NT$ NT$ December 31, 2020 Net settled Forward exchange contracts $ 30,514 $ 18,429 $ — $ — Gross settled Forward exchange contracts Inflows $ 8,862,682 $ 5,565,137 $ 531,336 $ — Outflows (8,798,238 ) (5,518,153 ) (526,880 ) — 64,444 46,984 4,456 — Swap contracts Inflows 19,311,999 17,179,871 36,739,200 — Outflows (19,524,820 ) (17,486,997 ) (37,495,172 ) — (212,821 ) (307,126 ) (755,972 ) — Target redemption forward contracts Inflows 42,720 96,120 416,520 227,128 Outflows (44,471 ) (100,060 ) (433,595 ) (236,081 ) (1,751 ) (3,940 ) (17,075 ) (8,953 ) $ (150,128 ) $ (264,082 ) $ (768,591 ) $ (8,953 ) On Demand or 1 Month 1 to 3 Months 3 Months to 1 Year NT$ NT$ NT$ December 31, 2021 Net settled Forward exchange contracts $ (21,379 ) $ (1,410 ) $ — Gross settled Forward exchange contracts Inflows $ 2,382,315 $ 6,817,411 $ 531,596 Outflows (2,380,359 ) (6,784,689 ) (525,920 ) 1,956 32,722 5,676 Swap contracts Inflows 23,759,435 21,272,450 37,841,805 Outflows (23,814,701 ) (21,314,442 ) (37,965,438 ) (55,266 ) (41,992 ) (123,633 ) Target redemption forward contracts Inflows 19,376 43,596 33,216 Outflows (18,845 ) (42,401 ) (32,243 ) 531 1,195 973 $ (52,779 ) $ (8,075 ) $ (116,984 ) On Demand or 1 Month 1 to 3 Months 3 Months to US$ (Note 4) US$ (Note 4) US$ (Note 4) December 31, 2021 Net settled Forward exchange contracts $ (771 ) $ (51 ) $ — Gross settled Forward exchange contracts Inflows $ 85,880 $ 245,761 $ 19,164 Outflows (85,810 ) (244,581 ) (18,959 ) 70 1,180 205 Swap contracts Inflows 856,505 766,851 1,364,160 Outflows (858,497 ) (768,365 ) (1,368,617 ) (1,992 ) (1,514 ) (4,457 ) Target redemption forward contracts Inflows 698 1,572 1,197 Outflows (679 ) (1,529 ) (1,162 ) 19 43 35 $ (1,903 ) $ (291 ) $ (4,217 )
Summary of Disclosure of Detailed Information about Maturity Analysis of Obligation under Leases	Further information for maturity analysis of obligation under leases was as follows: Less than 1 Year 1 to 5 5 to 10 10 to 15 Years 15 to 20 Years More than 20 Years NT$ NT$ NT$ NT$ NT$ NT$ Obligation under leases $ 875,563 $ 1,779,041 $ 1,422,331 $ 776,735 $ 674,446 $ 1,214,789 Further information for maturity analysis of obligation under leases was as follows: Less than 1 Year 1 to 5 Years 5 to 10 Years 10 to 15 Years 15 to 20 Years More than 20 Years NT$ NT$ NT$ NT$ NT$ NT$ Obligation under leases $ 929,832 $ 2,585,624 $ 1,731,995 $ 883,335 $ 802,765 $ 1,511,507 Less than 1 Year 1 to 5 Years 5 to 10 Years 10 to 15 Years 15 to 20 Years More than 20 Years US$ US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) Obligation under leases $ 33,519 $ 93,209 $ 62,437 $ 31,843 $ 28,939 $ 54,488
Interest rate risk [member]
Statement [LineItems]
Summary of Interest Rate Risk	The carrying amounts of the Group’s financial assets and financial liabilities with exposure to interest rates at each balance sheet date were as follows: December 31 2020 2021 NT$ NT$ US$ (Note 4) Fair value interest rate risk Financial assets $ 5,049,005 $ 5,474,105 $ 197,336 Financial liabilities 56,599,417 76,206,394 2,747,166 Cash flow interest rate risk Financial assets 45,489,788 69,654,969 2,510,994 Financial liabilities 131,715,366 158,557,225 5,715,834
Measured at fair value on a recurring basis [member]
Statement [LineItems]
Summary of Fair Value of Financial Instruments	1) Fair value hierarchy Level 1 Level 2 Level 3 Total NT$ NT$ NT$ NT$ December 31, 2020 (retrospectively adjusted) Financial assets at FVTPL Derivative financial assets Forward exchange contracts $ — $ 122,511 $ — $ 122,511 Swap contracts — 99,312 — 99,312 Non-derivative Quoted ordinary shares 4,064,438 — — 4,064,438 Private-placement funds — — 1,124,754 1,124,754 Contingent considerations — — 387,790 387,790 Unquoted preferred shares — — 385,440 385,440 Open-end 339,338 — — 339,338 $ 4,403,776 $ 221,823 $ 1,897,984 $ 6,523,583 Financial assets at FVTOCI Investments in equity instruments Unquoted ordinary shares $ — $ — $ 567,377 $ 567,377 Unquoted preferred shares — — 151,329 151,329 Limited partnership — — 9,692 9,692 Investments in debt instruments Unsecured subordinate corporate bonds — — 1,012,736 1,012,736 Trade receivables, net — — 626,413 626,413 $ — $ — $ 2,367,547 $ 2,367,547 Financial liabilities at FVTPL Derivative financial liabilities Swap contracts $ — $ 1,448,972 $ — $ 1,448,972 Target redemption forward contracts — 79,216 — 79,216 Forward exchange contracts — 9,020 — 9,020 $ — $ 1,537,208 $ — $ 1,537,208 Level 1 Level 2 Level 3 Total NT$ US$ (Note 4) NT$ US$ (Note 4) NT$ US$ (Note 4) NT$ US$ (Note 4) December 31, 2021 Financial assets at FVTPL Derivative financial assets Swap contracts $ — $ — $ 85,629 $ 3,087 $ — $ — $ 85,629 $ 3,087 Forward exchange contracts — — 23,373 843 — — 23,373 843 Redemption option and put option of convertible bonds — — 8,463 305 — — 8,463 305 Target redemption forward contracts — — 500 18 — — 500 18 Non-derivative Quoted ordinary shares 2,683,193 96,726 — — — — 2,683,193 96,726 Private-placement funds — — — — 1,322,686 47,682 1,322,686 47,682 Unquoted preferred shares — — — — 583,270 21,026 583,270 21,026 Conti n — — — — 394,943 14,237 394,943 14,237 Open-end 334,223 12,049 — — — — 334,223 12,049 $ 3,017,416 $ 108,775 $ 117,965 $ 4,253 $ 2,300,899 $ 82,945 $ 5,436,280 $ 195,973 Financial assets at FVTOCI Investments in equity instruments Unquoted ordinary shares $ — $ — $ — $ — $ 820,779 $ 29,588 $ 820,779 $ 29,588 Quoted ordinary shares 102,124 3,682 — — — — 102,124 3,682 Unquoted preferred shares — — — — 11,245 405 11,245 405 Limited partnership — — — — 9,206 332 9,206 332 Investments in debt instruments Unsecured subordinate corporate bonds — — — — 1,076,458 38,805 1,076,458 38,805 Trade receivables, net — — — — 6,092,462 219,627 6,092,462 219,627 $ 102,124 $ 3,682 $ — $ — $ 8,010,150 $ 288,757 $ 8,112,274 $ 292,439 Financial liabilities at FVTPL Derivative financial liabilities Swap contracts $ — $ — $ 360,797 $ 13,006 $ — $ — $ 360,797 $ 13,006 Forward exchange contracts — — 56,863 2,050 — — 56,863 2,050 $ — $ — $ 417,660 $ 15,056 $ — $ — $ 417,660 $ 15,056

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Transactions Between Related Parties	b. Contribution of related party For the Year Ended December 31 Relationship and Name of Related Party 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Substantial related party ASE Cultural and Educational Foundation $ 100,000 $ — $ 10,000 $ 360 ASE Environmental Protection and Sustainability Foundation — 100,000 100,000 3,605 $ 100,000 $ 100,000 $ 110,000 $ 3,965
Summary of Compensation to Key Management Personnel	For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Short-term employee benefits $ 1,027,191 $ 1,264,980 $ 1,744,903 $ 62,902 Post-employment benefits 2,208 2,007 3,505 126 Share-based payments 134,544 153,774 163,697 5,901 $ 1,163,943 $ 1,420,761 $ 1,912,105 $ 68,929

Assets Pledged as Collateral _2

Assets Pledged as Collateral or for Security (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Assets Pledged as Collateral or for Security	The following assets were provided as collateral for bank borrowings, tariff guarantees of imported raw materials or collateral: December 31 2020 2021 NT$ NT$ US$ (Note 4) Inventories related to real estate business $ 10,564,873 $ 2,587,110 $ 93,263 Property, plant and equipment 124,124 114,390 4,124 Investment properties 11,847,145 20,796,862 749,707 Other financial assets (including current and non-current) 460,890 444,358 16,018 $ 22,997,032 $ 23,942,720 $ 863,112

Significant Assets and Liabil_2

Significant Assets and Liabilities Denominated in Foreign Currencies (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Significant Assets and Liabilities Denominated in Foreign Currencies	The following information was aggregated by the foreign currencies other than functional currencies of the group entities and the exchange rates between foreign currencies and respective functional currencies were disclosed. The significant financial assets and liabilities denominated in foreign currencies were as follows: Foreign (In Thousand) Exchange Rate Carrying Amount (In Thousand) December 31, 2020 Monetary financial assets US$ $ 4,269,075 US$1=NT$28.48 $ 121,583,265 US$ 1,527,381 US$1=RMB6.5249 43,499,803 US$ 41,643 US$1=EUR0.8143 1,185,984 JPY 13,544,360 JPY1=NT$0.2763 3,742,306 JPY 1,174,208 JPY1=US$0.0097 324,434 HKD 174,765 HKD1=NT$3.6730 641,912 Monetary financial liabilities US$ 4,439,915 US$1=NT$28.48 126,448,786 US$ 1,517,568 US$1=RMB6.5249 43,220,325 US$ 20,896 US$1=EUR0.8143 595,128 JPY 13,657,967 JPY1=NT$0.2763 3,773,695 JPY 1,188,650 JPY1=US$0.0097 328,424 HKD 18,814 HKD1=NT$3.6730 69,103 December 31, 2021 Monetary financial assets US$ 4,885,163 US$1=NT$27.68 135,221,324 US$ 1,718,314 US$1=RMB6.3757 47,562,940 US$ 42,250 US$1=EUR0.8829 1,169,492 JPY 12,584,942 JPY1=NT$0.2405 3,026,677 JPY 551,496 JPY1=US$0.0087 132,635 Monetary financial liabilities US$ 4,899,633 US$1=NT$27.68 135,621,853 US$ 1,503,606 US$1=RMB6.3757 41,619,803 US$ 88,741 US$1=EUR0.8829 2,456,363 JPY 14,078,075 JPY1=NT$0.2405 3,385,776 JPY 990,667 JPY1=US$0.0087 238,255
Summary of Realized and Unrealized Foreign Exchange Gain (Loss)	The significant realized and unrealized foreign exchange gain (loss) were as follows: For the Year Ended December 31 2019 2020 2021 Functional Currencies Exchange Rate Net Foreign Exchange Rate Net Foreign Exchange Rate Net Foreign Exchange Gain (Loss) NT$ NT$ NT$ US$ (Note 4) US$ US$1=NT$29.98 $ (84,177 ) US$1=NT$28.48 $ (143,804 ) US$1=NT$27.68 $ 132,582 $ 4,780 NT$ 1,203,823 1,382,067 1,413,969 50,972 RMB RMB1=NT$4.2975 14,055 RMB1=NT$4.3648 (181,624 ) RMB1=NT$4.3415 (85,675 ) (3,089 ) $ 1,133,701 $ 1,056,639 $ 1,460,876 $ 52,663

Operating Segments Information

Operating Segments Information (Tables)	12 Months Ended
	Dec. 31, 2021
Text block [abstract]
Summary of Segment Information	a. Segment revenues and operation results Adjustments Packaging Testing EMS Others and Eliminations Total NT$ NT$ NT$ NT$ NT$ NT$ For the year ended December 31, 2019 Revenue from external customers $ 198,916,897 $ 42,658,686 $ 165,789,479 $ 5,817,122 $ — $ 413,182,184 Inter-group revenues (Note 1) 5,370,963 231,399 60,638,567 7,431,399 (73,672,328 ) — Segment revenues 204,287,860 42,890,085 226,428,046 13,248,521 — 486,854,512 Interest income 186,291 90,091 249,487 284,458 (260,646 ) 549,681 Interest expense (3,403,475 ) (545,609 ) (255,404 ) (243,013 ) 260,646 (4,186,855 ) Depreciation and amortization (33,456,831 ) (12,379,703 ) (2,534,825 ) (2,095,482 ) — (50,466,841 ) Share of the profit or loss of associates and joint ventures 75,303 39,852 67,120 — — 182,275 Impairment loss (601,066 ) (141 ) — — — (601,207 ) Segment profit before income tax 7,572,763 10,321,537 6,082,106 (696,595 ) — 23,279,811 Expenditures for segment assets 35,462,305 23,966,051 2,770,129 875,402 — 63,073,887 December 31, 2019 Investments accounted for using the equity method 8,867,316 1,123,490 2,094,401 — — 12,085,207 Contract assets 4,162,124 1,735,192 — — — 5,897,316 For the year ended December 31, 2020 Revenue from external customers 218,666,071 47,271,074 204,690,669 6,350,896 — 476,978,710 Inter-group revenues (Note 1) 10,436,168 435,587 21,472,775 7,234,303 (39,578,833 ) — Segment revenues 229,102,239 47,706,661 226,163,444 13,585,199 — 516,557,543 Interest income 133,160 79,821 275,766 32,036 — 520,783 Interest expense (2,244,280 ) (564,269 ) (443,519 ) (185,160 ) — (3,437,228 ) Depreciation and amortization (32,333,229 ) (14,189,024 ) (2,877,546 ) (1,859,266 ) — (51,259,065 ) Share of the profit or loss of associates and joint ventures 362,133 99,670 85,809 — — 547,612 Impairment loss (218,600 ) (773,673 ) — — — (992,273 ) Segment profit before income tax 17,476,440 10,277,760 8,438,766 (424,168 ) — 35,768,798 Expenditures for segment assets 38,643,303 14,275,397 5,614,409 491,092 — 59,024,201 December 31, 2020 Investments accounted for using the equity method 9,146,344 1,340,307 2,320,022 — — 12,806,673 Contract assets 3,641,244 1,141,660 — — — 4,782,904 For the year ended December 31, 2021 Revenue from external customers 272,543,899 49,978,736 239,488,267 7,986,231 — 569,997,133 Inter-group revenues (Note 1) 7,244,889 339,619 27,825,073 7,527,260 (42,936,841 ) — Segment revenues 279,788,788 50,318,355 267,313,340 15,513,491 — 612,933,974 Interest income 61,141 88,874 301,072 91,242 — 542,329 Interest expense (1,604,107 ) (405,648 ) (629,584 ) (159,596 ) — (2,798,935 ) Depreciation and amortization (34,384,500 ) (13,819,080 ) (4,336,266 ) (1,984,431 ) — (54,524,277 ) Share of the profit or loss of associates and joint ventures 737,650 66,107 95,943 — — 899,700 Impairment loss (86,997 ) (39,769 ) — — — (126,766 ) Segment profit before income tax 41,581,126 11,998,938 8,528,675 18,085,030 — 80,193,769 Expenditures for segment assets 48,531,368 16,773,513 7,654,560 1,458,100 — 74,417,541 December 31, 2021 Investments accounted for using the equity method 12,744,756 1,896,372 2,355,472 — — 16,996,600 Contract assets 4,735,181 872,028 — — — 5,607,209 Adjustments Packaging Testing EMS Others and Eliminations Total US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) US$ (Note 4) For the year ended December 31, 2021 Revenue from external customers $ 9,824,942 $ 1,801,685 $ 8,633,319 $ 287,896 $ — $ 20,547,842 Inter-group revenues (Note 1) 261,171 12,243 1,003,067 271,350 (1,547,831 ) — Segment revenues 10,086,113 1,813,928 9,636,386 559,246 — 22,095,673 Interest income 2,204 3,204 10,853 3,289 — 19,550 Interest expense (57,827 ) (14,623 ) (22,696 ) (5,753 ) — (100,899 ) Depreciation and amortization (1,239,528 ) (498,164 ) (156,318 ) (71,537 ) — (1,965,547 ) Share of the profit or loss of associates and joint ventures 26,591 2,383 3,459 — — 32,433 Impairment loss (3,137 ) (1,434 ) — — — (4,571 ) Segment profit before income tax 1,498,959 432,550 307,450 651,947 — 2,890,906 Expenditures for segment assets 1,749,509 604,669 275,940 52,563 — 2,682,681 December 31, 2021 Investments accounted for using the equity method 459,436 68,362 84,913 — — 612,711 Contract assets 170,698 31,436 — — — 202,134 Note 1: Inter-group revenues were eliminated upon consolidation. Note 2: The disaggregated product and service type from the Group’s contract with customer is the same as those disclosed in above reportable segment.
Summary of Revenue from Major Products and Services	b. Revenue from major products and services For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) Packaging service $ 198,916,897 $ 218,666,071 $ 272,543,899 $ 9,824,942 Testing service 42,658,686 47,271,074 49,978,736 1,801,685 EMS 165,789,479 204,690,669 239,488,267 8,633,319 Others 5,817,122 6,350,896 7,986,231 287,896 $ 413,182,184 $ 476,978,710 $ 569,997,133 $ 20,547,842
Summary of Geographical Information	c. Geographical information The Group’s revenue from external customers by location of headquarter and information about its non-current 1) Net revenues from external customers For the Year Ended December 31 2019 2020 2021 NT$ NT$ NT$ US$ (Note 4) United States $ 245,521,027 $ 297,117,001 $ 353,500,361 $ 12,743,344 Taiwan 51,244,470 64,829,301 94,598,067 3,410,168 Asia 75,938,364 74,447,091 62,523,167 2,253,900 Europe 38,613,132 39,477,306 57,910,641 2,087,622 Others 1,865,191 1,108,011 1,464,897 52,808 $ 413,182,184 $ 476,978,710 $ 569,997,133 $ 20,547,842 2) Non-current assets December 31 2020 (Retrospectively Adjusted) 2021 NT$ NT$ US$ (Note 4) Taiwan $ 239,353,978 $ 252,525,376 $ 9,103,294 China 66,253,694 65,375,423 2,356,720 Others 31,875,938 34,702,992 1,251,009 $ 337,483,610 $ 352,603,791 $ 12,711,023

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Detail)	Dec. 31, 2021TWD-USDshares	Dec. 31, 2020shares
Disclosure of subsidiaries [line items]
Convenience exchange rate | TWD-USD	27.74
Number of shares in entity held by entity	72,941,000	72,941,000
Bottom of range [member]
Disclosure of subsidiaries [line items]
Number of shares in entity held by entity	1
Percentage of total shares held in Subsidiaries	0.10%

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Summary of Subsidiaries (Detail)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
The Company [Member] | ASE [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors
Establishment and Operating Location	R.O.C.
Percentage of Ownership (%)	100.00%	100.00%
The Company [Member] | USIINC [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	R.O.C.
Percentage of Ownership (%)	100.00%	100.00%
The Company [Member] | SPIL [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the assembly, testing and turnkey services of integrated circuit
Establishment and Operating Location	R.O.C.
Percentage of Ownership (%)	100.00%	100.00%
ASE [Member] | ASE Holding Limited [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	Bermuda
Percentage of Ownership (%)	100.00%	100.00%
ASE [Member] | J & R Holding Limited ("J&R Holding") [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	Bermuda
Percentage of Ownership (%)	100.00%	100.00%
ASE [Member] | Innosource Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	British Virgin Islands
Percentage of Ownership (%)	100.00%	100.00%
ASE [Member] | Omniquest Industrial Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	British Virgin Islands
Percentage of Ownership (%)	71.00%	71.00%
ASE [Member] | ASE Marketing & Service Japan Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in marketing and sales services
Establishment and Operating Location	Japan
Percentage of Ownership (%)	100.00%	100.00%
ASE [Member] | ASE Test, Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the testing of semiconductors
Establishment and Operating Location	R.O.C.
Percentage of Ownership (%)	100.00%	100.00%
ASE [Member] | Luchu Development Corporation [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the development of real estate properties
Establishment and Operating Location	R.O.C.
Percentage of Ownership (%)	67.10%	67.10%
ASE [Member] | Advanced Microelectronic Products Inc. ("AMPI") [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the manufacturing of integrated circuit
Establishment and Operating Location	R.O.C.
Percentage of Ownership (%)	7.60%	7.60%
ASE Test Inc [Member] | Luchu Development Corporation [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the development of real estate properties
Establishment and Operating Location	R.O.C.
Percentage of Ownership (%)	19.00%	19.00%
ASE Test Inc [Member] | TLJ Intertech Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in information software services
Establishment and Operating Location	R.O.C.
Percentage of Ownership (%)	60.00%	60.00%
ASE Test Inc [Member] | MingFeng Information Service Corp., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	In the process of liquidation (Liquidation completed in February 2022)
Establishment and Operating Location	R.O.C.
Percentage of Ownership (%)	100.00%	100.00%
ASE Test Inc [Member] | Advanced Microelectronic Products Inc. ("AMPI") [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the manufacturing of integrated circuit
Establishment and Operating Location	R.O.C.
Percentage of Ownership (%)	43.40%	43.40%
ASE Test Inc [Member] | Alto Enterprises Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	British Virgin Islands
Percentage of Ownership (%)	100.00%	100.00%
ASE Test Inc [Member] | Super Zone Holdings Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	Hong Kong
Percentage of Ownership (%)	100.00%	100.00%
ASE Holding Limited [Member] | ASE Test Limited ("ASE Test") [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	Singapore
Percentage of Ownership (%)	10.20%	10.20%
ASE Holding Limited [Member] | ASE Investment (Labuan) Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	Malaysia
Percentage of Ownership (%)	70.10%	70.10%
ASE Holding Limited [Member] | ASE Technology Partners, Limited [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company and was established in August 2021
Establishment and Operating Location	British Cayman Islands
Percentage of Ownership (%)	100.00%	0.00%
ASE Holding Limited [Member] | Integrated Solutions Enterprise Europe ("ITGEU")
Disclosure of subsidiaries [Line Items]
Main Business	Trading company, and was acquired in October 2021 (Note 29)
Establishment and Operating Location	Belgium
Percentage of Ownership (%)	100.00%	0.00%
J&R Holding Limited [Member] | Omniquest Industrial Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	British Virgin Islands
Percentage of Ownership (%)	8.40%	8.40%
J&R Holding Limited [Member] | ASE Test Limited ("ASE Test") [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	Singapore
Percentage of Ownership (%)	89.80%	89.80%
J&R Holding Limited [Member] | J&R Industrial Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in leasing equipment and investing activity
Establishment and Operating Location	R.O.C.
Percentage of Ownership (%)	100.00%	100.00%
J&R Holding Limited [Member] | ASE Japan Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors
Establishment and Operating Location	Japan
Percentage of Ownership (%)	100.00%	100.00%
J&R Holding Limited [Member] | ASE (U.S.) Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	After-sales service and sales support
Establishment and Operating Location	U.S.A.
Percentage of Ownership (%)	100.00%	100.00%
J&R Holding Limited [Member] | Global Advanced Packaging Technology Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	British Cayman Islands
Percentage of Ownership (%)	100.00%	100.00%
J&R Holding Limited [Member] | Suzhou ASEN Semiconductors Co., Ltd. ("ASEN") [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors (organizational adjustment through exchanged shares to Global Advanced Packaging Test (Hong Kong) Limited in September 2021)
Establishment and Operating Location	Suzhou, China
Percentage of Ownership (%)	0.00%	100.00%
J&R Holding Limited [Member] | Anstock Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Liquidated in June 2021
Establishment and Operating Location	British Cayman Islands
Percentage of Ownership (%)	0.00%	100.00%
J&R Holding Limited [Member] | Anstock II Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Liquidated in June 2021
Establishment and Operating Location	British Cayman Islands
Percentage of Ownership (%)	0.00%	100.00%
Innosource Limited Investor [Member] | Omniquest Industrial Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	British Virgin Islands
Percentage of Ownership (%)	20.60%	20.60%
Innosource Limited Investor [Member] | ASE (Shanghai) Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the production of substrates
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	8.50%	8.50%
Omniquest Industrial Limited [Member] | ASE Corporation [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	British Cayman Islands
Percentage of Ownership (%)	100.00%	100.00%
Alto Enterprises Limited [Member] | ASE (Kunshan) Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors
Establishment and Operating Location	Kun Shan, China
Percentage of Ownership (%)		22.90%
Alto Enterprises Limited [Member] | ASE Investment (Kun Shan) Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	Kun Shan, China
Percentage of Ownership (%)	85.90%	85.90%
Super Zone Holdings Limited [Member] | Advanced Semiconductor Engineering (China) Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors, after-sale services, advisory and lease of factory
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	100.00%	100.00%
ASE Investment Labuan Inc [Member] | ASE (Korea) Inc. ("ASE Korea") [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors
Establishment and Operating Location	Korea
Percentage of Ownership (%)	100.00%	100.00%
ASE Korea [Member] | ASE (Weihai) Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors (disposed to J&R Holding and organizational adjustment through exchanged shares from J&R Holding to GAPT (Hong Kong) Limited in October 2021)
Establishment and Operating Location	Shandong, China
Percentage of Ownership (%)	0.00%	100.00%
ASE Test [Member] | ASE Test Holdings, Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	British Cayman Islands
Percentage of Ownership (%)	100.00%	100.00%
ASE Test [Member] | ASE Holdings (Singapore) Pte. Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	Singapore
Percentage of Ownership (%)	100.00%	100.00%
ASE Test [Member] | ASE Singapore Pte. Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors
Establishment and Operating Location	Singapore
Percentage of Ownership (%)	100.00%	100.00%
ASE Test [Member] | ASE Investment (Labuan) Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	Malaysia
Percentage of Ownership (%)	29.90%	29.90%
ASE Test Holdings Ltd [Member] | ISE Labs, Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the testing of semiconductors
Establishment and Operating Location	U.S.A.
Percentage of Ownership (%)	100.00%	100.00%
ISE Labs Inc [Member] | ISE Services Inc [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in wafer procurement and customer product management services
Establishment and Operating Location	U.S.A.
Percentage of Ownership (%)	100.00%	100.00%
ASE Holdings (Singapore) Pte Ltd [Member] | ASE Electronics (M) Sdn. Bhd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors
Establishment and Operating Location	Malaysia
Percentage of Ownership (%)	100.00%	100.00%
Global Advanced Packaging Technology Limited [Member] | ASE Assembly & Test (Shanghai) Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors and leasing of properties
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	100.00%	100.00%
Global Advanced Packaging Technology Limited [Member] | ASE Advanced Semiconductor (Shanghai) Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors (disposed to ASEN in November 2021)
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	0.00%	100.00%
Global Advanced Packaging Technology Limited [Member] | GAPT Holding Limited [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company and was established in August 2021
Establishment and Operating Location	British Virgin Islands
Percentage of Ownership (%)		0.00%
ASE Assembly & Test (Shanghai) Limited [member] | ASE Investment (Kun Shan) Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	Kun Shan, China
Percentage of Ownership (%)	14.10%	14.10%
ASE Assembly & Test (Shanghai) Limited [member] | ISE Labs, China, Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the testing of semiconductor
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	100.00%	100.00%
ASE Assembly & Test (Shanghai) Limited [member] | Wuxi Tongzhi Microelectronics Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors
Establishment and Operating Location	Wuxi, China
Percentage of Ownership (%)	100.00%	100.00%
ASE Assembly & Test (Shanghai) Limited [member] | Shanghai Ding Hui Real Estate Development Co., Ltd. (DH) [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the development, construction and sale of real estate properties
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	60.00%	60.00%
DH [Member] | Shanghai Ding Qi Property Management Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the management of real estate properties
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	100.00%	100.00%
DH [Member] | Shanghai Ding Wei Real Estate Development Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the development, construction and leasing of real estate properties
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	100.00%	100.00%
DH [Member] | Shanghai Ding Yu Real Estate Development Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the development, construction and leasing of real estate properties
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	100.00%	100.00%
DH [Member] | Kun Shan Ding Hong Real Estate Development Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the development, construction and leasing of real estate properties
Establishment and Operating Location	Kun Shan, China
Percentage of Ownership (%)	100.00%	100.00%
DH [Member] | Shanghai Ding Xu Property Management Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the management of real estate properties
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	100.00%	100.00%
DH [Member] | Shanghai Dingyao Estate Development Co Ltd [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the management of real estate properties
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	100.00%	100.00%
DH [Member] | Shanghai Ding Fan Business Management Co Ltd [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the management of real estate properties (acquired from DW in November 2020)
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	100.00%	100.00%
ASE Investment Kun Shan Limited [Member] | ASE (Kunshan) Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors
Establishment and Operating Location	Kun Shan, China
Percentage of Ownership (%)		49.30%
ASE Corporation [Member] | ASE Mauritius Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	Mauritius
Percentage of Ownership (%)	100.00%	100.00%
ASE Corporation [Member] | ASE Labuan Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	Malaysia
Percentage of Ownership (%)	100.00%	100.00%
ASE Mauritius Inc [Member] | ASE (Kunshan) Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors
Establishment and Operating Location	Kun Shan, China
Percentage of Ownership (%)		27.80%
ASE Mauritius Inc [Member] | ASE (Shanghai) Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the production of substrates
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	91.50%	91.50%
ASE Labuan Inc [Member] | ASE Electronics Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the production of substrates
Establishment and Operating Location	R.O.C.
Percentage of Ownership (%)	100.00%	100.00%
ASE (Shanghai) Inc. [Member] | Shanghai Ding Hui Real Estate Development Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the development, construction and sale of real estate properties
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	40.00%	40.00%
ASE (Shanghai) Inc. [Member] | Advanced Semiconductor Engineering (HK) Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the trading of substrates
Establishment and Operating Location	Hong Kong
Percentage of Ownership (%)	100.00%	100.00%
ASE (Shanghai) Inc. [Member] | Universal Scientific Industrial (Shanghai) Co., Ltd. ("USISH") [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the designing, manufacturing and sales of electronic components
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	0.80%	0.80%
USIINC [Member] | Huntington Holdings International Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	British Virgin Islands
Percentage of Ownership (%)	100.00%	100.00%
Huntington Holdings International Co Ltd [Member] | Unitech Holdings International Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	British Virgin Islands
Percentage of Ownership (%)	100.00%	100.00%
Huntington Holdings International Co Ltd [Member] | Real Tech Holdings Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	British Virgin Islands
Percentage of Ownership (%)	100.00%	100.00%
Huntington Holdings International Co Ltd [Member] | Universal ABIT Holding Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	In the process of liquidation
Establishment and Operating Location	British Cayman Islands
Percentage of Ownership (%)	100.00%	100.00%
Real Tech Holdings Limited [Member] | USI Enterprise Limited ("USIE") [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the service of investment advisory and warehousing management
Establishment and Operating Location	Hong Kong
Percentage of Ownership (%)	100.00%	95.90%
USIE [Member] | USISH [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the designing, manufacturing and sales of electronic components
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	77.10%	76.60%
USISH [Member] | Universal Global Technology Co., Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	Hong Kong
Percentage of Ownership (%)	100.00%	100.00%
USISH [Member] | Universal Global Technology (Kunshan) Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the designing and manufacturing of electronic components
Establishment and Operating Location	Kun Shan, China
Percentage of Ownership (%)	100.00%	100.00%
USISH [Member] | Universal Global Technology (Shanghai) Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the processing and sales of computer and communication peripherals as well as business in import and export of goods and technology
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	100.00%	100.00%
USISH [Member] | USI Electronics (Shenzhen) Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design, manufacturing and sales of motherboards and computer peripherals
Establishment and Operating Location	Shenzhen, China
Percentage of Ownership (%)	50.00%	50.00%
USISH [Member] | Universal Global Technology (Huizhou) Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the research and manufacturing of new electronic applications, communications, computers and other electronics products and also provided auxiliary technical services as well as import and export services
Establishment and Operating Location	Huizhou, China
Percentage of Ownership (%)	100.00%	100.00%
USISH [Member] | Universal Global Electronics (Shanghai) Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the sales of electronic components and telecommunications equipment
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)	100.00%	100.00%
USISH [Member] | FINANCIERE AFG（FAFG ) [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	France
Percentage of Ownership (%)	10.40%	10.40%
Universal Global Technology Co Limited [Member] | USI America Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the manufacturing and processing of motherboards and wireless network communication and provision of related technical service
Establishment and Operating Location	U.S.A.
Percentage of Ownership (%)	100.00%	100.00%
Universal Global Technology Co Limited [Member] | Universal Global Industrial Co., Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in manufacturing, trading and investing activity
Establishment and Operating Location	Hong Kong
Percentage of Ownership (%)	100.00%	100.00%
Universal Global Technology Co Limited [Member] | Universal Scientific Industrial De Mexico S.A. De C.V. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the assembling of motherboards and computer components
Establishment and Operating Location	Mexico
Percentage of Ownership (%)	100.00%	100.00%
Universal Global Technology Co Limited [Member] | USI Japan Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the manufacturing and sales of computer peripherals, integrated chip and other related accessories
Establishment and Operating Location	Japan
Percentage of Ownership (%)	100.00%	100.00%
Universal Global Technology Co Limited [Member] | USI Electronics (Shenzhen) Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design, manufacturing and sales of motherboards and computer peripherals
Establishment and Operating Location	Shenzhen, China
Percentage of Ownership (%)	50.00%	50.00%
Universal Global Technology Co Limited [Member] | Universal Global Electronics Co., Ltd [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in accepting and outsourcing orders as well as sales of electronic components and service of technical advisory
Establishment and Operating Location	Hong Kong
Percentage of Ownership (%)	100.00%	100.00%
Universal Global Technology Co Limited [Member] | Universal Scientific Industrial (France) ("USIFR") [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in investing activities
Establishment and Operating Location	France
Percentage of Ownership (%)	100.00%	100.00%
Universal Global Technology Co Limited [Member] | UNIVERSAL SCIENTIFIC INDUSTRIAL (VIETNAM) CO., LTD [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in IC assembly for wearable devices and was established in July 2020.
Establishment and Operating Location	Vietnam
Percentage of Ownership (%)	100.00%	100.00%
UGTW [Member] | Universal Scientific Industrial Co., Ltd. ("USI") [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the manufacturing, processing and sales of computers, computer peripherals and related accessories
Establishment and Operating Location	R.O.C.
Percentage of Ownership (%)	100.00%	100.00%
Universal Global Electronics Co., Ltd. [Member] | Universal Scientific Industrial Poland Sp. z o.o. ("USIPL") [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components and new electronic applications.
Establishment and Operating Location	Poland
Percentage of Ownership (%)	100.00%	100.00%
Universal Global Electronics Co., Ltd. [Member] | USI Science and Technology (Shenzhen) Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design of electronic components, service of technical advisory; wholesale of electronic components and communication peripherals as well as business in import and export of goods and management of properties. Established in November 2020.
Establishment and Operating Location	Shenzhen, China
Percentage of Ownership (%)	100.00%	100.00%
Universal Scientific Industrial (France) [member] | FAFG [member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	France
Percentage of Ownership (%)	89.60%	89.60%
Universal Scientific Industrial (France) [member] | ASTEELFLASH GROUP [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company (disposed to FAFG in October 2021)
Establishment and Operating Location	France
Percentage of Ownership (%)	0.00%
FAFG [member] | ASTEELFLASH GROUP [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company (acquired 1 share from Universal Scientific Industrial (France) in October 2021)
Establishment and Operating Location	France
Percentage of Ownership (%)	100.00%	100.00%
FAFG [member] | MANUFACTURING POWER TUNISIA [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Tunisia
Percentage of Ownership (%)	0.10%	0.10%
FAFG [member] | ASTEELFLASH MEXICO S.A. de C.V. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Mexico
Percentage of Ownership (%)	0.10%	0.10%
ASTEELFLASH GROUP [member] | MANUFACTURING POWER TUNISIA [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Tunisia
Percentage of Ownership (%)	99.90%	99.90%
ASTEELFLASH GROUP [member] | ASTEELFLASH MEXICO S.A. de C.V. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Mexico
Percentage of Ownership (%)	99.90%	99.90%
ASTEELFLASH GROUP [member] | ASTEELFLASH (BEDFORD) LIMITED [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	United Kingdom
Percentage of Ownership (%)	100.00%	100.00%
ASTEELFLASH GROUP [member] | ASTEELFLASH FRANCE [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	France
Percentage of Ownership (%)	99.90%	99.90%
ASTEELFLASH GROUP [member] | ASTEELFLASH TUNISIE S.A. [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Tunisia
Percentage of Ownership (%)	100.00%	100.00%
ASTEELFLASH GROUP [member] | ASTEELFLASH HONG KONG LIMITED [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	Hong Kong
Percentage of Ownership (%)	100.00%	100.00%
ASTEELFLASH GROUP [member] | ASTEELFLASH GERMANY GmbH [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Germany
Percentage of Ownership (%)	100.00%	100.00%
ASTEELFLASH GROUP [member] | ASTEELFLASH US HOLDING CORP [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company
Establishment and Operating Location	U.S.A.
Percentage of Ownership (%)	100.00%	100.00%
ASTEELFLASH GROUP [member] | ASTEEL ELECTRONIQUE FOUCHANA [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH TUNISIE S.A. in June 2021)
Establishment and Operating Location	Tunisia
Percentage of Ownership (%)	0.00%
ASTEELFLASH GROUP [member] | AFERH TUNISIE [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the management, training and consulting of human resources
Establishment and Operating Location	Tunisia
Percentage of Ownership (%)	0.50%	0.50%
ASTEELFLASH GROUP [member] | ASTEEL ELECTRONICS MANUFACTURING SERVICES [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Tunisia
Percentage of Ownership (%)	0.10%	0.10%
ASTEELFLASH GROUP [member] | ASTEELFLASH PLZEN S.R.O. [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components (acquired from ASTEELFLASH GERMANY GmbH in April 2021)
Establishment and Operating Location	Czech Republic
Percentage of Ownership (%)	100.00%
ASTEELFLASH (BEDFORD) LIMITED [Member] | ASTEELFLASH TUNISIE S.A. [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Tunisia
ASTEELFLASH TECHNOLOGIE [Member] | ASTEELFLASH FRANCE [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	France
ASTEELFLASH FRANCE [Member] | ASTEELFLASH TUNISIE S.A. [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Tunisia
ASTEELFLASH FRANCE [Member] | ASTEEL ELECTRONIQUE FOUCHANA [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH TUNISIE S.A. in June 2021)
Establishment and Operating Location	Tunisia
Percentage of Ownership (%)	0.00%	94.20%
ASTEELFLASH FRANCE [Member] | ASTEEL ELECTRONICS MANUFACTURING SERVICES [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Tunisia
Percentage of Ownership (%)	99.90%	99.90%
ASTEELFLASH FRANCE [Member] | SCI CHASSET [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the management and operation of real estate properties and holding the ownership of real estate properties (Liquidated in July 2021)
Establishment and Operating Location	France
Percentage of Ownership (%)	0.00%	100.00%
ASTEELFLASH FRANCE [Member] | AFERH [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the management, training and consulting of human resources (Liquidated in July 2021)
Establishment and Operating Location	France
Percentage of Ownership (%)	0.00%	100.00%
ASTEELFLASH FRANCE [Member] | ASTEELFLASH TECHNOLOGIE [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in projection of plastic and the design and manufacturing of industrial components
Establishment and Operating Location	France
Percentage of Ownership (%)	100.00%	100.00%
ASTEELFLASH FRANCE [Member] | ASTEELFLASH BRETAGNE [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	France
Percentage of Ownership (%)	100.00%	100.00%
ASTEELFLASH TUNISIE S.A. [member] | ASTEEL ELECTRONIQUE TUNISIE [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components (merged by ASTEELFLASH TUNISIE S.A.in December 2021)
Establishment and Operating Location	Tunisia
Percentage of Ownership (%)	0.00%	100.00%
ASTEELFLASH TUNISIE S.A. [member] | ASTEEL ELECTRONIQUE FOUCHANA [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components (acquired from ASTEELFLASH GROUP, ASTEELFLASH FRANCE, Asteelflash Suzhou Co., Ltd. and ASTEELFLASH USA CORP.in June 2021 and merged by ASTEELFLASH TUNISIE S.A. in December 2021)
Establishment and Operating Location	Tunisia
AFERH [Member] | AFERH TUNISIE [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the management, training and consulting of organization and human resources
Establishment and Operating Location	Tunisia
Percentage of Ownership (%)	99.50%	99.50%
ASTEELFLASH HONG KONG LIMITED [Member] | Asteelflash Suzhou Co., Ltd.
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Suzhou, China
Percentage of Ownership (%)	100.00%	100.00%
Asteelflash Suzhou Co., Ltd. [member] | ASTEELFLASH TUNISIE S.A. [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Tunisia
Asteelflash Suzhou Co., Ltd. [member] | ASTEEL ELECTRONIQUE FOUCHANA [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH TUNISIE S.A. in June 2021)
Establishment and Operating Location	Tunisia
Percentage of Ownership (%)	0.00%
ASTEELFLASH GERMANY GmbH [member] | ASTEELFLASH TUNISIE S.A. [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Tunisia
ASTEELFLASH GERMANY GmbH [member] | ASTEELFLASH HERSFELD GmbH [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Germany
Percentage of Ownership (%)	100.00%	100.00%
ASTEELFLASH GERMANY GmbH [member] | ASTEELFLASH EBERBACH GmbH [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Germany
Percentage of Ownership (%)	100.00%	100.00%
ASTEELFLASH GERMANY GmbH [member] | ASTEELFLASH BONN GmbH [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Germany
Percentage of Ownership (%)	100.00%	100.00%
ASTEELFLASH GERMANY GmbH [member] | ASTEELFLASH SCHWANDORF GmbH [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Germany
Percentage of Ownership (%)	100.00%	100.00%
ASTEELFLASH GERMANY GmbH [member] | ASTEELFLASH PLZEN S.R.O. [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH GROUP in April 2021)
Establishment and Operating Location	Czech Republic
Percentage of Ownership (%)	0.00%	100.00%
ASTEELFLASH GERMANY GmbH [member] | ASTEELFLASH DESIGN SOLUTIONS HAMBOURG GmbH [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Germany
Percentage of Ownership (%)	100.00%	100.00%
ASTEELFLASH GERMANY GmbH [member] | EN ELECTRONICNETWORK SRL [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Romania
Percentage of Ownership (%)	100.00%	100.00%
ASTEELFLASH MEXICO S.A. de C.V. [member] | ASTEELFLASH TUNISIE S.A. [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Tunisia
ASTEELFLASH US HOLDING CORP. [member] | ASTEELFLASH USA CORP [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	U.S.A.
Percentage of Ownership (%)	100.00%	100.00%
ASTEELFLASH USA CORP. [member] | ASTEELFLASH TUNISIE S.A. [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components
Establishment and Operating Location	Tunisia
ASTEELFLASH USA CORP. [member] | ASTEEL ELECTRONIQUE FOUCHANA [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the design and manufacturing of electronic components (disposed to ASTEELFLASH TUNISIE S.A. in June 2021)
Establishment and Operating Location	Tunisia
Percentage of Ownership (%)	0.00%
SPIL [Member] | SPIL (B.V.I.) Holding Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in investing activities
Establishment and Operating Location	British Virgin Islands
Percentage of Ownership (%)	100.00%	100.00%
SPIL [Member] | Siliconware Investment Co., Ltd. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in investing activities
Establishment and Operating Location	R.O.C.
Percentage of Ownership (%)	100.00%	100.00%
SPIL (B.V.I.) Holding Limited [Member] | Siliconware USA, Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in marketing activities
Establishment and Operating Location	U.S.A.
Percentage of Ownership (%)	100.00%	100.00%
SPIL (B.V.I.) Holding Limited [Member] | SPIL (Cayman) Holding Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in investing activities
Establishment and Operating Location	British Cayman Islands
Percentage of Ownership (%)	100.00%	100.00%
SPIL (Cayman) Holding Limited [Member] | Siliconware Technology (Suzhou) Limited ("SZ") [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors
Establishment and Operating Location	Suzhou, China
Percentage of Ownership (%)	100.00%	100.00%
ASE Technology Partners, Limited [Member] | ASE Technology Acquisition Corporation [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Holding company and was established in August 2021
Establishment and Operating Location	British Cayman Islands
Percentage of Ownership (%)	100.00%	0.00%
GAPT Holding Limited [Member] | Global Advanced Packaging Test (Hongkong) Limited [Member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the trading of substrates and was established in August 2021
Establishment and Operating Location	Hong Kong
Percentage of Ownership (%)		0.00%
Global Advanced Packaging Test (Hongkong) Limited [Member] | ASE (Weihai) Inc. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors (acquired from J&R Holding in October 2021 through share exchange under restructure)
Establishment and Operating Location	Shandong, China
Percentage of Ownership (%)	0.00%
Global Advanced Packaging Test (Hongkong) Limited [Member] | Suzhou ASEN Semiconductors Co., Ltd. ("ASEN") [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors (acquired from J&R Holding in September 2021 through share exchange under restructure)
Establishment and Operating Location	Suzhou, China
Percentage of Ownership (%)	0.00%
ASEN [Member] | ASE Advanced Semiconductor (Shanghai) Limited [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the packaging and testing of semiconductors (acquired from Global Advanced Packaging Technology Limited in November 2021)
Establishment and Operating Location	Shanghai, China
Percentage of Ownership (%)		0.00%
Universal Global Technology Co., Limited [Member] | Universal Global Scientific Industrial Co., Ltd. ("UGTW") [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the manufacturing of components of telecommunication and cars and provision of related R&D services
Establishment and Operating Location	R.O.C.
Percentage of Ownership (%)	100.00%	100.00%
Universal Global Industrial Co., Limited [Member] | Universal Scientific Industrial De Mexico S.A. De C.V. [member]
Disclosure of subsidiaries [Line Items]
Main Business	Engaged in the assembling of motherboards and computer components
Establishment and Operating Location	Mexico

Cash and Cash Equivalents - Sum

Cash and Cash Equivalents - Summary of Cash and Cash Equivalents (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019TWD ($)	Dec. 31, 2018TWD ($)
Cash and cash equivalents [abstract]
Cash on hand	$ 5,638	$ 203	$ 6,073
Checking accounts and demand deposits	47,094,687	1,697,718	48,734,866
Cash equivalents (time deposits with original maturity of less than three months and repurchase agreements collateralized by bonds)	28,973,020	1,044,449	2,797,132
Cash and cash equivalents,total	$ 76,073,345	$ 2,742,370	$ 51,538,071	$ 1,857,897	$ 60,130,875	$ 51,518,436

Financial Instruments at Fair_3

Financial Instruments at Fair Value Through Profit or Loss - Summary of Financial Instruments at Fair Value Through Profit or Loss (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	$ 5,436,280	$ 195,973	$ 6,523,583
Current	2,933,446	105,748	4,342,605
Non-current	2,502,834	90,225	2,180,978
Financial liabilities held for trading	417,660	15,056	1,537,208
Swap contracts [member] | Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	85,629	3,087	99,312
Financial liabilities held for trading	360,797	13,006	1,448,972
Forward exchange contracts [member] | Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	23,373	843	122,511
Financial liabilities held for trading	56,863	2,050	9,020
Redemption option and put option of convertible bonds [member] | Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	8,463	305
Target redemption forward contracts [member] | Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	500	18
Financial liabilities held for trading			79,216
Quoted ordinary shares [member] | Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	2,683,193	96,726	4,064,438
Private-placement funds [member] | Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	1,322,686	47,682	1,124,754
Unquoted preferred shares [member] | Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	583,270	21,026	385,440
Contingent considerations [member] | Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	394,943	14,237	387,790
Open-end mutual funds [member] | Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	$ 334,223	$ 12,049	$ 339,338

Financial Instruments at Fair_4

Financial Instruments at Fair Value Through Profit or Loss - Summary of Outstanding Contracts Not Accounted for Hedge Accounting (Detail) € in Thousands, ₩ in Thousands, ¥ in Thousands, ¥ in Thousands, RM in Thousands, $ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2021CNY (¥)	Dec. 31, 2021JPY (¥)	Dec. 31, 2021KRW (₩)	Dec. 31, 2021EUR (€)	Dec. 31, 2021MYR (RM)	Dec. 31, 2021SGD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2020CNY (¥)	Dec. 31, 2020HKD ($)	Dec. 31, 2020JPY (¥)	Dec. 31, 2020KRW (₩)	Dec. 31, 2020EUR (€)	Dec. 31, 2020MYR (RM)	Dec. 31, 2020SGD ($)
Swap contracts [member] | Sell RMB/Buy US$ [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-01
Notional Amount			$ 409,000	¥ 2,617,518
Swap contracts [member] | Sell NT$/buy US$ [member]
Disclosure of detailed information about financial instruments [line items]
Notional Amount	$ 52,916,127	$ 51,140,082	1,903,000							$ 1,755,000
Swap contracts [member] | Sell NT$/buy US$ [member] | Bottom of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-01	2021-01
Swap contracts [member] | Sell NT$/buy US$ [member] | Top of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-12	2021-12
Swap contracts [member] | Sell US$/Buy RMB [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-02
Notional Amount			54,415	349,800						59,793	¥ 395,742
Swap contracts [member] | Sell US$/Buy RMB [member] | Bottom of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period		2021-01
Swap contracts [member] | Sell US$/Buy RMB [member] | Top of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period		2021-02
Swap contracts [member] | Sell US$/buy JPY [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-01	2021-01
Notional Amount			17,671		¥ 2,000,000					41,630			¥ 4,300,000
Swap contracts [member] | Sell US$/buy NT$ [member]
Disclosure of detailed information about financial instruments [line items]
Notional Amount	$ 15,845,090	$ 19,073,846	570,130							675,240
Swap contracts [member] | Sell US$/buy NT$ [member] | Bottom of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-01	2021-01
Swap contracts [member] | Sell US$/buy NT$ [member] | Top of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-04	2021-02
Swap contracts [member] | Sell US$/Buy KRW [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-01	2021-01
Notional Amount			37,500			₩ 44,418,750				30,000				₩ 33,066,000
Swap contracts [member] | Sell US/Buy HKD$ [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period		2021-02
Notional Amount										13,804		$ 107,000
Forward exchange contracts [member] | Sell RMB/Buy US$ [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-01	2021-01
Notional Amount			114,000	727,645						116,093	756,946
Forward exchange contracts [member] | Sell HKD/Buy US$ [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period		2021-01
Notional Amount										529		$ 4,100
Forward exchange contracts [member] | Sell NT$/buy US$ [member]
Disclosure of detailed information about financial instruments [line items]
Notional Amount	$ 3,465,805	$ 2,667,230	125,000							95,000
Forward exchange contracts [member] | Sell NT$/buy US$ [member] | Bottom of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-01	2021-01
Forward exchange contracts [member] | Sell NT$/buy US$ [member] | Top of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-03	2021-02
Forward exchange contracts [member] | Sell US$/Buy RMB [member]
Disclosure of detailed information about financial instruments [line items]
Notional Amount			265,000	1,701,695						363,000	¥ 2,385,500
Forward exchange contracts [member] | Sell US$/Buy RMB [member] | Bottom of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-01	2021-01
Forward exchange contracts [member] | Sell US$/Buy RMB [member] | Top of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-06	2021-04
Forward exchange contracts [member] | Sell US$/buy JPY [member]
Disclosure of detailed information about financial instruments [line items]
Notional Amount			94,747		10,789,851					100,076			¥ 10,405,845
Forward exchange contracts [member] | Sell US$/buy JPY [member] | Bottom of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-01	2021-01
Forward exchange contracts [member] | Sell US$/buy JPY [member] | Top of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-02	2021-04
Forward exchange contracts [member] | Sell US$/buy NT$ [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-01
Notional Amount	$ 277,735	$ 776,867	10,000							27,470
Forward exchange contracts [member] | Sell US$/buy NT$ [member] | Bottom of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period		2021-01
Forward exchange contracts [member] | Sell US$/buy NT$ [member] | Top of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period		2021-02
Forward exchange contracts [member] | Sell US$/Buy EUR [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-01	2021-01
Notional Amount			460				€ 407			1,607					€ 1,320
Forward exchange contracts [member] | Sell US$/Buy KRW [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period		2021-01
Notional Amount										16,000				₩ 17,575,300
Forward exchange contracts [member] | Sell US$/Buy MYR [member]
Disclosure of detailed information about financial instruments [line items]
Notional Amount			8,000					RM 33,430		24,000						RM 98,737
Forward exchange contracts [member] | Sell US$/Buy MYR [member] | Bottom of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-01	2021-01
Forward exchange contracts [member] | Sell US$/Buy MYR [member] | Top of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-02	2021-04
Forward exchange contracts [member] | Sell US$/Buy SGD [member]
Disclosure of detailed information about financial instruments [line items]
Notional Amount			16,900						$ 22,925	18,500							$ 24,868
Forward exchange contracts [member] | Sell US$/Buy SGD [member] | Bottom of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-01	2021-01
Forward exchange contracts [member] | Sell US$/Buy SGD [member] | Top of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-02	2021-04
Forward exchange contracts [member] | Sell RMBBuy JPY [Member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-01
Notional Amount				¥ 35,127	¥ 630,000
Target redemption forward contracts [member] | Sell EUR/Buy US$ [member]
Disclosure of detailed information about financial instruments [line items]
Notional Amount			$ 3,475				€ 2,982			$ 27,475					€ 23,279
Target redemption forward contracts [member] | Sell EUR/Buy US$ [member] | Bottom of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-04	2022-04
Target redemption forward contracts [member] | Sell EUR/Buy US$ [member] | Top of range [member]
Disclosure of detailed information about financial instruments [line items]
Maturity Period	2022-06

Financial Assets at Fair Valu_3

Financial Assets at Fair Value Through Other Comprehensive Income - Summary of Financial Assets at Fair Value Through Other Comprehensive Income (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Financial assets at fair value through other comprehensive income [abstract]
Investments in equity instruments at FVTOCI	$ 943,354	$ 34,007	$ 728,398
Investments in debt instruments at FVTOCI	1,076,458	38,805	1,012,736
Total	$ 2,019,812	$ 72,812	$ 1,741,134

Financial Assets at Fair Valu_4

Financial Assets at Fair Value Through Other Comprehensive Income - Summary of Investments in Equity Instruments at Fair Value Through Other Comprehensive Income (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items]
Investments in equity instruments at FVTOCI	$ 943,354	$ 34,007	$ 728,398
Unquoted ordinary shares [member]
Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items]
Investments in equity instruments at FVTOCI	820,779	29,588	567,377
Limited partnership [member]
Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items]
Investments in equity instruments at FVTOCI	9,206	332	9,692
Unquoted preferred shares [member]
Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items]
Investments in equity instruments at FVTOCI	11,245	405	$ 151,329
Quoted ordinary shares
Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items]
Investments in equity instruments at FVTOCI	$ 102,124	$ 3,682

Financial Assets at Fair Valu_5

Financial Assets at Fair Value Through Other Comprehensive Income - Summary of Investments in Debt Instruments at Fair Value Through Other Comprehensive Income (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Financial assets at fair value through other comprehensive income [line items]
Investments in debt instruments at FVTOCI	$ 1,076,458	$ 38,805	$ 1,012,736
Unsecured subordinate corporate bonds [member]
Financial assets at fair value through other comprehensive income [line items]
Investments in debt instruments at FVTOCI	$ 1,076,458	$ 38,805	$ 1,012,736

Financial Assets at Fair Valu_6

Financial Assets at Fair Value Through Other Comprehensive Income - Additional Information (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)Bonds	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Financial assets at fair value through other comprehensive income [line items]
Unsecured subordinate corporate bonds amount	$ 1,556,980	$ 56,128	$ 1,082,000
Unsecured subordinate corporate bonds [member]
Financial assets at fair value through other comprehensive income [line items]
Unsecured subordinate corporate bonds amount | $	$ 1,000
Number of bonds acquired | Bonds	1,000
Corporate bonds annual interest rate	3.50%	3.50%
Effective interest rate	3.20%	3.20%

Trade Receivables, Net - Summar

Trade Receivables, Net - Summary of Trade Receivables, Net (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of financial assets [Line Items]
Trade receivables	$ 109,369,478	$ 3,942,673	$ 91,207,576
At FVTOCI	6,092,462	219,627	626,413
Total trade receivable	115,462,210	4,162,300	91,833,989
Cost [member]
Disclosure of financial assets [Line Items]
Trade receivables	109,473,101	3,946,399	91,304,934
Allowance for doubtful debts [member]
Disclosure of financial assets [Line Items]
Trade receivables	$ 103,353	$ 3,726	$ 97,358

Trade Receivables, Net - Additi

Trade Receivables, Net - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2021
Bottom of range [member]
Disclosure of financial assets [Line Items]
Average credit terms	30 days
Top of range [member]
Disclosure of financial assets [Line Items]
Average credit terms	90 days

Trade Receivables, Net - Summ_2

Trade Receivables, Net - Summary of Loss Allowance of Trade Receivables Based on Group's Provision Matrix (Detail) - Trade receivables [member] $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of provision matrix [line items]
Gross carrying amount	$ 109,473,101	$ 3,946,399	$ 91,304,934
Loss allowance (Lifetime ECL)	(103,353)	(3,726)	(97,358)
Net Amount	$ 109,369,748	$ 3,942,673	$ 91,207,576
Not past due [member]
Disclosure of provision matrix [line items]
Expected credit loss rate	0.00%	0.00%	0.00%
Gross carrying amount	$ 105,538,390	$ 3,804,556	$ 86,820,792
Loss allowance (Lifetime ECL)	(18,062)	(651)	(18,911)
Net Amount	105,520,328	3,803,905	86,801,881
Less than 1 month [member]
Disclosure of provision matrix [line items]
Gross carrying amount	3,136,438	113,066	3,823,249
Loss allowance (Lifetime ECL)	(1,811)	(65)	(2,053)
Net Amount	$ 3,134,627	$ 113,001	$ 3,821,196
Less than 1 month [member] | Bottom of range [member]
Disclosure of provision matrix [line items]
Expected credit loss rate	0.00%	0.00%	0.00%
Less than 1 month [member] | Top of range [member]
Disclosure of provision matrix [line items]
Expected credit loss rate	10.00%	10.00%	10.00%
1 to 3 months [member]
Disclosure of provision matrix [line items]
Gross carrying amount	$ 609,695	$ 21,979	$ 557,487
Loss allowance (Lifetime ECL)	(22,785)	(821)	(20,629)
Net Amount	$ 586,910	$ 21,158	$ 536,858
1 to 3 months [member] | Bottom of range [member]
Disclosure of provision matrix [line items]
Expected credit loss rate	0.00%	0.00%	0.00%
1 to 3 months [member] | Top of range [member]
Disclosure of provision matrix [line items]
Expected credit loss rate	70.00%	70.00%	70.00%
More than 91 days [member]
Disclosure of provision matrix [line items]
Gross carrying amount	$ 99,118	$ 3,573	$ 92,873
Loss allowance (Lifetime ECL)	(46,337)	(1,671)	(45,232)
Net Amount	$ 52,781	$ 1,902	$ 47,641
More than 91 days [member] | Bottom of range [member]
Disclosure of provision matrix [line items]
Expected credit loss rate	1.00%	1.00%	1.00%
More than 91 days [member] | Top of range [member]
Disclosure of provision matrix [line items]
Expected credit loss rate	100.00%	100.00%	100.00%
Individually impaired [member]
Disclosure of provision matrix [line items]
Gross carrying amount	$ 89,460	$ 3,225	$ 10,533
Loss allowance (Lifetime ECL)	(14,358)	(518)	(10,533)
Net Amount	$ 75,102	$ 2,707	$ 0
Individually impaired [member] | Bottom of range [member]
Disclosure of provision matrix [line items]
Expected credit loss rate	0.00%	0.00%	50.00%
Individually impaired [member] | Top of range [member]
Disclosure of provision matrix [line items]
Expected credit loss rate	100.00%	100.00%	100.00%

Trade Receivables, Net - Summ_3

Trade Receivables, Net - Summary of Movements of Loss Allowance of Trade Receivables (Detail) - Trade receivables [member] $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of financial assets [Line Items]
Beginning balance	$ 97,358	$ 3,510	$ 136,497	$ 155,389
Net remeasurement of loss allowance	17,078	616	(55,742)	(38,277)
Reclassification	0	0	(6,970)	(5,877)
Acquisition through business combinations	0	0	32,460	25,553
Amounts written off	(399)	(14)	(3,944)	0
Disposal of subsidiaries	(4,637)	(167)
Effects of foreign currency exchange differences	(6,047)	(219)	(4,943)	(291)
Ending balance	$ 103,353	$ 3,726	$ 97,358	$ 136,497

Trade Receivables, Net - Summ_4

Trade Receivables, Net - Summary of Loss Allowance For Current Financial Assets At FVTOCI (Details) - Trade receivables [member] $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure For Loss Allowance For Current Financial Assets At FVTOCI [Line Items]
Gross carrying amount	$ 6,092,462	$ 219,627	$ 626,413
Loss allowance (Lifetime ECLs)	0	0
Net Amount	$ 6,092,462	$ 219,627	$ 626,413
Not past due [member]
Disclosure For Loss Allowance For Current Financial Assets At FVTOCI [Line Items]
Expected credit loss rate	0.00%	0.00%	0.00%
Gross carrying amount	$ 5,991,543	$ 215,989	$ 613,968
Loss allowance (Lifetime ECLs)	0	0
Net Amount	$ 5,991,543	$ 215,989	$ 613,968
Less than 1 month [member]
Disclosure For Loss Allowance For Current Financial Assets At FVTOCI [Line Items]
Expected credit loss rate	0.00%	0.00%	0.00%
Gross carrying amount	$ 9,415	$ 340	$ 9,874
Loss allowance (Lifetime ECLs)	0	0
Net Amount	$ 9,415	$ 340	$ 9,874
1 to 3 months [member]
Disclosure For Loss Allowance For Current Financial Assets At FVTOCI [Line Items]
Expected credit loss rate	0.00%	0.00%	0.00%
Gross carrying amount	$ 91,493	$ 3,298	$ 2,571
Loss allowance (Lifetime ECLs)	0	0
Net Amount	$ 91,493	$ 3,298	$ 2,571
More than 91 days [member]
Disclosure For Loss Allowance For Current Financial Assets At FVTOCI [Line Items]
Expected credit loss rate	0.00%	0.00%
Gross carrying amount	$ 11	$ 0
Loss allowance (Lifetime ECLs)	0	0
Net Amount	$ 11	$ 0
Individually impaired [member]
Disclosure For Loss Allowance For Current Financial Assets At FVTOCI [Line Items]
Expected credit loss rate	0.00%	0.00%
Gross carrying amount	$ 0	$ 0
Loss allowance (Lifetime ECLs)	0	0
Net Amount	$ 0	$ 0

Trade Receivables, Net - Trans

Trade Receivables, Net - Transfer of Financial Asset (Detail) € in Thousands, $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021EUR (€)	Dec. 31, 2021TWD ($)	Dec. 31, 2020EUR (€)	Dec. 31, 2020USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2021TWD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2020TWD ($)
Receivables Factoring Proceeds [Member] | BNP Paribas [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Assets that entity continues to recognise	€ 12,115		€ 16,691
Receivables Factoring Proceeds [Member] | HSBC [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Assets that entity continues to recognise			6,773
Receivables Factoring Proceeds [Member] | Citi Bank Taiwan Limited [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Assets that entity continues to recognise | $							$ 94,471
Receivables Factoring Proceeds [Member] | Standard Chartered Bank [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Assets that entity continues to recognise | $							$ 53,800
Receivables Factoring Proceeds [Member] | First Commercial Bank [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Assets that entity continues to recognise | $						$ 8,565		$ 6,879
Reclassified to Other Receivables [Member] | BNP Paribas [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Transferred to other receivables	12,081		15,315
Reclassified to Other Receivables [Member] | HSBC [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Transferred to other receivables			6,456
Advances Received But Unused [Member] | BNP Paribas [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Advances received	11,475		14,481
Advances Received But Unused [Member] | HSBC [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Advances received	€ 34		5,779
Advances Received Used [Member] | BNP Paribas [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Advances received			1,376
Advances Received Used [Member] | HSBC [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Advances received			€ 317
Advances Received Used [Member] | Citi Bank Taiwan Limited [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Advances received | $				$ 94,471
Advances Received Used [Member] | Standard Chartered Bank [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Advances received | $				$ 53,800
Advances Received Used [Member] | First Commercial Bank [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Advances received | $		$ 8,565			$ 6,879
Interest Rate On Advances Received Against Trade Receivables Sold [Member] | BNP Paribas [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Interest rates on advances received	0.80%	0.80%	0.80%	0.80%	0.80%
Interest Rate On Advances Received Against Trade Receivables Sold [Member] | HSBC [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Interest rates on advances received			1.45%	1.45%	1.45%
Interest Rate On Advances Received Against Trade Receivables Sold [Member] | Citi Bank Taiwan Limited [Member] | Maximum [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Interest rates on advances received			0.95%	0.95%	0.95%
Interest Rate On Advances Received Against Trade Receivables Sold [Member] | Citi Bank Taiwan Limited [Member] | Minimum [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Interest rates on advances received			0.84%	0.84%	0.84%
Interest Rate On Advances Received Against Trade Receivables Sold [Member] | Standard Chartered Bank [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Interest rates on advances received			0.91%	0.91%	0.91%
Interest Rate On Advances Received Against Trade Receivables Sold [Member] | First Commercial Bank [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Interest rates on advances received	1.95%	1.95%	1.95%	1.95%	1.95%

Trade Receivables, Net - Tra_2

Trade Receivables, Net - Transfer of Financial Asset (Parenthetical) (Detail) - TWD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Citi Bank Taiwan Limited [Member]
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Promissory notes issued	$ 2,000	$ 2,000

Inventories - Summary of Invent

Inventories - Summary of Inventories (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Classes of current inventories [abstract]
Finished goods	$ 8,454,783	$ 304,787	$ 8,822,632
Work in process	7,950,743	286,617	6,856,405
Raw materials	46,978,647	1,693,534	29,428,008
Supplies	3,339,042	120,369	2,691,779
Raw materials and supplies in transit	1,109,766	40,006	791,610
Inventories	$ 67,832,981	$ 2,445,313	$ 48,590,434

Inventories - Additional Inform

Inventories - Additional Information (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Classes of current inventories [abstract]
Cost of inventories recognized as operating costs	$ 458,345,579	$ 16,522,912	$ 398,068,260	$ 347,877,603
Write-downs of inventories	$ 647,946	$ 23,358	$ 1,493,793	$ 452,134

Inventories Related to Real E_3

Inventories Related to Real Estate Business - Summary of Inventories Related to Real Estate Business (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of detailed information about property, plant and equipment [Line Items]
Inventories related to real estate business	$ 5,412,114	$ 195,102	$ 13,471,645
Land and buildings held for sale [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Inventories related to real estate business	667,630	24,067	625,791
Construction in progress and machinery in transit [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Inventories related to real estate business	2,956,958	106,596	11,058,328
Land held for construction [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Inventories related to real estate business	$ 1,787,526	$ 64,439	$ 1,787,526

Inventories Related to Real E_4

Inventories Related to Real Estate Business - Additional Information (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Sep. 30, 2021TWD ($)	Sep. 30, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of detailed information about property, plant and equipment [Line Items]
Inventories related to real estate business expected to be recovered longer than twelve months	$ 5,412,114	$ 195,102			$ 13,471,645
Land Held For Construction [member] | Construction in progress [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Inventories related to real estate business expected to be recovered longer than twelve months			$ 9,722,579	$ 350,490

Other Financial Assets - Summar

Other Financial Assets - Summary of Other Financial Assets (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of financial assets [Line Items]
Other financial assets	$ 1,556,980	$ 56,128	$ 1,082,000
Current	140,857	5,078	551,655
Non-current	1,416,123	51,050	530,345
Pledged time deposits [member]
Disclosure of financial assets [Line Items]
Other financial assets	415,065	14,963	367,550
Guaranty deposits [member]
Disclosure of financial assets [Line Items]
Other financial assets	1,007,651	36,325	516,505
Time deposits with original maturity over three months [member]
Disclosure of financial assets [Line Items]
Other financial assets	60,499	2,181	35,988
Others [member]
Disclosure of financial assets [Line Items]
Other financial assets	$ 73,765	$ 2,659	$ 161,957

Investments Accounted for Usi_3

Investments Accounted for Using the Equity Method - Summary of Investments Accounted for Using the Equity Method (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Investments in subsidiaries, joint ventures and associates [abstract]
Investments in associates	$ 16,500,670	$ 594,833	$ 12,335,239
Investments in joint ventures	495,930	17,878	471,434
Investments accounted for using the equity method	$ 16,996,600	$ 612,711	$ 12,806,673	$ 12,085,207

Investments Accounted for Usi_4

Investments Accounted for Using the Equity Method - Summary of Investments in Associates Accounted for Using the Equity Method (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2021USD ($)
Disclosure of associates and joint ventures [line items]
Investments in associates	$ 16,500,670	$ 12,335,239	$ 594,833
Yann Yuan Investment Co., Ltd. [member]
Disclosure of associates and joint ventures [line items]
Main Business	Engaged in investing activities
Operating Location	R.O.C.
Percentages of ownership held by the Group	29.45%	32.21%
ChipMOS Technologies Inc. [member]
Disclosure of associates and joint ventures [line items]
Main Business	Engaged in the packaging and testing of semiconductors
Operating Location	R.O.C.
Percentages of ownership held by the Group	10.85%	10.85%
M-Universe Investments Pte. Ltd. [member]
Disclosure of associates and joint ventures [line items]
Main Business	Investment company
Operating Location	Singapore
Percentages of ownership held by the Group	42.23%	42.23%
Hung Ching Development & Construction Co. [member]
Disclosure of associates and joint ventures [line items]
Main Business	Engaged in the development, construction and leasing of real estate properties
Operating Location	R.O.C.
Percentages of ownership held by the Group	26.22%	26.22%
Hung Ching Kwan Co. [member]
Disclosure of associates and joint ventures [line items]
Main Business	Engaged in the leasing of real estate properties
Operating Location	R.O.C.
Percentages of ownership held by the Group	27.31%	27.31%
Deca Technologies Inc. [member]
Disclosure of associates and joint ventures [line items]
Main Business	Holding company with group engaged in the development of wafer level packaging and interconnect technology
Operating Location	U.S.A.
Percentages of ownership held by the Group	17.85%	17.85%
CHIPLETZ [Member]
Disclosure of associates and joint ventures [line items]
Main Business	Fabless substrate design house
Operating Location	U.S.A.
Percentages of ownership held by the Group	20.82%
Cost [member]
Disclosure of associates and joint ventures [line items]
Investments in associates before deferred gain on transfer of land	$ 16,800,819	$ 12,635,388	605,653
Cost [member] | Yann Yuan Investment Co., Ltd. [member]
Disclosure of associates and joint ventures [line items]
Investments in associates before deferred gain on transfer of land	9,873,978	6,670,035	355,947
Cost [member] | ChipMOS Technologies Inc. [member]
Disclosure of associates and joint ventures [line items]
Investments in associates before deferred gain on transfer of land	2,717,250	2,406,843	97,954
Cost [member] | M-Universe Investments Pte. Ltd. [member]
Disclosure of associates and joint ventures [line items]
Investments in associates before deferred gain on transfer of land	1,859,542	1,848,588	67,035
Cost [member] | Hung Ching Development & Construction Co. [member]
Disclosure of associates and joint ventures [line items]
Investments in associates before deferred gain on transfer of land	1,828,921	1,352,760	65,931
Cost [member] | Hung Ching Kwan Co. [member]
Disclosure of associates and joint ventures [line items]
Investments in associates before deferred gain on transfer of land	258,757	270,087	9,328
Cost [member] | Deca Technologies Inc. [member]
Disclosure of associates and joint ventures [line items]
Investments in associates before deferred gain on transfer of land	51,434	87,075	1,854
Cost [member] | CHIPLETZ [Member]
Disclosure of associates and joint ventures [line items]
Investments in associates before deferred gain on transfer of land	210,937		7,604
Deferred gain on transfer of land [member]
Disclosure of associates and joint ventures [line items]
Investments in associates	$ 300,149	$ 300,149	$ 10,820

Investments Accounted for Usi_5

Investments Accounted for Using the Equity Method - Additional Information (Detail) $ in Thousands, $ in Thousands	Jun. 30, 2021	Mar. 31, 2021USD ($)	Mar. 31, 2019	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of Investments Accounted for Using Equity Method [line Items]
Investments accounted for using equity method				$ 16,996,600	$ 612,711	$ 12,806,673	$ 12,085,207
CHIPLETZ [Member]
Disclosure of Investments Accounted for Using Equity Method [line Items]
Proportion of ownership interest in associate				20.82%
ISE Labs, Inc [Member] | CHIPLETZ [Member]
Disclosure of Investments Accounted for Using Equity Method [line Items]
Proportion of ownership interest in associate		20.82%
Investments accounted for using equity method		$ 8,000
SUMA-USI Electronics Co., Ltd. [member]
Disclosure of Investments Accounted for Using Equity Method [line Items]
Percentage of ownership interest in joint venture			49.00%
YANN YUAN INVESTMENT CO., LTD [member]
Disclosure of Investments Accounted for Using Equity Method [line Items]
Percentage of Ownership (%)	29.45%

Investments Accounted for Usi_6

Investments Accounted for Using the Equity Method - Summary of Fair Values of Investments in Associates with Available Published Price Quotation (Detail) - Level 1 of fair value hierarchy [member] $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Hung Ching Development & Construction Co. [member]
Disclosure of associates and joint ventures [line items]
Fair value of investments in associates with available published price quotation	$ 2,141,249	$ 77,190	$ 1,317,692
ChipMos Technologies Inc [member]
Disclosure of associates and joint ventures [line items]
Fair value of investments in associates with available published price quotation	$ 3,835,045	$ 138,250	$ 2,710,572

Investments Accounted for Usi_7

Investments Accounted for Using the Equity Method - Summary of Aggregate Information of Associates that are Not Individually Material (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of associates and joint ventures [line items]
Net income	$ 62,249,997	$ 2,244,050	$ 28,651,900	$ 18,268,565
Other comprehensive income	406,016	14,637	495,313	(4,370,611)
Total comprehensive income	62,656,013	2,258,687	29,147,213	13,897,954
Associates that are not individually material [member]
Disclosure of associates and joint ventures [line items]
Net income	872,697	31,460	545,833	321,413
Other comprehensive income	3,624,403	130,656	2,784,094	1,401,453
Total comprehensive income	$ 4,497,100	$ 162,116	$ 3,329,927	$ 1,722,866

Investments Accounted for Usi_8

Investments Accounted for Using the Equity Method - Summary of Investments in joint ventures Accounted for using the Equity Method (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2021USD ($)
Disclosure of joint ventures [line items]
Carrying Amount	$ 495,930	$ 471,434	$ 17,878
SUMA-USI Electronics Co., Ltd [member]
Disclosure of joint ventures [line items]
Main Business	Engaged in the design and manufacturing of electronic products
Operating Location	China
Carrying Amount	$ 495,930	$ 471,434	$ 17,878
Percentages of ownership	49.00%	49.00%

Investments Accounted for Usi_9

Investments Accounted for Using the Equity Method - Summary of Aggregate Information of the Joint Venture that is Not Individually Material (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of joint ventures [line items]
Net income (loss)	$ 62,249,997	$ 2,244,050	$ 28,651,900	$ 18,268,565
Other comprehensive income (loss)	406,016	14,637	495,313	(4,370,611)
Total comprehensive income (loss)	62,656,013	2,258,687	29,147,213	13,897,954
Joint venture that is not individually material [member]
Disclosure of joint ventures [line items]
Net income (loss)	27,003	973	1,780	(139,137)
Other comprehensive income (loss)			3,881	(3,169)
Total comprehensive income (loss)	$ 27,003	$ 973	$ 5,661	$ (142,306)

Property, Plant and Equipment -

Property, Plant and Equipment - Summary of Property, Plant and Equipment (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of detailed information about property, plant and equipment [Line Items]
Beginning balance	$ 234,365,397
Depreciation expense	48,604,160	$ 1,752,133	$ 46,016,548	$ 45,240,667
Additions	74,417,541	2,682,681	59,024,201	63,073,887
Ending balance	239,867,550	8,646,992	234,365,397
Cost [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Beginning balance	616,363,382	22,219,299	576,444,907	535,004,044
Additions	74,417,541	2,682,681	59,024,201	63,073,887
Disposals	(13,839,233)	(498,890)	(15,730,635)	(22,630,764)
Disposal of subsidiaries	(48,138,060)	(1,735,330)	(8,127,308)
Reclassification	(4,807,434)	(173,304)	538,074	745,331
Acquisition through business combinations	41,526	1,497	7,069,740	7,034,875
Effect of foreign currency exchange differences	(4,843,568)	(174,606)	(2,855,597)	(6,782,466)
Ending balance	619,194,154	22,321,347	616,363,382	576,444,907
Accumulated depreciation, amortisation and impairment [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Beginning balance	381,997,985	13,770,655	344,351,580	320,688,535
Depreciation expense	48,604,160	1,752,133	46,016,548	45,240,667
Impairment losses recognized	126,766	4,571	992,273	201,006
Disposals	(12,782,153)	(460,784)	(11,006,578)	(22,024,853)
Disposal of subsidiaries	(31,444,931)	(1,133,560)	(580,895)
Reclassification	(3,800,474)	(137,004)	311,848	294,232
Acquisition through business combinations	3,760	137	4,187,020	4,465,048
Effect of foreign currency exchange differences	(3,378,509)	(121,793)	(2,273,811)	(4,513,055)
Ending balance	379,326,604	13,674,355	381,997,985	344,351,580
Land [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Beginning balance	10,457,960
Ending balance	11,530,540	415,665	10,457,960
Land [member] | Cost [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Beginning balance	10,457,960	376,999	10,333,822	10,165,969
Additions	1,126,012	40,592
Disposals	(2,400)	(86)
Reclassification	393	14
Acquisition through business combinations			167,136	189,111
Effect of foreign currency exchange differences	(51,425)	(1,854)	(42,998)	(21,258)
Ending balance	11,530,540	415,665	10,457,960	10,333,822
Buildings and improvements [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Beginning balance	82,813,857
Ending balance	79,273,937	2,857,748	82,813,857
Buildings and improvements [member] | Cost [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Beginning balance	158,812,500	5,725,036	153,972,960	141,708,011
Additions	2,718,507	98,000	86,409	806,844
Disposals	(659,833)	(23,786)	(365,758)	(983,690)
Disposal of subsidiaries	(12,344,067)	(444,992)	(3,665,811)
Reclassification	5,038,562	181,635	7,367,875	13,601,469
Acquisition through business combinations	5,284	190	1,680,497	1,044,383
Effect of foreign currency exchange differences	(929,254)	(33,499)	(263,672)	(2,204,057)
Ending balance	152,641,699	5,502,584	158,812,500	153,972,960
Buildings and improvements [member] | Accumulated depreciation, amortisation and impairment [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Beginning balance	75,998,643	2,739,677	68,563,380	62,744,074
Depreciation expense	7,620,561	274,714	7,401,223	6,989,392
Impairment losses recognized	15,915	574		78,562
Disposals	(565,551)	(20,388)	(300,832)	(881,149)
Disposal of subsidiaries	(5,369,867)	(193,579)	(153,002)
Reclassification	(3,924,490)	(141,474)	3,462	210,558
Acquisition through business combinations	241	9	548,190	445,682
Effect of foreign currency exchange differences	(407,690)	(14,697)	(63,778)	(1,023,739)
Ending balance	73,367,762	2,644,836	75,998,643	68,563,380
Machinery and equipment1 [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Beginning balance	122,539,797
Ending balance	128,202,516	4,621,577	122,539,797
Machinery and equipment1 [member] | Cost [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Beginning balance	416,368,479	15,009,678	376,745,448	353,838,390
Additions	1,332,497	48,035	695,561	413,008
Disposals	(10,999,274)	(396,513)	(12,818,849)	(19,139,634)
Disposal of subsidiaries	(33,309,236)	(1,200,765)	(3,223,448)
Reclassification	53,856,444	1,941,473	52,980,977	41,302,651
Acquisition through business combinations	28,282	1,020	4,445,789	5,507,315
Effect of foreign currency exchange differences	(3,788,594)	(136,575)	(2,456,999)	(5,176,282)
Ending balance	423,488,598	15,266,353	416,368,479	376,745,448
Machinery and equipment1 [member] | Accumulated depreciation, amortisation and impairment [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Beginning balance	293,828,682	10,592,238	263,748,778	245,750,420
Depreciation expense	39,147,076	1,411,214	36,373,712	35,747,308
Impairment losses recognized	105,815	3,815	981,535	102,056
Disposals	(10,151,428)	(365,949)	(8,306,990)	(18,640,266)
Disposal of subsidiaries	(24,974,206)	(900,296)	(345,834)
Reclassification	142,234	5,127	497,230	83,777
Acquisition through business combinations	1,067	39	3,049,895	4,000,338
Effect of foreign currency exchange differences	(2,813,158)	(101,412)	(2,169,644)	(3,294,855)
Ending balance	295,286,082	10,644,776	293,828,682	263,748,778
Other equipment [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Beginning balance	4,700,318
Ending balance	3,928,284	141,610	4,700,318
Other equipment [member] | Cost [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Beginning balance	16,870,978	608,182	18,755,116	18,380,122
Additions	135,439	4,883	47,137	76,671
Disposals	(2,144,766)	(77,317)	(2,419,423)	(2,507,440)
Disposal of subsidiaries	(1,247,326)	(44,965)	(445,506)
Reclassification	1,181,455	42,590	222,066	3,062,838
Acquisition through business combinations	3,108	112	722,490	43,611
Effect of foreign currency exchange differences	(197,844)	(7,132)	(10,902)	(300,686)
Ending balance	14,601,044	526,353	16,870,978	18,755,116
Other equipment [member] | Accumulated depreciation, amortisation and impairment [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Beginning balance	12,170,660	438,740	12,039,422	12,194,041
Depreciation expense	1,836,523	66,205	2,241,613	2,503,967
Impairment losses recognized	5,036	182	10,738	20,388
Disposals	(2,065,174)	(74,447)	(2,398,756)	(2,503,438)
Disposal of subsidiaries	(1,100,858)	(39,685)	(82,059)
Reclassification	(18,218)	(657)	(188,844)	(103)
Acquisition through business combinations	2,452	89	588,935	19,028
Effect of foreign currency exchange differences	(157,661)	(5,684)	(40,389)	(194,461)
Ending balance	10,672,760	384,743	12,170,660	12,039,422
Construction in progress and machinery under installation [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Beginning balance	13,853,465
Ending balance	16,932,273	610,392	13,853,465
Construction in progress and machinery under installation [member] | Cost [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Beginning balance	13,853,465	499,404	16,637,561	10,911,552
Additions	69,105,086	2,491,171	58,195,094	61,777,364
Disposals	(32,960)	(1,188)	(126,605)
Disposal of subsidiaries	(1,237,431)	(44,608)	(792,543)
Reclassification	(64,884,288)	(2,339,016)	(60,032,844)	(57,221,627)
Acquisition through business combinations	4,852	175	53,828	250,455
Effect of foreign currency exchange differences	123,549	4,454	(81,026)	919,817
Ending balance	$ 16,932,273	$ 610,392	$ 13,853,465	$ 16,637,561

Property, Plant and Equipment_2

Property, Plant and Equipment - Additional Information (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Accumulated depreciation, amortisation and impairment [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Impairment losses recognized property plant "and" equipment	$ 126,766	$ 4,571	$ 992,273	$ 201,006

Property, Plant and Equipment_3

Property, Plant and Equipment - Summary of Property, Plant and Equipment Depreciated Useful Lives (Detail) - Buildings and improvements [member]	12 Months Ended
	Dec. 31, 2021
Bottom of range [member] | Main plant buildings [Member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Property, plant and equipment useful lives	10
Bottom of range [member] | Cleanrooms [Member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Property, plant and equipment useful lives	10
Bottom of range [member] | Others [Member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Property, plant and equipment useful lives	3
Bottom of range [member] | Machinery and equipment1 [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Property, plant and equipment useful lives	2
Bottom of range [member] | Other equipment [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Property, plant and equipment useful lives	2
Top of range [member] | Main plant buildings [Member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Property, plant and equipment useful lives	55
Top of range [member] | Cleanrooms [Member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Property, plant and equipment useful lives	20
Top of range [member] | Others [Member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Property, plant and equipment useful lives	20
Top of range [member] | Machinery and equipment1 [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Property, plant and equipment useful lives	10
Top of range [member] | Other equipment [member]
Disclosure of detailed information about property, plant and equipment [Line Items]
Property, plant and equipment useful lives	20

Lease Arrangements - Summary of

Lease Arrangements - Summary of Right-of-Use Assets (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)	Dec. 31, 2021USD ($)
Disclosure of quantitative information about right-of-use assets [line items]
Carrying amounts	$ 10,680,262		$ 8,741,807		$ 385,013
Additions to right-of-use assets	3,239,770	$ 116,791	702,996	$ 824,268
Depreciation charge for right-of-use assets	1,114,950	40,193	946,880	1,055,458
Land [member]
Disclosure of quantitative information about right-of-use assets [line items]
Carrying amounts	6,093,518		5,961,974		219,666
Depreciation charge for right-of-use assets	509,746	18,376	370,458	307,708
Buildings and improvements [member]
Disclosure of quantitative information about right-of-use assets [line items]
Carrying amounts	3,663,682		2,548,838		132,072
Depreciation charge for right-of-use assets	217,674	7,847	214,682	215,301
Machinery and equipment [member]
Disclosure of quantitative information about right-of-use assets [line items]
Carrying amounts	880,443		181,065		31,739
Depreciation charge for right-of-use assets	356,052	12,835	335,039	507,443
Other equipment [member]
Disclosure of quantitative information about right-of-use assets [line items]
Carrying amounts	42,619		49,930		$ 1,536
Depreciation charge for right-of-use assets	$ 31,478	$ 1,135	$ 26,701	$ 25,006

Lease Arrangements - Summary _2

Lease Arrangements - Summary of Lease Liabilities (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Lease liabilities [abstract]
Current	$ 809,536	$ 29,183	$ 774,444
Non-current	$ 6,590,348	$ 237,576	$ 5,101,386

Lease Arrangements - Summary _3

Lease Arrangements - Summary of the Group's Lease Liabilities are Mainly From Land and Buildings and Improvements. Range of Discount Rate for Lease Liabilities (Detail)	Dec. 31, 2021	Dec. 31, 2020
Land [member] | Bottom of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Discount Rate For Lease Liabilities	0.54%	0.54%
Land [member] | Top of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Discount Rate For Lease Liabilities	8.00%	8.00%
Buildings and improvements [member] | Bottom of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Discount Rate For Lease Liabilities	0.45%	0.54%
Buildings and improvements [member] | Top of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Discount Rate For Lease Liabilities	8.84%	8.84%

Lease Arrangements - Additional

Lease Arrangements - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2021
Land [member] | Bottom of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Lease Term	1 year
Land [member] | Top of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Lease Term	53 years
Buildings [member] | Bottom of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Lease Term	1 year
Buildings [member] | Top of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Lease Term	29 years

Lease Arrangements - Summary _4

Lease Arrangements - Summary of Other Related Lease Information (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of detailed information about property, plant and equipment [abstract]
Expenses relating to short-term leases	$ 814,235	$ 29,352	$ 682,142
Expenses relating to low-value assets leases	5,080	183	5,433
Expenses relating to variable lease payments not included in the measurement of lease liabilities	61,141	2,204	43,112
Total cash outflow for leases	$ 2,909,157	$ 104,872	$ 1,854,456

Investment Properties - Summary

Investment Properties - Summary of Investment Properties (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of detailed information about investment property [line items]
Beginning balance	$ 12,538,083		$ 12,854,071
Depreciation expenses	751,047	$ 27,074	562,260	$ 594,110
Ending balance	22,144,787	798,298	12,538,083	12,854,071
Land [member]
Disclosure of detailed information about investment property [line items]
Beginning balance	35,965		35,965
Ending balance	35,572	1,282	35,965	35,965
Buildings and improvements [member]
Disclosure of detailed information about investment property [line items]
Beginning balance	6,480,338		6,737,798
Ending balance	13,103,952	472,385	6,480,338	6,737,798
Right-of-use assets [member]
Disclosure of detailed information about investment property [line items]
Beginning balance	6,021,780		6,080,308
Ending balance	9,005,263	324,631	6,021,780	6,080,308
Cost [member]
Disclosure of detailed information about investment property [line items]
Beginning balance	14,597,683	526,232	14,314,126	15,337,702
Additions			6,352	2,532
Disposals	(5,350)	(193)	(1,902)	(1,843)
Disposal of subsidiaries	(1,377,599)	(49,661)
Reclassification	13,215,879	476,420	42,317	(511,199)
Effects of foreign currency exchange differences	23,735	856	236,790	(513,066)
Ending balance	26,454,348	953,654	14,597,683	14,314,126
Cost [member] | Land [member]
Disclosure of detailed information about investment property [line items]
Beginning balance	35,965	1,296	35,965	35,965
Reclassification	(393)	(14)
Effects of foreign currency exchange differences	0
Ending balance	35,572	1,282	35,965	35,965
Cost [member] | Buildings and improvements [member]
Disclosure of detailed information about investment property [line items]
Beginning balance	7,822,805	282,005	7,710,369	8,409,790
Additions			6,352	2,532
Disposals	(5,350)	(193)	(1,902)	(1,843)
Disposal of subsidiaries	(1,290,187)	(46,510)
Reclassification	9,818,133	353,934	(3,884)	(490,130)
Effects of foreign currency exchange differences	30,697	1,107	111,870	(209,980)
Ending balance	16,376,098	590,343	7,822,805	7,710,369
Cost [member] | Right-of-use assets [member]
Disclosure of detailed information about investment property [line items]
Beginning balance	6,738,913	242,931	6,567,792	6,891,947
Disposal of subsidiaries	(87,412)	(3,151)
Reclassification	3,398,139	122,500	46,201	(21,069)
Effects of foreign currency exchange differences	(6,962)	(251)	124,920	(303,086)
Ending balance	10,042,678	362,029	6,738,913	6,567,792
Accumulated depreciations [member]
Disclosure of detailed information about investment property [line items]
Beginning balance	2,059,600	74,247	1,460,055	1,000,098
Depreciation expenses	751,047	27,074	562,260	594,110
Disposals	(3,671)	(132)	(1,293)	(1,240)
Disposal of subsidiaries	(590,349)	(21,282)
Reclassification	2,093,115	75,455	9,119	(209,912)
Effects of foreign currency exchange differences	(181)	(6)	29,459	76,999
Ending balance	4,309,561	155,356	2,059,600	1,460,055
Accumulated depreciations [member] | Buildings and improvements [member]
Disclosure of detailed information about investment property [line items]
Beginning balance	1,342,467	48,395	972,571	707,376
Depreciation expenses	482,625	17,398	353,048	377,536
Disposals	(3,671)	(132)	(1,293)	(1,240)
Disposal of subsidiaries	(570,403)	(20,563)
Reclassification	2,014,201	72,610	(1,498)	(210,455)
Effects of foreign currency exchange differences	6,927	250	19,639	99,354
Ending balance	3,272,146	117,958	1,342,467	972,571
Accumulated depreciations [member] | Right-of-use assets [member]
Disclosure of detailed information about investment property [line items]
Beginning balance	717,133	25,852	487,484	292,722
Depreciation expenses	268,422	9,676	209,212	216,574
Disposal of subsidiaries	(19,946)	(719)
Reclassification	78,914	2,845	10,617	543
Effects of foreign currency exchange differences	(7,108)	(256)	9,820	(22,355)
Ending balance	$ 1,037,415	$ 37,398	$ 717,133	$ 487,484

Investment Properties - Additio

Investment Properties - Additional Information (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of detailed information about investment property [line items]
Adjustment to rent income	$ 3,865	$ 139	$ 54,139
Bottom of range [member]
Disclosure of detailed information about investment property [line items]
Operating lease Term	1 year	1 year
Top of range [member]
Disclosure of detailed information about investment property [line items]
Operating lease Term	20 years	20 years

Investment Properties - Summa_2

Investment Properties - Summary of Maturity Analysis Of Operating Lease Payments (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of detailed information about investment property [line items]
Undiscounted operating lease payments to be received	$ 9,500,632	$ 342,489	$ 3,424,290
Year 1 [member]
Disclosure of detailed information about investment property [line items]
Undiscounted operating lease payments to be received	1,693,659	61,055	880,929
Year 2 [member]
Disclosure of detailed information about investment property [line items]
Undiscounted operating lease payments to be received	1,405,450	50,666	688,123
Year 3 [member]
Disclosure of detailed information about investment property [line items]
Undiscounted operating lease payments to be received	1,210,891	43,651	471,966
Year 4 [member]
Disclosure of detailed information about investment property [line items]
Undiscounted operating lease payments to be received	1,019,498	36,752	383,307
Year 5 [member]
Disclosure of detailed information about investment property [line items]
Undiscounted operating lease payments to be received	929,609	33,511	335,706
Year 6 onwards [member]
Disclosure of detailed information about investment property [line items]
Undiscounted operating lease payments to be received	$ 3,241,525	$ 116,854	$ 664,259

Investment Properties - Investm

Investment Properties - Investment Properties Depreciated on a Straight-Line Basis Over Useful Lives (Detail)	12 Months Ended
	Dec. 31, 2021
Bottom of range [member] | Main plant buildings [Member]
Disclosure of detailed information about investment property [line items]
Investment properties are depreciated using the straight-line method over their estimated useful lives	10
Bottom of range [member] | Right-of-use assets [member]
Disclosure of detailed information about investment property [line items]
Investment properties are depreciated using the straight-line method over their estimated useful lives	10
Top of range [member] | Main plant buildings [Member]
Disclosure of detailed information about investment property [line items]
Investment properties are depreciated using the straight-line method over their estimated useful lives	40
Top of range [member] | Right-of-use assets [member]
Disclosure of detailed information about investment property [line items]
Investment properties are depreciated using the straight-line method over their estimated useful lives	50

Investment Properties - Summa_3

Investment Properties - Summary of Investment Properties, Fair Value (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of detailed information about investment property [line items]
Fair value	$ 22,144,787	$ 798,298	$ 12,538,083	$ 12,854,071
Fair value [member] | Level 3 of fair value hierarchy [member]
Disclosure of detailed information about investment property [line items]
Fair value	$ 36,158,216	$ 1,303,468	$ 19,799,714

Goodwill - Summary of Goodwill

Goodwill - Summary of Goodwill (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of reconciliation of changes in goodwill [line items]
Beginning balance	$ 52,709,053	$ 1,900,110	$ 50,198,436	$ 49,974,446
Acquisition through business combinations			2,567,842	264,977
Disposal of subsidiaries	(310,711)	(11,201)
Effect of foreign currency exchange differences	(325,929)	(11,749)	(57,225)	(40,987)
Ending balance	52,072,413	1,877,160	52,709,053	50,198,436
Cost [member]
Disclosure of reconciliation of changes in goodwill [line items]
Beginning balance	55,123,166	1,987,136	52,612,549	52,388,559
Acquisition through business combinations			2,567,842	264,977
Disposal of subsidiaries	(310,711)	(11,201)
Effect of foreign currency exchange differences	(325,929)	(11,749)	(57,225)	(40,987)
Ending balance	54,486,526	1,964,186	55,123,166	52,612,549
Accumulated impairment [Member]
Disclosure of reconciliation of changes in goodwill [line items]
Beginning balance	2,414,113	87,026	2,414,113	2,414,113
Ending balance	$ 2,414,113	$ 87,026	$ 2,414,113	$ 2,414,113

Goodwill - Summary of Carrying

Goodwill - Summary of Carrying Amounts of Goodwill Allocated to Cash-generating Units (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019TWD ($)	Dec. 31, 2018TWD ($)
Disclosure of information for cash-generating units [line items]
Goodwill	$ 52,072,413	$ 1,877,160	$ 52,709,053	$ 1,900,110	$ 50,198,436	$ 49,974,446
Packaging segment [member]
Disclosure of information for cash-generating units [line items]
Goodwill	35,412,424	1,276,583	35,703,625
Testing segment [member]
Disclosure of information for cash-generating units [line items]
Goodwill	13,304,040	479,598	13,365,068
EMS Segment Member [Member]
Disclosure of information for cash-generating units [line items]
Goodwill	3,207,848	115,640	3,492,259
All other segments [member]
Disclosure of information for cash-generating units [line items]
Goodwill	$ 148,101	$ 5,339	$ 148,101

Goodwill - Additional Informati

Goodwill - Additional Information (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disclosure of reconciliation of changes in goodwill [line items]
Impairment loss on goodwill	$ 0	$ 0	$ 0
Bottom of range [member]
Disclosure of reconciliation of changes in goodwill [line items]
Discount rate applied to cash flow projections	10.27%	10.39%	9.59%
Top of range [member]
Disclosure of reconciliation of changes in goodwill [line items]
Discount rate applied to cash flow projections	15.76%	14.71%	14.99%

Other Intangible Assets - Summa

Other Intangible Assets - Summary of Carrying Amounts of Each Class of Other Intangible Assets (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of detailed information about intangible assets [line items]
Beginning balance	$ 27,711,771
Additions	1,069,866	$ 38,568	$ 982,655	$ 1,350,908
Amortization expense	4,054,120	146,147	3,733,377	3,576,606
Ending balance	24,563,707	885,498	27,711,771
Cost [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	40,355,771	1,454,787	36,993,875	36,988,694
Additions	1,233,019	44,449	982,655	1,350,908
Disposals or derecognization	(324,321)	(11,692)	(70,007)	(2,045,396)
Disposal of subsidiaries	(801,642)	(28,899)	(38,125)
Acquisition through business combinations	622	23	2,567,342	752,548
Effect of foreign currency exchange differences	(258,383)	(9,315)	(79,969)	(52,879)
Ending balance	40,205,066	1,449,353	40,355,771	36,993,875
Accumulated depreciation and amortization [Member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	12,644,000	455,803	7,969,483	6,150,661
Amortization expense	4,054,120	146,147	3,733,377	3,576,606
Disposals or derecognization	(310,285)	(11,185)	(52,389)	(2,038,462)
Disposal of subsidiaries	(634,693)	(22,880)	(10,688)
Acquisition through business combinations	222	8	1,026,187	321,187
Effect of foreign currency exchange differences	(112,005)	(4,038)	(21,970)	(40,509)
Ending balance	15,641,359	563,855	12,644,000	7,969,483
Customer relationships [Member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	9,120,300
Ending balance	7,990,956	288,066	9,120,300
Customer relationships [Member] | Cost [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	11,890,283	428,633	11,000,001	11,915,636
Disposals or derecognization	(102,637)	(3,700)		(915,635)
Acquisition through business combinations			885,565
Effect of foreign currency exchange differences	(83,041)	(2,994)	4,717
Ending balance	11,704,605	421,939	11,890,283	11,000,001
Customer relationships [Member] | Accumulated depreciation and amortization [Member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	2,769,983	99,855	1,666,668	1,548,839
Amortization expense	1,049,759	37,843	1,000,000	1,033,464
Disposals or derecognization	(102,637)	(3,700)		(915,635)
Acquisition through business combinations			102,768
Effect of foreign currency exchange differences	(3,456)	(125)	547
Ending balance	3,713,649	133,873	2,769,983	1,666,668
Computer software [Member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	2,795,873
Ending balance	2,779,723	100,206	2,795,873
Computer software [Member] | Cost [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	6,966,449	251,134	4,606,878	4,401,045
Additions	1,193,060	43,009	951,439	1,358,533
Disposals or derecognization	(150,670)	(5,432)	(55,413)	(1,123,446)
Disposal of subsidiaries	(789,998)	(28,479)	(38,125)
Acquisition through business combinations	622	23	1,567,508	19,944
Effect of foreign currency exchange differences	(167,769)	(6,048)	(65,838)	(49,198)
Ending balance	7,051,694	254,207	6,966,449	4,606,878
Computer software [Member] | Accumulated depreciation and amortization [Member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	4,170,576	150,345	2,677,339	3,241,363
Amortization expense	971,190	35,010	729,330	583,300
Disposals or derecognization	(139,907)	(5,043)	(47,345)	(1,116,512)
Disposal of subsidiaries	(626,338)	(22,579)	(10,688)
Acquisition through business combinations	222	8	843,746	7,765
Effect of foreign currency exchange differences	(103,772)	(3,741)	(21,806)	(38,577)
Ending balance	4,271,971	154,000	4,170,576	2,677,339
Patents and acquired specific technology [Member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	15,720,213
Ending balance	13,730,404	494,968	15,720,213
Patents and acquired specific technology [Member] | Cost [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	21,319,179	768,536	21,318,696	20,588,356
Additions	2,000	72	171
Disposal of subsidiaries	(5,401)	(195)
Acquisition through business combinations				732,604
Effect of foreign currency exchange differences	(537)	(19)	312	(2,264)
Ending balance	21,315,241	768,394	21,319,179	21,318,696
Patents and acquired specific technology [Member] | Accumulated depreciation and amortization [Member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	5,598,966	201,837	3,600,173	1,332,687
Amortization expense	1,991,641	71,797	1,998,554	1,955,703
Disposal of subsidiaries	(5,288)	(191)
Acquisition through business combinations				313,422
Effect of foreign currency exchange differences	(482)	(17)	239	(1,639)
Ending balance	7,584,837	273,426	5,598,966	3,600,173
Others [Member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	75,385
Ending balance	62,624	2,258	75,385
Others [Member] | Cost [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	179,860	6,484	68,300	83,657
Additions	37,959	1,368	31,045	7,625
Disposals or derecognization	(71,014)	(2,560)	(14,594)	(6,315)
Disposal of subsidiaries	(6,243)	(225)
Acquisition through business combinations			114,269
Effect of foreign currency exchange differences	(7,036)	(254)	(19,160)	(1,417)
Ending balance	133,526	4,813	179,860	68,300
Others [Member] | Accumulated depreciation and amortization [Member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	104,475	3,766	25,303	27,772
Amortization expense	41,530	1,497	5,493	4,139
Disposals or derecognization	(67,741)	(2,442)	(5,044)	(6,315)
Disposal of subsidiaries	(3,067)	(110)
Acquisition through business combinations			79,673
Effect of foreign currency exchange differences	(4,295)	(155)	(950)	(293)
Ending balance	$ 70,902	$ 2,556	$ 104,475	$ 25,303

Other Intangible Assets - Sum_2

Other Intangible Assets - Summary of Other Intangible Assets Useful Lives (Detail)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Bottom of range [member] | Customer relationships [Member]
Disclosure of intangible assets with indefinite useful life [line items]
Other intangible assets useful lives	11	11
Bottom of range [member] | Computer software [Member]
Disclosure of intangible assets with indefinite useful life [line items]
Other intangible assets useful lives	2	2
Bottom of range [member] | Patents and acquired specific technology [Member]
Disclosure of intangible assets with indefinite useful life [line items]
Other intangible assets useful lives	5	5
Bottom of range [member] | Others [Member]
Disclosure of intangible assets with indefinite useful life [line items]
Other intangible assets useful lives	5	5
Top of range [member] | Customer relationships [Member]
Disclosure of intangible assets with indefinite useful life [line items]
Other intangible assets useful lives	16	16
Top of range [member] | Computer software [Member]
Disclosure of intangible assets with indefinite useful life [line items]
Other intangible assets useful lives	10	10
Top of range [member] | Patents and acquired specific technology [Member]
Disclosure of intangible assets with indefinite useful life [line items]
Other intangible assets useful lives	17	17
Top of range [member] | Others [Member]
Disclosure of intangible assets with indefinite useful life [line items]
Other intangible assets useful lives	10	32

Borrowings - Summary of Short T

Borrowings - Summary of Short Term Borrowings (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of detailed information about borrowings [line items]
Less: financial liabilities for hedging - current	$ (6,716,965)	$ (242,140)	$ (5,277,325)
Short-term borrowings	34,319,464	1,237,183	31,290,839
Short Term Bank Loans [Member]
Disclosure of detailed information about borrowings [line items]
Secured bank loans, annual interest rates both were 0.90%-1.87% as of December 31, 2020 and 2021	203,127	7,322	300,495
Unsecured bank loans, annual interest rates were 0.58%-3.38% and 0.40%-3.75% as of December 31, 2020 and 2021, respectively	40,833,302	1,472,001	34,297,362
Borrowings	41,036,429	1,479,323	34,597,857
Less: financial liabilities for hedging - current	6,716,965	242,140	3,307,018
Short-term borrowings	$ 34,319,464	$ 1,237,183	$ 31,290,839

Borrowings - Summary of Short_2

Borrowings - Summary of Short Term Borrowings (Parenthetical) (Detail)	Dec. 31, 2021	Dec. 31, 2020
Secured Loan [Member] | Bottom of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest rates	0.90%	0.90%
Secured Loan [Member] | Top of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest rates	1.87%	1.87%
Unsecured Loan [Member] | Bottom of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest rates	0.40%	0.58%
Unsecured Loan [Member] | Top of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest rates	3.75%	3.38%

Borrowings - Summary of Bank Lo

Borrowings - Summary of Bank Loans (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of detailed information about borrowings [line items]
Less: current portion	$ 4,526,683	$ 163,183	$ 2,250,121
Financial liabilities for hedging - current	6,716,965	242,140	5,277,325
Noncurrent portion	117,164,876	4,223,680	102,259,378
Bank loans [member]
Disclosure of detailed information about borrowings [line items]
Long-term borrowings	117,973,843	4,252,843	107,392,223
Less: current portion	4,526,683	163,183	2,250,121
Financial liabilities for hedging - current	0	0	1,970,307
Financial liabilities for hedging - non-current	4,780,931	172,348	5,910,919
Noncurrent portion	108,666,229	3,917,312	97,260,876
Bank loans [member] | Cost [member]
Disclosure of detailed information about borrowings [line items]
Long-term borrowings	117,977,485	4,252,974	107,496,546
Bank loans [member] | Cost [member] | Syndicated bank loans [Member]
Disclosure of detailed information about borrowings [line items]
Long-term borrowings	2,562,926	92,391	12,536,424
Bank loans [member] | Cost [member] | Other loans [Member]
Disclosure of detailed information about borrowings [line items]
Long-term borrowings	107,383,417	3,871,068	84,146,125
Bank loans [member] | Cost [member] | Mortgage loans [Member]
Disclosure of detailed information about borrowings [line items]
Long-term borrowings	8,031,142	289,515	10,813,997
Bank loans [member] | Net Unamortized Debt Issue Costs [member]
Disclosure of detailed information about borrowings [line items]
Long-term borrowings	$ 3,642	$ 131	$ 104,323

Borrowings - Summary of Bank _2

Borrowings - Summary of Bank Loans (Parenthetical) (Detail)	Dec. 31, 2021	Dec. 31, 2020
Syndicated bank loans [Member] | Bottom of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest rates	1.08%	1.15%
Syndicated bank loans [Member] | Top of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest rates	1.08%	1.17%
Other loans [Member] | Bottom of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest rates	0.40%	0.56%
Other loans [Member] | Top of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest rates	4.00%	4.15%
Mortgage loans [Member] | Bottom of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest rates	2.32%	1.90%
Mortgage loans [Member] | Top of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest rates	4.55%	4.90%

Borrowings - Summary of Bills P

Borrowings - Summary of Bills Payable (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of detailed information about borrowings [line items]
Long-term bills payable	$ 8,498,647	$ 306,368	$ 4,998,502
Unamortized Discounts [member]
Disclosure of detailed information about borrowings [line items]
Long-term bills payable	1,353	49	1,498
Longterm Bills Payable [member]
Disclosure of detailed information about borrowings [line items]
Long-term bills payable	8,500,000	306,417	5,000,000
Ta Ching Bills Finance Corporation [member]
Disclosure of detailed information about borrowings [line items]
Long-term bills payable	2,500,000	90,123	1,000,000
Mega Bills Finance Corporation [Member]
Disclosure of detailed information about borrowings [line items]
Long-term bills payable	2,000,000	72,098	2,000,000
China Bills Finance Corporation [member]
Disclosure of detailed information about borrowings [line items]
Long-term bills payable	2,500,000	90,123	$ 2,000,000
International Bills Finance Corporation [member]
Disclosure of detailed information about borrowings [line items]
Long-term bills payable	$ 1,500,000	$ 54,073

Borrowings - Summary of Bills_2

Borrowings - Summary of Bills Payable (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Ta Ching Bills Finance Corporation [member]
Disclosure of detailed information about borrowings [line items]
Annual interest rates	0.65%	0.91%
Borrowings maturity	January 2023 to March 2023
Mega Bills Finance Corporation [Member]
Disclosure of detailed information about borrowings [line items]
Borrowings maturity	March 2023
Mega Bills Finance Corporation [Member] | Bottom of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest rates	0.65%	0.92%
Mega Bills Finance Corporation [Member] | Top of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest rates	0.65%	0.93%
China Bills Finance Corporation [member]
Disclosure of detailed information about borrowings [line items]
Borrowings maturity	March 2023 to December 2023
China Bills Finance Corporation [member] | Bottom of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest rates	0.65%	0.65%
China Bills Finance Corporation [member] | Top of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest rates	0.65%	0.90%
International Bills Finance Corporation [member]
Disclosure of detailed information about borrowings [line items]
Annual interest rates	0.65%
Borrowings maturity	March 2023

Bonds Payable - Summary of Bond

Bonds Payable - Summary of Bonds Payable (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of detailed information about borrowings [line items]
Bonds payable	$ 52,267,337	$ 1,884,187	$ 56,253,554
Noncurrent portion	42,364,627	1,527,204	49,253,603
Less: current portion of bonds payable	9,902,710	356,983	6,999,951
Cost [member]
Disclosure of detailed information about borrowings [line items]
Bonds payable	52,692,581	1,899,517	56,307,200
Cost [member] | Repayable at maturity in January 2021 [member]
Disclosure of detailed information about borrowings [line items]
Bonds payable	0	0	7,000,000
Cost [member] | Repayable at maturity in January 2023 [member]
Disclosure of detailed information about borrowings [line items]
Bonds payable	2,000,000	72,098	2,000,000
Cost [member] | Repayable at maturity in January 2022 [member]
Disclosure of detailed information about borrowings [line items]
Bonds payable	3,700,000	133,381	3,700,000
Cost [member] | Repayable at maturity in January 2024 [member]
Disclosure of detailed information about borrowings [line items]
Bonds payable	4,300,000	155,011	4,300,000
Cost [member] | Repayable at maturity in April 2024 [Member]
Disclosure of detailed information about borrowings [line items]
Bonds payable	6,500,000	234,319	6,500,000
Cost [member] | Repayable at maturity in April 2026 [Member]
Disclosure of detailed information about borrowings [line items]
Bonds payable	3,500,000	126,172	3,500,000
Cost [member] | Repayable at maturity in April 2025 [Member]
Disclosure of detailed information about borrowings [line items]
Bonds payable	10,000,000	360,490	10,000,000
Cost [member] | Repayable at maturity in October 2022 [Member]
Disclosure of detailed information about borrowings [line items]
Bonds payable	6,204,800	223,677	6,204,800
Cost [member] | Repayable at maturity in October 2024 [Member]
Disclosure of detailed information about borrowings [line items]
Bonds payable	3,102,400	111,839	3,102,400
Cost [member] | Repayable at maturity in August 2023 [Member]
Disclosure of detailed information about borrowings [line items]
Bonds payable	3,000,000	108,147	3,000,000
Cost [member] | Repayable at maturity in August 2025 [Member]
Disclosure of detailed information about borrowings [line items]
Bonds payable	5,000,000	180,245	5,000,000
Cost [member] | Repayable at maturity in August 2027 [Member]
Disclosure of detailed information about borrowings [line items]
Bonds payable	2,000,000	72,098	2,000,000
Cost [member] | Repayable at Maturity in March 2027 [Member]
Disclosure of detailed information about borrowings [line items]
Bonds payable	3,385,381	122,040
Discounts on bonds payable [member]
Disclosure of detailed information about borrowings [line items]
Bonds payable	$ 425,244	$ 15,330	$ 53,646

Bonds Payable - Summary of Bo_2

Bonds Payable - Summary of Bonds Payable (Parenthetical) (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020USD ($)
Repayable at maturity in January 2021 [member]
Disclosure of detailed information about borrowings [line items]
Interest rate	1.30%	1.30%	1.30%
Repayable at maturity in January 2023 [member]
Disclosure of detailed information about borrowings [line items]
Interest rate	1.50%	1.50%	1.50%
Repayable at maturity in January 2022 [member]
Disclosure of detailed information about borrowings [line items]
Interest rate	1.25%	1.25%	1.25%
Repayable at maturity in January 2024 [member]
Disclosure of detailed information about borrowings [line items]
Interest rate	1.45%	1.45%	1.45%
Repayable at maturity in April 2024 [Member]
Disclosure of detailed information about borrowings [line items]
Interest rate	0.90%	0.90%	0.90%
Repayable at maturity in April 2026 [Member]
Disclosure of detailed information about borrowings [line items]
Interest rate	1.03%	1.03%	1.03%
Repayable at maturity in October 2022 [Member]
Disclosure of detailed information about borrowings [line items]
Interest rate	2.15%	2.15%	2.15%
Notional Amount		$ 200,000	$ 200,000
Repayable at maturity in October 2024 [Member]
Disclosure of detailed information about borrowings [line items]
Interest rate	2.50%	2.50%	2.50%
Notional Amount		$ 100,000	$ 100,000
Repayable at maturity in April 2025 [Member]
Disclosure of detailed information about borrowings [line items]
Interest rate	0.90%	0.90%	0.90%
Repayable at maturity in August 2023 [Member]
Disclosure of detailed information about borrowings [line items]
Interest rate	0.72%	0.72%	0.72%
Repayable at maturity in August 2025 [Member]
Disclosure of detailed information about borrowings [line items]
Interest rate	0.85%	0.85%	0.85%
Repayable at maturity in August 2027 [Member]
Disclosure of detailed information about borrowings [line items]
Interest rate	0.95%	0.95%	0.95%
Repayable at Maturity in March 2027 [Member]
Disclosure of detailed information about borrowings [line items]
Notional Amount	$ 779,801
Repayable at Maturity in March 2027 [Member] | Interest Rate Period One [Member]
Disclosure of detailed information about borrowings [line items]
Interest rate	0.10%	0.10%
Repayable at Maturity in March 2027 [Member] | Interest Rate Period Two [Member]
Disclosure of detailed information about borrowings [line items]
Interest rate	0.20%	0.20%
Repayable at Maturity in March 2027 [Member] | Interest Rate Period Three [Member]
Disclosure of detailed information about borrowings [line items]
Interest rate	0.60%	0.60%
Repayable at Maturity in March 2027 [Member] | Interest Rate Period Four [Member]
Disclosure of detailed information about borrowings [line items]
Interest rate	1.30%	1.30%
Repayable at Maturity in March 2027 [Member] | Interest Rate Period Five [Member]
Disclosure of detailed information about borrowings [line items]
Interest rate	1.80%	1.80%
Repayable at Maturity in March 2027 [Member] | Interest Rate Period Six [Member]
Disclosure of detailed information about borrowings [line items]
Interest rate	2.00%	2.00%

Bonds Payable - Additional Info

Bonds Payable - Additional Information (Detail) ¥ / shares in Units, $ / shares in Units, ¥ in Thousands, $ in Thousands, $ in Thousands	1 Months Ended			12 Months Ended
	Mar. 31, 2021CNY (¥)¥ / shares	Sep. 30, 2020$ / shares	Dec. 31, 2017TWD ($)$ / shares	Dec. 31, 2021TWD ($)¥ / shares	Dec. 31, 2021USD ($)	Dec. 31, 2021CNY (¥)
Unsecured Domestic Convertible Bonds [Member]
Disclosure of detailed information about borrowings [line items]
Bonds maturity period			3 years
Secured domestic bonds conversion price | $ / shares		$ 4.8
Percentage of current conversion price on Stock Exchange		30.00%
Number of consecutive trading days for determining Conversion price		30 days
Secured Domestic Convertible Bonds [Member]
Disclosure of detailed information about borrowings [line items]
Secured domestic bonds conversion price | $ / shares			$ 4.8
Notional Amount | $			$ 250,000
USISH Bonds [Member]
Disclosure of detailed information about borrowings [line items]
Notional Amount				$ 404,026	$ 14,565
Effective interest rate on Contract				4.2989%	4.2989%	4.2989%
Aggregate fair value of the redemption option				$ 6,756	$ 244
USISH Bonds [Member] | USISH [Member]
Disclosure of detailed information about borrowings [line items]
Borrowings maturity	Within 5 trading days after maturity
Borrowings, interest rate	108.00%
Borrowings	¥ 3,450,000
Notional Amount	¥ 100
Conversion Period of Bonds	9 months
Conversion Price | ¥ / shares	¥ 20.25			$ 19.75
Percentage of current conversion price on Stock Exchange				80.00%	80.00%	80.00%
Percentage of par value on USISH Bonds				102.00%	102.00%	102.00%
USISH Bonds [Member] | USISH [Member] | Bottom of range [member]
Disclosure of detailed information about borrowings [line items]
Percentage of current conversion price on Stock Exchange				70.00%	70.00%	70.00%
Number of consecutive trading days for determining Conversion price				15 days
USISH Bonds [Member] | USISH [Member] | Top of range [member]
Disclosure of detailed information about borrowings [line items]
Number of consecutive trading days for determining Conversion price				30 days
USISH Bonds [Member] | USIE and ASE (Shanghai) Inc [Member]
Disclosure of detailed information about borrowings [line items]
Borrowings	¥ 2,670,199
Unconverted USISH Bonds [Member] | USISH [Member]
Disclosure of detailed information about borrowings [line items]
Borrowings						¥ 30,000
Percentage of current conversion price on Stock Exchange				130.00%	130.00%	130.00%
Unconverted USISH Bonds [Member] | USISH [Member] | Bottom of range [member]
Disclosure of detailed information about borrowings [line items]
Number of consecutive trading days for determining Conversion price				20 days
Unconverted USISH Bonds [Member] | USISH [Member] | Top of range [member]
Disclosure of detailed information about borrowings [line items]
Percentage of current conversion price on Stock Exchange				130.00%	130.00%	130.00%
Number of consecutive trading days for determining Conversion price				30 days

Other Payables - Summary of Oth

Other Payables - Summary of Other Payables (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Subclassifications of assets, liabilities and equities [abstract]
Accrued salary and bonus	$ 12,217,011	$ 440,411	$ 12,448,548
Payables for property, plant and equipment	13,607,664	490,543	10,013,971
Accrued employees' compensation and remuneration to directors	7,711,445	277,990	4,405,981
Accrued employee insurance	1,204,387	43,417	1,105,122
Accrued utilities	581,662	20,968	536,491
Others	11,374,731	410,049	10,905,510
Other payables	$ 46,696,900	$ 1,683,378	$ 39,415,623

Retirement Benefit Plans - Addi

Retirement Benefit Plans - Additional Information (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2022TWD ($)	Dec. 31, 2022USD ($)	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)	Dec. 31, 2021USD ($)
Disclosure of defined benefit plans [line items]
Percentage of monthly pension contributions			6.00%	6.00%
Pension costs			$ 214,599	$ 7,736	$ 217,186	$ 277,041
Expected contribution to defined benefit plans	$ 595,871	$ 21,481	513,781
Defined benefit obligation, pension payments			26,144	942
Pension plans for executive managers [member]
Disclosure of defined benefit plans [line items]
Pension costs			32,836	$ 1,183	11,184	$ 11,567
Accrued pension liabilities			$ 369,999		$ 346,015		$ 13,338
Bottom of range [member]
Disclosure of defined benefit plans [line items]
Average duration of the defined benefit obligation			9 years	9 years	9 years
Top of range [member]
Disclosure of defined benefit plans [line items]
Average duration of the defined benefit obligation			16 years	16 years	16 years

Retirement Benefit Plans - Summ

Retirement Benefit Plans - Summary of Defined Benefit Plans Amounts Included in Consolidated Balance Sheets (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019TWD ($)	Dec. 31, 2018TWD ($)
Disclosure of net defined benefit liability (asset) [abstract]
Present value of the defined benefit obligation	$ 11,424,860	$ 411,855	$ 12,159,145
Fair value of the plan assets	(5,863,264)	(211,365)	(5,962,305)
Present value of unfunded defined benefit obligation	5,561,596	200,490	6,196,840	$ 223,390	$ 4,926,396	$ 4,805,016
Recorded under other payables	(67,524)	(2,434)	(102,367)
Recorded under other non-current assets			26,306
Net defined benefit liability	$ 5,494,072	$ 198,056	$ 6,120,779

Retirement Benefit Plans - Su_2

Retirement Benefit Plans - Summary of Movements in Net Defined Benefit Liability (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of net defined benefit liability (asset) [line items]
Beginning balance	$ 6,196,840	$ 223,390	$ 4,926,396	$ 4,805,016
Current service cost	173,307	6,248	193,693	211,226
Past service cost and gain on settlements	(10,284)	(371)	(25,891)
Net interest expense (income)	18,740	676	38,200	54,248
Recognized in profit or loss	181,763	6,553	206,002	265,474
Return on plan assets (excluding amounts included in net interest)	(42,636)	(1,537)	(109,616)	(104,516)
Changes in financial assumptions	(418,542)	(15,088)	465,433	398,732
Experience adjustments	242,896	8,756	281,661	70,374
Changes in demographic assumptions	160,156	5,773	(36,627)	(2,329)
Recognized in other comprehensive income	(58,126)	(2,096)	600,851	362,261
Contributions from the employer	(542,584)	(19,560)	(620,433)	(514,617)
Benefits paid from the pension fund	6,023	217	50,707	0
Benefits paid from the Group	(80,603)	(2,906)	(14,520)	(21,439)
Assets extinguished on settlement			11,910
Business combinations	46,291	1,669	1,018,480	34,477
Exchange differences on foreign plans	(188,008)	(6,777)	17,447	(4,776)
Ending balance	5,561,596	200,490	6,196,840	4,926,396
Defined benefit obligation [member]
Disclosure of net defined benefit liability (asset) [line items]
Beginning balance	12,159,145	438,325	10,668,574	10,297,139
Current service cost	173,307	6,248	193,693	211,226
Past service cost and gain on settlements	(10,284)	(371)	(25,891)
Net interest expense (income)	78,501	2,830	119,314	151,635
Recognized in profit or loss	241,524	8,707	287,116	362,861
Return on plan assets (excluding amounts included in net interest)	0	0	0	0
Changes in financial assumptions	(418,542)	(15,088)	465,433	398,732
Experience adjustments	242,896	8,756	281,661	70,374
Changes in demographic assumptions	160,156	5,773	(36,627)	(2,329)
Recognized in other comprehensive income	(15,490)	(559)	710,467	466,777
Contributions from the employer	0	0	0	0
Benefits paid from the pension fund	(556,419)	(20,058)	(552,430)	(393,897)
Benefits paid from the Group	(80,603)	(2,906)	(14,520)	(21,439)
Assets extinguished on settlement			0
Business combinations	46,291	1,669	1,018,480	62,857
Exchange differences on foreign plans	(369,588)	(13,323)	41,458	(105,724)
Ending balance	11,424,860	411,855	12,159,145	10,668,574
Fair value of plan assets [member]
Disclosure of net defined benefit liability (asset) [line items]
Beginning balance	(5,962,305)	(214,935)	(5,742,178)	(5,492,123)
Current service cost	0	0	0	0
Past service cost and gain on settlements	0		0
Net interest expense (income)	(59,761)	(2,154)	(81,114)	(97,387)
Recognized in profit or loss	(59,761)	(2,154)	(81,114)	(97,387)
Return on plan assets (excluding amounts included in net interest)	(42,636)	(1,537)	(109,616)	(104,516)
Changes in financial assumptions	0	0	0	0
Experience adjustments	0	0	0	0
Changes in demographic assumptions	0	0	0	0
Recognized in other comprehensive income	(42,636)	(1,537)	(109,616)	(104,516)
Contributions from the employer	(542,584)	(19,560)	(620,433)	(514,617)
Benefits paid from the pension fund	562,442	20,275	603,137	393,897
Benefits paid from the Group	0	0	0	0
Assets extinguished on settlement			11,910
Business combinations	0	0	0	(28,380)
Exchange differences on foreign plans	181,580	6,546	(24,011)	100,948
Ending balance	$ (5,863,264)	$ (211,365)	$ (5,962,305)	$ (5,742,178)

Retirement Benefit Plans - Su_3

Retirement Benefit Plans - Summary of Fair Value of the Plan Assets by Major Categories (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of fair value of plan assets [abstract]
Cash	$ 2,267,223	$ 81,731	$ 2,236,340
Equity instruments	2,334,180	84,145	2,459,708
Debt instruments	1,039,412	37,470	1,092,115
Others	222,449	8,019	174,142
Total	$ 5,863,264	$ 211,365	$ 5,962,305

Retirement Benefit Plans - Su_4

Retirement Benefit Plans - Summary of Key Assumptions Used for the Actuarial Valuations (Detail)	Dec. 31, 2021	Dec. 31, 2020
Bottom of range [member]
Disclosure of defined benefit plans [line items]
Discount rates	0.05%	0.00%
Expected rates of salary increase	1.00%	1.00%
Top of range [member]
Disclosure of defined benefit plans [line items]
Discount rates	3.31%	2.77%
Expected rates of salary increase	4.02%	4.06%

Retirement Benefit Plans - Su_5

Retirement Benefit Plans - Summary of Sensitivity Analysis on Defined Obligations (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Actuarial assumption of discount rates [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Change in defined obligation due to increase in actuarial assumption	$ (548,265)	$ (19,764)	$ (617,803)
Change in defined obligation due to decrease in actuarial assumption	593,980	21,412	600,451
Actuarial assumption of expected rates of salary increases [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Change in defined obligation due to increase in actuarial assumption	538,689	19,419	611,217
Change in defined obligation due to decrease in actuarial assumption	$ (503,700)	$ (18,158)	$ (565,555)

Retirement Benefit Plans - Su_6

Retirement Benefit Plans - Summary of Maturity Analysis of Undiscounted Pension Benefit (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of defined benefit plans [line items]
Maturity analysis of undiscounted pension benefit	$ 15,755,564	$ 567,973	$ 15,377,190
Less than 1 year [member]
Disclosure of defined benefit plans [line items]
Maturity analysis of undiscounted pension benefit	561,812	20,253	498,092
1-5 years [member]
Disclosure of defined benefit plans [line items]
Maturity analysis of undiscounted pension benefit	2,593,560	93,495	2,553,522
More than 5 years [member]
Disclosure of defined benefit plans [line items]
Maturity analysis of undiscounted pension benefit	$ 12,600,192	$ 454,225	$ 12,325,576

Equity - Summary of Share Capit

Equity - Summary of Share Capital (Detail) shares in Thousands, $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)shares	Dec. 31, 2021USD ($)shares	Dec. 31, 2020TWD ($)shares
Disclosure of classes of share capital [abstract]
Numbers of shares authorized (in thousands)	5,500,000	5,500,000	5,500,000
Numbers of shares reserved (in thousands) Employee share options	400,000	400,000	400,000
Number of shares issued and fully paid (in thousands)	4,408,650	4,408,650	4,351,592
Share capital authorized	$ 55,000,000	$ 1,982,696	$ 55,000,000
Share capital reserved Employee share options	$ 4,000,000	$ 144,196	$ 4,000,000

Equity - Additional Information

Equity - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2021shares$ / shares	Dec. 31, 2021shares$ / shares$ / shares	Dec. 31, 2021$ / sharesshares	Nov. 08, 2021$ / sharesshares	Nov. 08, 2021$ / sharesshares	Dec. 31, 2020shares
Disclosure of classes of share capital [line items]
Number of shares represented by each ADS	2	2
Percentage of legal reserve on share capital	25.00%	25.00%
American depository shares (ADs) [member]
Disclosure of classes of share capital [line items]
Number of shares represented by each ADS	2	2
Number of shares outstanding	157,164,000	157,164,000	157,164,000			107,964,000
Ordinary shares [member]
Disclosure of classes of share capital [line items]
Number of shares outstanding	314,328,000	314,328,000	314,328,000			215,927,000
Ordinary shares [member] | Board of Directors [Member]
Disclosure of classes of share capital [line items]
Number of ordinary shares issued	55,000,000	55,000,000	55,000,000	55,000,000	55,000,000
Top of range [member]
Disclosure of classes of share capital [line items]
Percentage of cash dividend on dividend distribution	30.00%	30.00%
Top of range [member] | Ordinary shares [member]
Disclosure of classes of share capital [line items]
Number of ordinary shares issued	53,067,000	53,067,000	53,067,000
Weighted average share price | (per share)	$ 104.2	$ 3.8
Top of range [member] | Ordinary shares [member] | Board of Directors [Member]
Disclosure of classes of share capital [line items]
Par value per share | (per share)				$ 150	$ 5
Bottom of range [member] | Ordinary shares [member]
Disclosure of classes of share capital [line items]
Number of ordinary shares issued	1,933,000	1,933,000	1,933,000
Weighted average share price | (per share)	$ 106.4	$ 3.8
Bottom of range [member] | Ordinary shares [member] | Board of Directors [Member]
Disclosure of classes of share capital [line items]
Par value per share | (per share)	$ 90	$ 90	$ 3	$ 90	$ 3

Equity - Summary of Capital Sur

Equity - Summary of Capital Surplus (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of classes of share capital [abstract]
Issuance of ordinary shares	$ 16,049,286	$ 578,561	$ 13,548,426
Merger by share exchange	117,693,658	4,242,742	117,693,658
Difference between consideration and the carrying amount of the subsidiaries' net assets during actual disposal or acquisition	3,240,987	116,835	3,240,987
Exercised employee share options	2,362,951	85,182	1,617,254
Treasury share transactions	816,186	29,422	510,449
Expired share options (Note 28)	645,903	23,284	645,903
Capital surplus deficit distributed as cash dividends	140,808,971	5,076,026	137,256,677
Changes in percentage of ownership interest in subsidiaries	1,451	52	1,451
Share of changes in capital surplus of associates	10,706	386	41,239
Dividends that the claim period has elapsed and unclaimed by shareholders	5,183	187	3,550
Capital surplus offset deficit	17,340	625	46,240
Employee share options	1,442,132	51,988	1,894,952
Employee restricted stock awards	1,193,782	43,034	0
Others	230,943	8,326	569,681
Capital surplus for other purpose	2,866,857	103,348	2,464,633
Capital surplus	$ 143,693,168	$ 5,179,999	$ 139,767,550

Equity - Schedule of appropria

Equity - Schedule of appropriation of retained earnings (Detail) - TWD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Appropriation of earnings	$ 19,510,000	$ 14,310,735
Dividends per share	$ 4.2	$ 2
Legal reserve [member]
Appropriation of earnings	$ 2,398,814	$ 1,697,489
Special reserve [member]
Appropriation of earnings	(1,278,670)	3,944,915
Cash dividends [member]
Appropriation of earnings	$ 18,389,856	$ 8,668,331

Equity - Summary of Exchange Di

Equity - Summary of Exchange Differences on Translating Foreign Operations (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Balance at January 1	$ 231,737,116		$ 212,802,312
Exchange differences arising on translating foreign operations	(4,094,565)	$ (147,605)	(831,784)	$ (5,202,145)
Share from associates and joint venture accounted for using the equity method	29,209	1,053	131,009	(85,975)
Balance at December 31	268,171,060	9,667,306	231,737,116	212,802,312
Exchange differences on translating foreign operations [member]
Balance at January 1	(11,641,939)	(419,681)	(10,762,684)	(5,888,574)
Exchange differences arising on translating foreign operations	(3,203,730)	(115,491)	(1,173,204)	(4,788,135)
Share from associates and joint venture accounted for using the equity method	21,307	768	101,038	(85,975)
Disposal of associates and joint venture accounted for using the equity method			29,971
Disposal of foreign operations	(569,284)	(20,522)	162,940
Balance at December 31	$ (15,393,646)	$ (554,926)	$ (11,641,939)	$ (10,762,684)

Equity - Summary of Unrealized

Equity - Summary of Unrealized Gain (Loss) on Financial Assets at FVTOCI (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Financial assets at fair value through other comprehensive income [line items]
Balance at January 1	$ 1,741,134
Ending balance	2,019,812	$ 72,812	$ 1,741,134
Unrealized gain (loss) on financial assets at fair value through other comprehensive income [member]
Financial assets at fair value through other comprehensive income [line items]
Balance at January 1	2,027,902	73,104	(203,098)	$ (1,015,107)
Debt instruments	63,722	2,297	(2,136)	(2,052)
Equity instruments	(8,671)	(313)	(405,020)	(283,472)
Share from associates and joint venture accounted for using the equity method	3,599,703	129,766	2,655,570	1,501,689
Disposal of associates and joint venture accounted for using the equity method			1,094
Cumulative unrealized loss of equity instruments transferred to retained earnings due to disposal	33,258	1,199	16,383
Cumulative unrealized loss transferred to retained earnings due to disposal of equity instruments in relation to associates and joint venture accounted for using the equity method	(1,525,553)	(54,995)	(34,891)	(404,156)
Ending balance	$ 4,190,361	$ 151,058	$ 2,027,902	$ (203,098)

Equity - Summary of Unearned Em

Equity - Summary of Unearned Employee Compensation (Detail) - 12 months ended Dec. 31, 2021 $ in Thousands, $ in Thousands	TWD ($)	USD ($)
Disclosure of Restricted Stock Awards for Employees [Abstract]
Balance at January 1	$ 0	$ 0
Issuance of employee restricted stock awards	(1,343,782)	(48,442)
Share-based payment expenses	178,791	6,446
Balance at December 31	$ (1,164,991)	$ (41,996)

Equity - Summary of Treasury Sh

Equity - Summary of Treasury Shares (Detail) shares in Thousands	12 Months Ended
	Dec. 31, 2021shares
Beginning balance	72,941
Addition	53,067
Ending balance	126,008
Shares repurchased for cancellation [member]
Beginning balance	0
Addition	53,067
Ending balance	53,067
Shares held by subsidiaries [member]
Beginning balance	72,941
Addition	0
Ending balance	72,941

Equity - Schedule Of Detailed I

Equity - Schedule Of Detailed Information About Hedges Of Net Investments Of Foreign Operations (Details) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of detailed information about hedges [line items]
Balance at January 1	$ (429,265)	$ (15,475)	$ 0
Foreign currency risk – loans denominated in foreign currency	551,098	19,867	(429,265)
Balance at December 31	$ 121,833	$ 4,392	$ (429,265)

Equity - Summary of Shares Held

Equity - Summary of Shares Held By Subsidiaries (Detail) shares in Thousands, $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)shares	Dec. 31, 2021USD ($)shares	Dec. 31, 2020TWD ($)shares
Disclosure of subsidiaries [Line Items]
Shares Held By Subsidiaries (in thousands)	72,941	72,941	72,941
Shares Held By Subsidiaries, Value	$ 1,959,107	$ 70,624	$ 1,959,107
ASE Test Limited [member]
Disclosure of subsidiaries [Line Items]
Shares Held By Subsidiaries (in thousands)	44,100	44,100	44,100
Shares Held By Subsidiaries, Value	$ 1,380,721	$ 49,774	$ 1,380,721
J & R Holding Limited [member]
Disclosure of subsidiaries [Line Items]
Shares Held By Subsidiaries (in thousands)	23,352	23,352	23,352
Shares Held By Subsidiaries, Value	$ 381,709	$ 13,760	$ 381,709
ASE Test, Inc. [member]
Disclosure of subsidiaries [Line Items]
Shares Held By Subsidiaries (in thousands)	5,489	5,489	5,489
Shares Held By Subsidiaries, Value	$ 196,677	$ 7,090	$ 196,677
Fair value [member]
Disclosure of subsidiaries [Line Items]
Shares Held By Subsidiaries, Value	7,768,270	280,039	5,930,144
Fair value [member] | ASE Test Limited [member]
Disclosure of subsidiaries [Line Items]
Shares Held By Subsidiaries, Value	4,696,675	169,311	3,585,349
Fair value [member] | J & R Holding Limited [member]
Disclosure of subsidiaries [Line Items]
Shares Held By Subsidiaries, Value	2,486,975	89,653	1,898,508
Fair value [member] | ASE Test, Inc. [member]
Disclosure of subsidiaries [Line Items]
Shares Held By Subsidiaries, Value	$ 584,620	$ 21,075	$ 446,287

Equity - Summary of Non-control

Equity - Summary of Non-controlling Interests (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Balance at January 1	$ 231,737,116		$ 212,802,312
Share of profit for the year	2,099,830	$ 75,697	1,681,320	$ 1,207,974
Other comprehensive income (loss) for the year
Exchange difference on translating foreign operations	(4,094,565)	(147,605)	(831,784)	(5,202,145)
Share of other comprehensive income from associates accounted for using the equity method	29,209	1,053	131,009	(85,975)
Balance at December 31	268,171,060	9,667,306	231,737,116	212,802,312
Non-controlling interests [member]
Balance at January 1	15,622,009	563,158	13,374,912	17,639,487
Share of profit for the year	2,099,830	75,697	1,681,320	1,207,974
Other comprehensive income (loss) for the year
Exchange difference on translating foreign operations	(321,551)	(11,592)	178,480	(414,010)
Unrealized gain (loss) on equity instruments at FVTOCI	50,679	1,827	1,321	(10,773)
Gain (Loss) from hedging	187,502	6,759	(145,559)
Remeasurement on defined benefit plans	1,497	54	(9,075)	(7,422)
Share of other comprehensive income from associates accounted for using the equity method	7,902	285
Non-controlling interests arising from acquisition or disposal of subsidiaries (Note 29)			298	666,651
Acquisition of non-controlling interests in subsidiaries (Note 31)			(116,738)	(5,084,785)
Issuance of ordinary shares by subsidiaries (Note 29)			1,711,453	83,044
Subsidiaries' buy back of their own outstanding ordinary shares (Note 31)	(2,748,521)	(99,081)	(2,299,533)	(2,017,319)
Equity component of convertible bonds issued by subsidiaries	393,199	14,174
Non-controlling interest relating to outstanding vested employee share options granted by subsidiaries	314,398	11,334	1,591,904	1,672,310
Cash dividends distributed to non-controlling interests	(1,062,529)	(38,303)	(346,774)	(360,245)
Balance at December 31	$ 14,544,415	$ 524,312	$ 15,622,009	$ 13,374,912

Profit Before Income Tax - Summ

Profit Before Income Tax - Summary of Other Operating Income and Expenses, Net (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Analysis of income and expense [abstract]
Rental income	$ 175,373	$ 6,322	$ 153,682	$ 136,301
Gains (loss) on disposal of property, plant and equipment and other assets	71,770	2,587	460,868	(164,467)
Impairment loss (Note 15)	(126,766)	(4,571)	(992,273)	(201,006)
Royalty income	135,400	4,881
Others	934,052	33,673	880,215	(39,383)
Other operating income and expenses, net	$ 1,189,829	$ 42,892	$ 502,492	$ (268,555)

Profit Before Income Tax - Su_2

Profit Before Income Tax - Summary of Other Income (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Analysis of income and expense [abstract]
Bank deposits	$ 529,132	$ 19,074	$ 520,783	$ 549,681
Contracts with customers	13,197	476
Government subsidies	767,918	27,683	803,049	624,351
Dividends income	289,852	10,449	150,715	185,061
Other income	$ 1,600,099	$ 57,682	$ 1,474,547	$ 1,359,093

Profit Before Income Tax - Su_3

Profit Before Income Tax - Summary of Other Gains and Losses (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Analysis of income and expense [abstract]
Remeasurement gain on investments accounted for using the equity method due to step acquisition				$ 319,712
Net gain on financial assets mandatorily at FVTPL	$ 1,199,065	$ 43,225	$ 3,211,125	3,631,763
Net loss arising on financial instruments held for trading	(2,689,070)	(96,938)	(3,282,973)	(1,984,941)
Gain on disposal of subsidiaries (Note 30)	17,340,418	625,105	802,753
Foreign exchange gain, net	1,395,054	50,290	1,005,374	1,125,681
Gain recognized in bargain purchase transaction (Note 29)	33,114	1,194		0
Gain (loss) on disposal of investments accounted for using the equity method	(67,482)	(2,433)	91,297
Impairment loss on financial assets				(400,201)
Others				(8,025)
Other gains and losses	$ 17,211,099	$ 620,443	$ 1,827,576	$ 2,683,989

Profit Before Income Tax - Su_4

Profit Before Income Tax - Summary of Finance Costs (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Analysis of income and expense [abstract]
Interest on lease liabilities	$ 105,159	$ 3,791	$ 88,026	$ 88,742
Interest on borrowings and bonds payable	2,790,368	100,590	3,498,999	4,211,541
Total interest expense for financial liabilities measured at amortized cost	2,895,527	104,381	3,587,025	4,300,283
Less: Amounts included in the cost of qualifying assets
Inventories related to real estate business	(71,011)	(2,560)	(95,589)	(35,713)
Property, plant and equipment	(25,581)	(922)	(54,208)	(77,715)
Interest expense	2,798,935	100,899	3,437,228	4,186,855
Other finance costs	32,372	1,167	22,283	16,540
Finance costs	$ 2,831,307	$ 102,066	$ 3,459,511	$ 4,203,395

Profit Before Income Tax - Su_5

Profit Before Income Tax - Summary of Capitalized Borrowing Costs (Detail)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Inventories related to real estate business [member] | Bottom of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest capitalization rates	4.20%	4.20%	4.35%
Inventories related to real estate business [member] | Top of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest capitalization rates	4.35%	4.75%	4.85%
Property, plant and equipment [member] | Bottom of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest capitalization rates	0.48%	0.49%	0.96%
Property, plant and equipment [member] | Top of range [member]
Disclosure of detailed information about borrowings [line items]
Annual interest capitalization rates	1.08%	3.47%	4.03%

Profit Before Income Tax - Su_6

Profit Before Income Tax - Summary of Depreciation and Amortization (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Analysis of income and expense [Line Items]
Property, plant and equipment depreciation	$ 48,604,160	$ 1,752,133	$ 46,016,548	$ 45,240,667
Right-of-use assets	1,114,950	40,193	946,880	1,055,458
Investment properties	751,047	27,074	562,260	594,110
Intangible assets amortization	4,054,120	146,147	3,733,377	3,576,606
Depreciation and amortization	54,524,277	1,965,547	51,259,065	50,466,841
Depreciation expense	50,470,157	1,819,400	47,525,688	46,890,235
Operating costs [member]
Analysis of income and expense [Line Items]
Intangible assets amortization	2,443,870	88,099	2,231,060	2,092,074
Depreciation expense	46,880,267	1,689,988	44,017,839	43,749,333
Operating expenses [member]
Analysis of income and expense [Line Items]
Intangible assets amortization	1,610,250	58,048	1,502,317	1,484,532
Depreciation expense	$ 3,589,890	$ 129,412	$ 3,507,849	$ 3,140,902

Profit Before Income Tax - Su_7

Profit Before Income Tax - Summary of Operating Expenses Directly Related to Investment Properties (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Direct operating expense from investment property [abstract]
Direct operating expenses of investment properties that generated rental income	$ 1,422,463	$ 51,278	$ 1,121,854	$ 1,232,826

Profit Before Income Tax - Su_8

Profit Before Income Tax - Summary of Employee Benefits Expense (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Post-employment benefits
Defined contribution plans	$ 3,489,642	$ 125,798	$ 2,979,167	$ 3,148,209
Defined benefit plans	214,599	7,736	217,186	277,041
Post-employment benefits	3,704,241	133,534	3,196,353	3,425,250
Equity-settled share-based payments	699,211	25,206	955,575	871,699
Other employee benefits	90,412,118	3,259,269	76,648,412	70,279,752
Employee benefits expense	94,815,570	3,418,009	80,800,340	74,576,701
Operating costs [member]
Post-employment benefits
Employee benefits expense	61,555,563	2,219,018	52,526,164	49,173,778
Operating expense [member]
Post-employment benefits
Employee benefits expense	$ 33,260,007	$ 1,198,991	$ 28,274,176	$ 25,402,923

Profit Before Income Tax - Addi

Profit Before Income Tax - Additional Information (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2020USD ($)
Analysis of income and expense [Line Items]
Percentage of employees' compensation	0.19%	0.19%	0.20%	0.20%
Percentage of remuneration to directors	0.30%	0.30%	0.40%	0.40%
Difference Between Employee Compensation Benefits And Director Remuneration Adjusted In Net Profit	$ 818	$ 29	$ 3	$ 29
Bottom of range [member]
Analysis of income and expense [Line Items]
Percentage of employees' compensation	0.01%	0.01%
Top of range [member]
Analysis of income and expense [Line Items]
Percentage of employees' compensation	1.00%	1.00%
Percentage of remuneration to directors	0.75%	0.75%

Profit Before Income Tax - Su_9

Profit Before Income Tax - Summary of Employees' Compensation and Remuneration to Directors (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Analysis Of Income And Expense [line items]
Employees' compensation	$ 121,935	$ 4,396	$ 54,909
Remuneration to directors	$ 195,095	$ 7,033	109,818
Resolved by the board of directors [member]
Analysis Of Income And Expense [line items]
Employees' compensation			54,909	$ 34,400
Remuneration to directors			109,000	68,800
Recognized in the consolidated financial statements [member]
Analysis Of Income And Expense [line items]
Employees' compensation			54,909	34,400
Remuneration to directors			$ 109,818	$ 68,803

Income Tax - Summary of Major C

Income Tax - Summary of Major Components of Income Tax Expense (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Current income tax
In respect of the current year	$ 14,533,570	$ 523,921	$ 6,807,882	$ 5,002,954
Income tax on unappropriated earnings	3,684,138	132,810	680,649	19,115
Changes in estimate for prior years	(129,152)	(4,656)	(472,512)	(352,579)
Current income tax	18,088,556	652,075	7,016,019	4,669,490
Deferred income tax
In respect of the current year	(95,906)	(3,457)	212,338	563,512
Changes in tax rates	18,337	660		54,072
Changes in estimate for prior years	16,625	600	(103,021)	(213,758)
Effect of foreign currency exchange differences	(83,840)	(3,022)	(8,438)	(62,070)
Deferred income tax	(144,784)	(5,219)	100,879	341,756
Income tax expense recognized in profit or loss	$ 17,943,772	$ 646,856	$ 7,116,898	$ 5,011,246

Income Tax - Summary of Reconci

Income Tax - Summary of Reconciliation of Income Tax Expense (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Major components of tax expense (income) [abstract]
Profit before income tax	$ 80,193,769	$ 2,890,906	$ 35,768,798	$ 23,279,811
Income tax expense calculated at the statutory rates	33,697,736	1,214,771	16,907,904	11,802,811
Nontaxable expense in determining taxable income	357,936	12,903	316,619	459,133
Tax-exempt income	(14,578,355)	(525,536)	(387,212)	(495,883)
Additional income tax on unappropriated earnings	3,684,138	132,810	680,649	19,115
Income tax credits	(1,654,821)	(59,655)	(1,191,387)	(898,198)
The origination and reversal of temporary differences	78,544	2,831	(6,033,652)	(3,594,774)
Income tax adjustments on prior years	(112,527)	(4,056)	(472,512)	(352,579)
Unrecognized deferred tax liability for temporary differences associated with investments	(6,135,120)	(221,165)	(2,616,917)	(1,993,561)
Unrecognized loss carryforwards	288,025	10,383
Realized investment loss on merger of subsidiary			(138,890)
Withholding tax	87,175	3,143	52,296	65,182
Land value increment tax	117,341	4,230
Capital gains tax	2,113,700	76,197
Income tax expense recognized in profit or loss	$ 17,943,772	$ 646,856	$ 7,116,898	$ 5,011,246

Income Tax - Additional Informa

Income Tax - Additional Information (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of income taxes [line items]
Taxable temporary differences associated with the investments in subsidiaries for which no deferred tax liabilities recognized	$ 39,480,927	$ 1,423,249	$ 33,474,725
Subsidiaries [member] | China [member]
Disclosure of income taxes [line items]
Reduction tax rate	15.00%

Income Tax - Summary of Income

Income Tax - Summary of Income Tax Recognized Directly in Equity (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Current and deferred tax relating to items charged or credited directly to equity [abstract]
Deferred income tax related to employee share options	$ (9)	$ 0	$ (1,159)	$ 1,404

Income Tax - Summary of Incom_2

Income Tax - Summary of Income Tax Recognized in Other Comprehensive Income (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Income tax relating to components of other comprehensive income [abstract]
Deferred income tax Related to remeasurement of defined benefit plans	$ (19,319)	$ (696)	$ 114,559	$ 74,308
Unrealized loss on equity instruments at fair value through other comprehensive income	(160,084)	(5,771)	(237,460)	(78,124)
Income tax recognized in other comprehensive income	$ (179,403)	$ (6,467)	$ (122,901)	$ (3,816)

Income Tax - Summary of Current

Income Tax - Summary of Current Tax Assets and Liabilities (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Current tax assets
Tax refund receivable	$ 207,272	$ 7,472	$ 303,265
Prepaid income tax	334,908	12,073	399,555
Current tax assets	542,180	19,545	702,820
Current tax liabilities
Income tax payable	$ 16,362,350	$ 589,847	$ 6,514,502

Income Tax - Summary of Movemen

Income Tax - Summary of Movements of Deferred Tax Assets and Deferred Tax Liabilities (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Recognized in Profit or Loss	$ 144,784	$ 5,219	$ (100,879)	$ (341,756)
Recognized in Other Comprehensive Income	(179,403)	(6,467)	(122,901)	(3,816)
Recognized in Equity	(9)	0	(1,159)	1,404
Deferred tax assets [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Balance at January 1	5,477,373	197,455	4,707,704	5,108,357
Recognized in Profit or Loss	627,367	22,616	378,400	(466,954)
Recognized in Other Comprehensive Income	(19,319)	(696)	114,559	74,308
Recognized in Equity	(7)	0	(999)	1,160
Exchange Differences	(56,432)	(2,035)	(54,210)	(72,379)
Acquisitions Through Business Combinations			630,135	63,212
Disposal of Subsidiary	(659,972)	(23,792)	(298,216)
Balance at December 31	5,369,010	193,548	5,477,373	4,707,704
Deferred tax liabilities [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Balance at January 1	7,121,027	256,706	5,772,237	5,806,713
Recognized in Profit or Loss	482,583	17,397	479,278	(125,197)
Recognized in Other Comprehensive Income	160,084	5,771	237,460	78,124
Recognized in Equity	2	0	160	(244)
Exchange Differences	27,400	987	(30,241)	(10,267)
Acquisitions Through Business Combinations			662,928	23,108
Disposal of Subsidiary	(200,899)	(7,242)	(795)
Balance at December 31	7,590,197	273,619	7,121,027	5,772,237
Property, plant and equipment [member] | Deferred tax assets [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Balance at January 1	629,702	22,700	544,844	689,790
Recognized in Profit or Loss	(186,443)	(6,721)	4,632	(119,972)
Exchange Differences	(7,178)	(259)	12,435	(25,023)
Acquisitions Through Business Combinations			81,773	49
Disposal of Subsidiary	(345,104)	(12,441)	(13,982)
Balance at December 31	90,977	3,279	629,702	544,844
Property, plant and equipment [member] | Deferred tax liabilities [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Balance at January 1	5,980,387	215,587	5,206,617	5,236,104
Recognized in Profit or Loss	165,628	5,971	427,465	(39,379)
Exchange Differences	(42,437)	(1,530)	(29,248)	(7,074)
Acquisitions Through Business Combinations			375,553	16,966
Disposal of Subsidiary	(186,834)	(6,735)
Balance at December 31	5,916,744	213,293	5,980,387	5,206,617
Defined benefit obligation [member] | Deferred tax assets [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Balance at January 1	1,370,455	49,404	1,078,583	1,064,824
Recognized in Profit or Loss	(115,707)	(4,171)	(36,633)	(57,746)
Recognized in Other Comprehensive Income	(19,319)	(696)	114,559	74,308
Exchange Differences	(47,276)	(1,704)	1,005	(2,803)
Acquisitions Through Business Combinations			212,941
Balance at December 31	1,188,153	42,833	1,370,455	1,078,583
Mandatorily at fair value through profit or loss [member] | Deferred tax assets [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Balance at January 1	112,259	4,047	259,507	211,556
Recognized in Profit or Loss	77,593	2,797	(138,045)	47,991
Exchange Differences	(502)	(18)	(7)	(40)
Acquisitions Through Business Combinations			2,085
Disposal of Subsidiary			(11,281)
Balance at December 31	189,350	6,826	112,259	259,507
Mandatorily at fair value through profit or loss [member] | Deferred tax liabilities [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Balance at January 1	6,317	228	9,192	4,535
Recognized in Profit or Loss	6,274	226	(2,942)	4,706
Exchange Differences	(11)	(1)	67	(49)
Balance at December 31	12,580	453	6,317	9,192
Other temporary differences [member] | Deferred tax assets [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Balance at January 1	2,407,910	86,803	1,744,949	1,838,746
Recognized in Profit or Loss	679,492	24,495	679,197	(84,377)
Recognized in Equity	(7)	0	(999)	1,160
Exchange Differences	52,399	1,889	(45,169)	(24,906)
Acquisitions Through Business Combinations			150,291	14,326
Disposal of Subsidiary	(269,080)	(9,700)	(120,359)
Balance at December 31	2,870,714	103,487	2,407,910	1,744,949
Other temporary differences [member] | Deferred tax liabilities [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Balance at January 1	1,134,323	40,891	556,428	566,074
Recognized in Profit or Loss	310,681	11,200	54,755	(90,524)
Recognized in Other Comprehensive Income	160,084	5,771	237,460	78,124
Recognized in Equity	2	0	160	(244)
Exchange Differences	69,848	2,518	(1,060)	(3,144)
Acquisitions Through Business Combinations			287,375	6,142
Disposal of Subsidiary	(14,065)	(507)	(795)
Balance at December 31	1,660,873	59,873	1,134,323	556,428
Temporary differences [member] | Deferred tax assets [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Balance at January 1	4,520,326	162,954	3,627,883	3,804,916
Recognized in Profit or Loss	454,935	16,400	509,151	(214,104)
Recognized in Other Comprehensive Income	(19,319)	(696)	114,559	74,308
Recognized in Equity	(7)	0	(999)	1,160
Exchange Differences	(2,557)	(92)	(31,736)	(52,772)
Acquisitions Through Business Combinations			447,090	14,375
Disposal of Subsidiary	(614,184)	(22,141)	(145,622)
Balance at December 31	4,339,194	156,425	4,520,326	3,627,883
Unused tax losses [member] | Deferred tax assets [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Balance at January 1	527,666	19,022	542,781	672,275
Recognized in Profit or Loss	187,981	6,777	(44,651)	(166,128)
Exchange Differences	(31,077)	(1,121)	(915)	(12,203)
Acquisitions Through Business Combinations			183,045	48,837
Disposal of Subsidiary	(45,788)	(1,651)	(152,594)
Balance at December 31	638,782	23,027	527,666	542,781
Unused tax credits [member] | Deferred tax assets [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Balance at January 1	429,381	15,479	537,040	631,166
Recognized in Profit or Loss	(15,549)	(561)	(86,100)	(86,722)
Exchange Differences	(22,798)	(822)	(21,559)	(7,404)
Balance at December 31	$ 391,034	$ 14,096	$ 429,381	$ 537,040

Income Tax - Summary of Unrecog

Income Tax - Summary of Unrecognized Deferred Tax Assets Related to Loss Carry-forward, Investment Credits and Deductible Temporary Differences (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of temporary difference, unused tax losses and unused tax credits [abstract]
Loss carry-forward	$ 1,340,849	$ 48,336	$ 1,497,056
Investment credits	44,244	1,595	49,611
Deductible temporary differences	241,249	8,697	377,242
Unrecognized deferred tax assets	$ 1,626,342	$ 58,628	$ 1,923,909

Income Tax - Summary of Unused

Income Tax - Summary of Unused Loss Carry-forward (Detail) - Dec. 31, 2021 $ in Thousands, $ in Thousands	TWD ($)	USD ($)
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Unused loss carry-forward	$ 1,979,629	$ 71,363
2022 [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Unused loss carry-forward	243,136	8,765
2023 [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Unused loss carry-forward	192,254	6,930
2024 [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Unused loss carry-forward	171,664	6,188
2025 [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Unused loss carry-forward	185,524	6,688
2026 and thereafter [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Unused loss carry-forward	$ 1,187,051	$ 42,792

Income Tax - Summary of Unuse_2

Income Tax - Summary of Unused Investment Credits (Detail) - 12 months ended Dec. 31, 2021 $ in Thousands, $ in Thousands	TWD ($)	USD ($)
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Remaining Creditable Amount	$ 1,979,629	$ 71,363
Unused tax credits [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Remaining Creditable Amount	$ 435,278	15,691
Purchase of machinery and equipment [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Expiry Year	2026
Purchase of machinery and equipment [member] | Unused tax credits [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Remaining Creditable Amount	$ 370,360	13,351
Others [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Expiry Year	2026 and thereafter
Others [member] | Unused tax credits [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Remaining Creditable Amount	$ 64,918	$ 2,340

Income Tax - Summary of Project

Income Tax - Summary of Projects were Exempted From Income Tax (Detail) - Construction and expansion of 2009 [member] - ASE Test, Inc. [member]	12 Months Ended
	Dec. 31, 2021
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Tax-exemption period, start date	2018-01
Tax-exemption period, end date	2022-12

Earnings Per Share - Summary of

Earnings Per Share - Summary of Earnings and Weighted Average Number of Ordinary Shares Outstanding in Computation of Earnings Per Share (Detail) shares in Thousands, $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)shares	Dec. 31, 2021USD ($)shares	Dec. 31, 2020TWD ($)shares	Dec. 31, 2019TWD ($)shares
Earnings per share [line items]
Profit for the year attributable to owners of the Company	$ 60,150,167	$ 2,168,353	$ 26,970,580	$ 17,060,591
Effect of potentially dilutive ordinary shares:
Potential ordinary shares of the subsidiary	(1,056,778)	(38,096)	(521,073)	(385,865)
Earnings used in the computation of diluted earnings per share	$ 59,093,389	$ 2,130,257	$ 26,449,507	$ 16,674,726
Weighted average number of ordinary shares in the computation of basic earnings per share	4,305,348	4,305,348	4,265,732	4,251,964
Effect of potentially dilutive ordinary shares:
Employee share options	58,113	58,113	22,086	10,232
Employees' compensation	1,264	1,264	815	570
Employee restricted stock awards	943	943
Weighted average number of ordinary shares in computation of diluted earnings per share	4,365,668	4,365,668	4,288,633	4,262,766

Earnings Per Share - Additional

Earnings Per Share - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2021
Earnings per share [line items]
Number of shares represented by each ADS	2

Share-based Payment Arrangeme_3

Share-based Payment Arrangements - Additional Information (Detail)	Dec. 27, 2019	Sep. 30, 2020shares	Nov. 30, 2019shares	Dec. 31, 2021TWD ($)shares$ / shares	Dec. 31, 2021USD ($)shares$ / shares	Dec. 31, 2020TWD ($)shares$ / shares	Dec. 31, 2019TWD ($)shares$ / shares	Dec. 31, 2021USD ($)$ / shares
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Compensation cost of employee share options				$ 699,211,000	$ 25,206,000	$ 955,575,000	$ 871,699,000
Employee restricted stock awards plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Stock Issued during the period ,Restricted stock award ,shares				15,000,000	15,000,000
Par value per share | (per share)				$ 10				$ 0.36
Fair value of the employee restricted stock award				$ 92.4	$ 3.33
Exercise price, per share | $ / shares						$ 0
USIE option plans [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Capital surplus decreased | $						$ 1,120,111,000	981,078,000
Retained earnings decreased | $						392,447,000
USISH option plans [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Capital surplus decreased				$ 58,448,000		$ 1,010,219,000	$ 105,785,000	$ 2,107,000
Options granted				0	0	1,140,000	17,167,000
Number of equity instruments other than options granted				281,000	281,000	672,000	6,156,000
USISH option plans [member] | Share Option [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Options granted			17,167,000
USISH option plans [member] | Bottom of range [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Valid term of share option plans			3.0
USISH option plans [member] | Weighted average [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Valid term of share option plans			4.0
ASE Inc. option plans [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Share option to purchase of ordinary shares				0.5	0.5
Weighted average exercise price of share options | $ / shares							$ 69.3
The Company Option Plans [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Valid term of share option plans				10 years	10 years
Percentage of cash dividend per ordinary share exceeds market price				1.50%	1.50%
Weighted average exercise price of share options | (per share)				$ 108.8	$ 3.9	$ 68.5
USISH core employees stock ownership plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Options granted			6,156,000
Share based compensation number of additional shares to be granted			6,403,000
USISH core employees stock ownership plan [Member] | Phase One [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Valid term of share option plans	4.5 years
USISH core employees stock ownership plan [Member] | Phase Two [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Valid term of share option plans	3.5 years
USISH core employees stock ownership plan [Member] | Phase Three [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Valid term of share option plans	2.5 years
USISH second share option plan [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Number of shares granted		1,140,000
USISH second share option plan [member] | Phase One [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Valid term of share option plans		1.2 years
USISH second share option plan [member] | Phase Two [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Valid term of share option plans		2.2 years
USISH second share option plan [member] | Phase Three [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Valid term of share option plans		3.2 years
USISH second share option plan [member] | Bottom of range [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Valid term of share option plans		2.2
USISH second share option plan [member] | Weighted average [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Valid term of share option plans		3.2
USISH second share option plan [member] | Top of range [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Valid term of share option plans		4.2 years
USISH restricted share plan [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Valid term of share option plans		2 years
Number of equity instruments other than options granted		425,000
Period of lock in of ordinary shares to be issued upon satisfaction of performance conditions		1 year 3 months 18 days

Share-based Payment Arrangeme_4

Share-based Payment Arrangements - Summary of Information About ASE Inc. Option Plans (Detail) - The Company Option Plans [member] shares in Thousands	12 Months Ended
	Dec. 31, 2021shares$ / shares	Dec. 31, 2020shares$ / shares	Dec. 31, 2019shares$ / shares
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Number of options, beginning balance | shares	144,767	170,786	183,814
Number of options, forfeited | shares	(5,907)	(3,949)	(4,214)
Number of options, expired | shares	0	(1,006)
Number of options, exercised | shares	(42,058)	(21,064)	(8,814)
Number of options, Ending balance | shares	96,802	144,767	170,786
Number of options, exercisable, end of year | shares	49,696	67,388	33,822
Weighted average exercise price, Beginning balance | $ / shares	$ 56.9	$ 57	$ 58.1
Weighted average exercise price, Options expired | $ / shares	0	40.8
Weighted average exercise price, Options forfeited | $ / shares	52.3	58	61.8
Weighted average exercise price, Options exercised | $ / shares	61.4	49.2	48.4
Weighted average exercise price, Ending balance | $ / shares	53.3	56.9	57
Weighted average exercise price, Options exercisable, end of year | $ / shares	$ 55.5	$ 61.4	$ 63.5

Share-based Payment Arrangeme_5

Share-based Payment Arrangements - Summary of ASE Inc. Option Plans Outstanding Share Options (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
ASE Inc. option plans [member] | Fourth share options exercise price [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Range of Exercise Price Per Share		$ 45.2
Weighted Average Remaining Contractual Life (Years)		3 months 18 days
ASE Inc. option plans [member] | Fifth share options exercise price [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Range of Exercise Price Per Share	$ 73	$ 73
Weighted Average Remaining Contractual Life (Years)	3 years 8 months 12 days	4 years 8 months 12 days
The Company Option Plans [member] | First share options exercise price [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Range of Exercise Price Per Share	$ 51	$ 52.9
Weighted Average Remaining Contractual Life (Years)	6 years 10 months 24 days	7 years 10 months 24 days

Share-based Payment Arrangeme_6

Share-based Payment Arrangements - Summary of Information About USIE Option Plans (Detail) - USIE option plans [member] shares in Thousands	12 Months Ended
	Dec. 31, 2020shares$ / shares	Dec. 31, 2019shares$ / shares
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Number of options, beginning balance | shares	8,349	16,711
Number of options, forfeited | shares	(7)
Number of options, exercised | shares	(8,342)	(8,362)
Number of options, Ending balance | shares		8,349
Number of options, exercisable, end of year | shares		8,349
Weighted average exercise price, Beginning balance | $ / shares	$ 2.3	$ 2.1
Weighted average exercise price, Options exercised | $ / shares	2.9	2
Weighted average exercise price, Options forfeited | $ / shares	$ 2.3
Weighted average exercise price, Ending balance | $ / shares		2.3
Weighted average exercise price, Options exercisable, end of year | $ / shares		$ 2.3

Share-based Payment Arrangeme_7

Share-based Payment Arrangements - Summary of Information About USISH Option Plans (Detail) - USISH option plans [member] ¥ / shares in Units, shares in Thousands	12 Months Ended
	Dec. 31, 2021CNY (¥)shares¥ / shares	Dec. 31, 2020CNY (¥)shares¥ / shares	Dec. 31, 2019shares$ / shares¥ / shares	Dec. 31, 2019CNY (¥)shares¥ / shares
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Number of options, beginning balance	31,266	35,077		21,537
Number of options, granted	0	1,140		17,167
Number of options, forfeited	(952)	(636)		(463)
Number of options, exercised	(828)	(4,315)		(3,164)
Number of options, Ending balance	29,486	31,266		35,077
Number of options, exercisable, end of year	19,249	13,416	13,694	13,694
Weighted average exercise price, Beginning balance | ¥ / shares	¥ 14.6	¥ 14.5		¥ 15.5
Weighted average exercise price options granted | (per share)	0	21.7	$ 13.3
Weighted average exercise price, Options forfeited | ¥ / shares	14.5	14		15.4
Weighted average exercise price options exercised | ¥ / shares	13.8	15.5		15.5
Weighted average exercise price, Ending balance | ¥ / shares	14.2	14.6		14.5
Weighted average exercise price, Options exercisable, end of year | ¥ / shares	¥ 14.8	¥ 15.5	$ 15.5	¥ 15.5
Fair value of options granted | ¥	¥ 0
Bottom of range [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Fair value of options granted | ¥		¥ 7.03		¥ 6.27
Top of range [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Fair value of options granted | ¥		¥ 8.93		¥ 8.35

Share-based Payment Arrangeme_8

Share-based Payment Arrangements - Summary of USISH's outstanding share options balance sheet (Detail) - USISH Option Plans [member] - ¥ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share options [Member]
Disclosure of range of exercise prices of outstanding share options [Line Items]
Range of Exercise Price Per Share	¥ 15.5	¥ 15.5
Weighted average remaining contractual life of outstanding share options	3 years 10 months 24 days	4 years 10 months 24 days
Stock option plans [Member]
Disclosure of range of exercise prices of outstanding share options [Line Items]
Range of Exercise Price Per Share	¥ 12.7	¥ 13.3
Weighted average remaining contractual life of outstanding share options	2 years 10 months 24 days	3 years 10 months 24 days
2020 Share Options [Member]
Disclosure of range of exercise prices of outstanding share options [Line Items]
Range of Exercise Price Per Share	¥ 21.2	¥ 21.7
Weighted average remaining contractual life of outstanding share options	2 years 10 months 24 days	3 years 10 months 24 days

Share-based Payment Arrangeme_9

Share-based Payment Arrangements - Summary of Information About Restricted Shares (Detail)	12 Months Ended
	Dec. 31, 2021shares¥ / shares	Dec. 31, 2020shares¥ / shares	Dec. 31, 2019shares¥ / shares
Disclosure of terms and conditions of share-based payment arrangement [line items]
Options exercisable, end of year | shares	0
Exercise Price Per Share, Options exercisable, end of year	¥ 0
USISH option plans [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Balance at January  1 | shares	5,547,000	6,156,000
Options granted | shares	281,000	672,000	6,156,000
Options exercised | shares	(1,780,000)	(1,281,000)
Options forfeited | shares	(483,000)
Balance at December  31 | shares	3,565,000	5,547,000	6,156,000
Fair value of options granted (RMB)	¥ 11.78	¥ 18.55	¥ 13.47
Exercise Price Per Share, Begining	12.2	13.3
Exercise Price Per Share, Options granted	0	4.9	13.3
Exercise Price Per Share, Options exercised	12.7	13.2
Exercise Price Per Share, Options forfeited	12.1
Exercise Price Per Share, Ending	¥ 10.2	¥ 12.2	¥ 13.3

Share-based Payment Arrangem_10

Share-based Payment Arrangements - Summary of Outstanding Restricted Shares At Balance Sheet (Detail) - USISH option plans [member]	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
2019 restricted stocks [Member]
Dislcosure of Range Exercise Prices of Outstanding Restricted Shares [Line Items]
Range of Exercise Price Per Share	12.7	13.2
Remaining Contractual Life (Years)	2 years 3 months 18 days	3 years 3 months 18 days
2020 restricted stocks [Member]
Dislcosure of Range Exercise Prices of Outstanding Restricted Shares [Line Items]
Remaining Contractual Life (Years)	8 months 12 days	1 year 8 months 12 days
2021 restricted stocks [Member]
Dislcosure of Range Exercise Prices of Outstanding Restricted Shares [Line Items]
Remaining Contractual Life (Years)	1 year 8 months 12 days

Share-based Payment Arrangem_11

Share-based Payment Arrangements - Summary of Fair Value using Trinomial Tree Model and Inputs (Detail)	12 Months Ended
	Dec. 31, 2021Years¥ / shares	Dec. 31, 2020Yearsyr¥ / shares	Dec. 31, 2019yrYears¥ / shares
Trinomial Tree Model [member] | USISH stock option plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Share price at the grant date			¥ 15.84
Exercise price			13.34
Trinomial Tree Model [member] | USISH two thousand and twenty share options plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Share price at the grant date		¥ 21.55
Exercise price		21.65
Binomial Method [Member] | USISH core employees stock ownership plan restricted shares amended in 2020 [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Share price at the grant date			16.60
Exercise price			¥ 13.34
Expected volatility			57.21%
Lock-up periods | Years			1
Risk free interest rate			1.55%
Binomial Method [Member] | USISH core employees stock ownership plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Share price at the grant date			¥ 16.30
Exercise price			¥ 13.34
Expected volatility			47.77%
Lock-up periods | Years			1
Risk free interest rate			2.70%
Binomial Method [Member] | USISH employee stock ownership restricted stock ownership plan amendment 2020 [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Share price at the grant date		¥ 24.30
Expected volatility		56.97%
Lock-up periods | Years		1.3
Risk free interest rate		2.63%
Binomial Method [Member] | USISH employee stock ownership restricted stock ownership plan amendment 2021 [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Share price at the grant date	¥ 14.65
Expected volatility	47.15%
Lock-up periods | Years	1.3
Risk free interest rate	2.34%
Bottom of range [member] | Trinomial Tree Model [member] | USISH stock option plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Expected volatility			45.07%
Expected lives | yr			3
Risk free interest rate			2.80%
Bottom of range [member] | Trinomial Tree Model [member] | USISH two thousand and twenty share options plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Expected volatility		48.14%
Expected lives | yr		2.2
Risk free interest rate		2.80%
Top of range [member] | Trinomial Tree Model [member] | USISH stock option plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Expected volatility			51.80%
Expected lives | yr			5
Risk free interest rate			2.97%
Top of range [member] | Trinomial Tree Model [member] | USISH two thousand and twenty share options plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Expected volatility		53.57%
Expected lives | yr		4.2
Risk free interest rate		2.99%

Business Combinations - Summary

Business Combinations - Summary of Subsidiary Acquired (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)
AMPI [member]
Disclosure of detailed information about business combination [Line Items]
Principal Activity	Engaged in the manufacturing of integrated circuit
Date of Acquisition	Apr. 30, 2019
Proportion of Voting Equity Interests Acquired	50.97%	50.97%
Cash Consideration	$ 250,000
ASEEE [member]
Disclosure of detailed information about business combination [Line Items]
Principal Activity	Engaged in the production of embedded substrate
Date of Acquisition	Apr. 26, 2019
Proportion of Voting Equity Interests Acquired	51.00%	51.00%
Cash Consideration	$ 0
USIPL [member]
Disclosure of detailed information about business combination [Line Items]
Principal Activity	Engaged in the design and manufacturing of electronic components and new electronic applications
Date of Acquisition	Oct. 31, 2019
Proportion of Voting Equity Interests Acquired	60.00%	60.00%
Cash Consideration	$ 313,057
FAFG [member]
Disclosure of detailed information about business combination [Line Items]
Principal Activity	Holding company and the group engaged in the design and manufacturing of electronic components
Date of Acquisition	Dec. 1, 2020
Proportion of Voting Equity Interests Acquired	100.00%	100.00%
Cash Consideration	$ 12,443,637
ITGEU [member]
Disclosure of detailed information about business combination [Line Items]
Principal Activity	Trading company
Date of Acquisition	Oct. 21, 2021
Proportion of Voting Equity Interests Acquired	100.00%	100.00%
Cash Consideration	$ 50,368	$ 1,816
SER [Member]
Disclosure of detailed information about business combination [Line Items]
Principal Activity	Engaged in the design and manufacturing of electronic components
Date of Acquisition	Nov. 2, 2021
Proportion of Voting Equity Interests Acquired	100.00%	100.00%
Cash Consideration	$ 217,919	$ 7,856

Business Combinations - Additio

Business Combinations - Additional Information (Detail) $ in Thousands, $ in Thousands	1 Months Ended			12 Months Ended
	Jul. 31, 2019USD ($)	May 31, 2019TWD ($)	Apr. 30, 2019TWD ($)shares	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)shares	Dec. 31, 2020USD ($)	Dec. 31, 2019TWD ($)	Oct. 01, 2021
Disclosure of subsidiaries [Line Items]
Significant unobservable inputs discount rate				31.00%	31.00%
Revenue from continuing operations				$ 570,363,380	$ 20,561,045	$ 497,146,285		$ 413,782,708
Profit from continuing operations				$ 62,277,713	$ 2,245,051	28,833,916		$ 18,030,506
Call option on the remaining non-controlling interests				40.00%	40.00%
Gain recognized from remeasuring fair value of equity interest before business combination			$ 243,057
USIFR [Member]
Disclosure of subsidiaries [Line Items]
Percentage of shareholdings acquired by subsidiary									100.00%
Percentage of voting equity interests acquired									100.00%
Proceeds From Sale Of Restricted Investments						385,735
Proceeds from Decommissioning Trust Fund Assets						294,244
Proceed From the issue of Other investment						91,491
Top of range [member]
Disclosure of subsidiaries [Line Items]
Contingent consideration recognised as of acquisition date						42,805
USIFR [Member]
Disclosure of subsidiaries [Line Items]
Consideration paid in cash for shares						10,800,558	$ 368,753
Arrangement for contingent consideration by making deposit to trust fund						$ 294,244	$ 10,122
UGPL [Member]
Disclosure of subsidiaries [Line Items]
Number of shares issued | shares						25,940
FAFG [Member]
Disclosure of subsidiaries [Line Items]
Percentage of shareholdings acquired by subsidiary				100.00%	100.00%
Percentage of Ownership (%)						100.00%	100.00%
Percentage of voting equity interests acquired				100.00%	100.00%
A S E Embedded Electronics Inc [Member]
Disclosure of subsidiaries [Line Items]
Consideration paid in cash for shares		$ 1,500,000	1,147,595
Gain recognized from remeasuring fair value of equity interest before business combination			76,655
Ordinary shares acquired			$ 150,000
Percentage of Ownership (%)	100.00%
A S E Embedded Electronics Inc [Member] | TDK Corporation [Member]
Disclosure of subsidiaries [Line Items]
Ordinary shares acquired	$ 6,000
ASE Test, Inc. [member]
Disclosure of subsidiaries [Line Items]
Percentage of ownership interest in joint venture			50.97%
ASE Test, Inc. [member] | Private Placement [Member]
Disclosure of subsidiaries [Line Items]
Shares subscribed | shares			100,000
Consideration paid in cash for shares			$ 250,000
UGPL [Member]
Disclosure of subsidiaries [Line Items]
Percentage of shareholdings acquired by subsidiary				60.00%	60.00%
Percentage of voting equity interests acquired				60.00%	60.00%

Business Combinations - Summa_2

Business Combinations - Summary of Consideration Transferred in business combination (Detail) - Dec. 31, 2021 $ in Thousands, $ in Thousands	TWD ($)	USD ($)
AMPI [member]
Disclosure of detailed information about business combination [line items]
Fair value of identifiable net assets acquired	$ 849,863
AMPI [member] | Consideration transferred [member]
Disclosure of detailed information about business combination [line items]
Cash	250,000
Fair value of identifiable net assets acquired	250,000
ASEEE [member]
Disclosure of detailed information about business combination [line items]
Fair value of identifiable net assets acquired	215,233
ASEEE [member] | Consideration transferred [member]
Disclosure of detailed information about business combination [line items]
Cash	0
Fair value of identifiable net assets acquired	0
USIPL [member]
Disclosure of detailed information about business combination [line items]
Fair value of identifiable net assets acquired	331,192
USIPL [member] | Consideration transferred [member]
Disclosure of detailed information about business combination [line items]
Cash	313,057
Fair value of identifiable net assets acquired	313,057
FAFG [member]
Disclosure of detailed information about business combination [line items]
Cash	11,094,802
Fair value of identifiable net assets acquired	9,876,084
FAFG [member] | Consideration transferred [member]
Disclosure of detailed information about business combination [line items]
Cash	11,094,802
Equity instrument issued	1,734,570
Contingent consideration arrangement	(385,735)
Fair value of identifiable net assets acquired	12,443,637
ITGEU [member]
Disclosure of detailed information about business combination [line items]
Fair value of identifiable net assets acquired	83,482	$ 3,009
ITGEU [member] | Consideration transferred [member]
Disclosure of detailed information about business combination [line items]
Cash	50,368	1,816
Fair value of identifiable net assets acquired	50,368	1,816
SER [Member]
Disclosure of detailed information about business combination [line items]
Fair value of identifiable net assets acquired	217,919	7,856
SER [Member] | Consideration transferred [member]
Disclosure of detailed information about business combination [line items]
Cash	217,919	7,856
Fair value of identifiable net assets acquired	$ 217,919	$ 7,856

Business Combinations - Summa_3

Business Combinations - Summary of Assets Acquired and Liabilities Assumed at the Date of Acquisition (Detail) - Dec. 31, 2021 $ in Thousands, $ in Thousands	TWD ($)	USD ($)
AMPI [member]
Disclosure of detailed information about business combination [Line Items]
Cash and cash equivalents	$ 349,496
Trade and other receivables	371,144
Inventories	403,887
Property, plant and equipment	683,207
Intangible assets	128,900
Others	237,766
Trade and other payables	(224,295)
Borrowings and bonds payables	(951,519)
Others	(148,723)
Fair value of identifiable net assets acquired	849,863
ASEEE [member]
Disclosure of detailed information about business combination [Line Items]
Cash and cash equivalents	23,197
Trade and other receivables	5,732
Inventories	11,033
Property, plant and equipment	1,361,572
Intangible assets	290,757
Others	317,888
Trade and other payables	(133,278)
Borrowings and bonds payables	(1,371,395)
Others	(290,273)
Fair value of identifiable net assets acquired	215,233
USIPL [member]
Disclosure of detailed information about business combination [Line Items]
Cash and cash equivalents	108,718
Trade and other receivables	58,713
Inventories	229
Property, plant and equipment	525,048
Intangible assets	11,704
Others	99,112
Trade and other payables	(217,887)
Borrowings and bonds payables	(190,737)
Others	(63,708)
Fair value of identifiable net assets acquired	331,192
FAFG [member]
Disclosure of detailed information about business combination [Line Items]
Cash and cash equivalents	2,349,164
Trade and other receivables	4,434,296
Inventories	4,836,819
Property, plant and equipment	2,882,720
Intangible assets	1,541,155
Others	1,919,118
Trade and other payables	(4,575,720)
Borrowings and bonds payables	(356,417)
Others	(3,155,051)
Fair value of identifiable net assets acquired	9,876,084
ITGEU
Disclosure of detailed information about business combination [Line Items]
Cash and cash equivalents	68,719	$ 2,477
Trade and other receivables	41,832	1,508
Property, plant and equipment	94	3
Intangible assets	32	1
Others	2,828	102
Trade and other payables	(29,165)	(1,051)
Others	(858)	(31)
Fair value of identifiable net assets acquired	83,482	3,009
SER [Member]
Disclosure of detailed information about business combination [Line Items]
Cash and cash equivalents	18,850	680
Trade and other receivables	40,671	1,466
Inventories	375,912	13,551
Property, plant and equipment	37,672	1,357
Intangible assets	368	14
Others	186,377	6,719
Trade and other payables	(214,883)	(7,746)
Others	(227,048)	(8,185)
Fair value of identifiable net assets acquired	$ 217,919	$ 7,856

Business Combinations - Summa_4

Business Combinations - Summary of Goodwill Recognized on Acquisitions (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019TWD ($)	Dec. 31, 2018TWD ($)
Disclosure of detailed information about business combination [Line Items]
Goodwill	$ 52,072,413	$ 1,877,160	$ 52,709,053	$ 1,900,110	$ 50,198,436	$ 49,974,446
AMPI [member]
Disclosure of detailed information about business combination [Line Items]
Total consideration	250,000
Add: Fair value of investments previously owned	315,925
Add: Non-controlling interests	416,716
Less: Fair value of identifiable net assets acquired	(849,863)
Goodwill	132,778
ASEEE [member]
Disclosure of detailed information about business combination [Line Items]
Total consideration	0
Add: Fair value of investments previously owned	117,609
Add: Non-controlling interests	105,464
Less: Fair value of identifiable net assets acquired	(215,233)
Goodwill	7,840
USIPL [member]
Disclosure of detailed information about business combination [Line Items]
Total consideration	313,057
Add: Fair value of investments previously owned	0
Add: Non-controlling interests	142,494
Less: Fair value of identifiable net assets acquired	(331,192)
Goodwill	124,359
FAFG [member]
Disclosure of detailed information about business combination [Line Items]
Total consideration	12,443,637
Add: Non-controlling interests	289
Less: Fair value of identifiable net assets acquired	(9,876,084)
Goodwill	2,567,842
ITGEU
Disclosure of detailed information about business combination [Line Items]
Total consideration	50,368	1,816
Less: Fair value of identifiable net assets acquired	(83,482)	(3,009)
Goodwill	33,114	1,193
SER [Member]
Disclosure of detailed information about business combination [Line Items]
Total consideration	217,919	7,856
Less: Fair value of identifiable net assets acquired	$ (217,919)	$ (7,856)

Business Combinations - Summa_5

Business Combinations - Summary of Net Cash Outflow (Inflow) on Acquisition of Subsidiary (Detail) $ in Thousands, $ in Thousands	1 Months Ended	12 Months Ended
	Sep. 30, 2020TWD ($)	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2021USD ($)
Disclosure of detailed information about business combination [Line Items]
Net cash outflow (inflow) on acquisition of subsidiaries	$ 966,000
AMPI [member]
Disclosure of detailed information about business combination [Line Items]
Total consideration		$ 250,000
Less: Cash and cash equivalent acquired		(349,496)
Net cash outflow (inflow) on acquisition of subsidiaries		(99,496)
ASEEE [member]
Disclosure of detailed information about business combination [Line Items]
Total consideration		0
Less: Cash and cash equivalent acquired		(23,197)
Net cash outflow (inflow) on acquisition of subsidiaries		(23,197)
USIPL [member]
Disclosure of detailed information about business combination [Line Items]
Total consideration		313,057
Less: Cash and cash equivalent acquired		(108,718)
Net cash outflow (inflow) on acquisition of subsidiaries		204,339
FAFG [member]
Disclosure of detailed information about business combination [Line Items]
Total consideration		12,443,637
Total consideration		11,094,802
Less: Cash and cash equivalent acquired		(2,349,164)
Net cash outflow (inflow) on acquisition of subsidiaries		8,745,638
ITGEU
Disclosure of detailed information about business combination [Line Items]
Total consideration		50,368		$ 1,816
Less: Cash and cash equivalent acquired		(68,719)	$ (2,477)
Net cash outflow (inflow) on acquisition of subsidiaries		(18,351)	(661)
SER [Member]
Disclosure of detailed information about business combination [Line Items]
Total consideration		217,919		$ 7,856
Less: Cash and cash equivalent acquired		(18,850)	(680)
Net cash outflow (inflow) on acquisition of subsidiaries		$ 199,069	$ 7,176

Business Combinations - Summa_6

Business Combinations - Summary of Impact of Acquisitions by Comprehensive Income (Detail) $ in Thousands, $ in Thousands	1 Months Ended	2 Months Ended		8 Months Ended
	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2019TWD ($)	Dec. 31, 2019TWD ($)
AMPI [member]
Disclosure of detailed information about business combination [Line Items]
Operating revenue				$ 704,243
Net Profit (loss)				$ (217,163)
ASEEE [member]
Disclosure of detailed information about business combination [Line Items]
Operating revenue					$ 1,159
Net Profit (loss)					$ (469,598)
FAFG [member]
Disclosure of detailed information about business combination [Line Items]
Operating revenue	$ 2,043,440
Net Profit (loss)	$ 91,179
USIPL [member]
Disclosure of detailed information about business combination [Line Items]
Operating revenue		$ 39,080
Net Profit (loss)		(11,995)
ITGEU
Disclosure of detailed information about business combination [Line Items]
Operating revenue		75,221	$ 2,712
Net Profit (loss)		(4,593)	(166)
SER [Member]
Disclosure of detailed information about business combination [Line Items]
Operating revenue		225,017	8,112
Net Profit (loss)		$ (508)	$ (18)

Business Combinations - Summa_7

Business Combinations - Summary of Identification of the Difference Between the Cost of the Investment and the Group's Share of FAFG's Net Fair Value Of Identifiable Assets And Liabilities (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019TWD ($)	Dec. 31, 2018TWD ($)
Disclosure of transactions recognised separately from acquisition of assets and assumption of liabilities in business combination [line items]
Inventories	$ 67,832,981	$ 2,445,313	$ 48,590,434
Financial assets at fair value through profit or loss - non-current	2,502,834	90,225	2,180,978
Property, plant and equipment	239,867,550	8,646,992	234,365,397
Right-of-use assets	10,680,262	385,013	8,741,807
Goodwill	52,072,413	1,877,160	52,709,053	$ 1,900,110	$ 50,198,436	$ 49,974,446
Deferred tax liabilities	7,590,197	273,619	7,121,027
Non-controlling interests	$ 14,544,415	$ 524,312	15,622,009
After Retrospectively Adjusted [Member]
Disclosure of transactions recognised separately from acquisition of assets and assumption of liabilities in business combination [line items]
Inventories			48,590,434
Financial assets at fair value through profit or loss - non-current			2,180,978
Property, plant and equipment			234,365,397
Right-of-use assets			8,741,807
Goodwill			52,709,053
Other intangible assets			27,711,771
Deferred tax liabilities			7,121,027
Non-controlling interests			15,622,009
Before Retrospectively Adjusted [Member]
Disclosure of transactions recognised separately from acquisition of assets and assumption of liabilities in business combination [line items]
Inventories			48,516,459
Financial assets at fair value through profit or loss - non-current			1,793,188
Property, plant and equipment			233,207,324
Right-of-use assets			8,620,612
Goodwill			54,777,439
Other intangible assets			26,808,668
Deferred tax liabilities			6,551,233
Non-controlling interests			$ 15,616,053

Disposal of Subsidiaries - Summ

Disposal of Subsidiaries - Summary of Analysis of Assets and Liabilities on Date Control was Lost (Detail) - SPIL Cayman Holdings Limited [member] $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2021USD ($)
Current assets
Cash and cash equivalents	$ 2,625,715	$ 94,655	$ 200,347
Inventories	2,284,880	82,368	239,865
Other current assets	1,215,992	43,835	111,913
Trade and other receivables	4,505,531		318,425	$ 162,420
Non-Current Assets
Property, plant and equipment	16,693,129	601,770	7,546,413
Right-of-use assets	181,855	6,556	812,861
Investment property	787,250	28,379
Goodwill	310,711	11,201
Deferred tax assets	659,972	23,792	298,217
Other non-current assets	308,500	11,122	43,482
Current Liabilities
Short-term borrowings	(2,443,005)	(88,068)
Trade and other payables	(5,949,592)	(214,477)	(1,739,330)
Current portion of long-term borrowings			(1,746,000)
Other current liabilities	(647,027)	(23,325)	(24,564)
Non-Current Liabilities
Long-term borrowings			(2,947,682)
Deferred tax liabilities	(200,899)	(7,242)	(796)
Lease liabilities – non-current	(8,150)	(294)
Other non-current liabilities	(156,863)	(5,655)
Net assets disposed of	$ 20,167,999	$ 727,037	$ 3,113,151

Disposal of Subsidiaries - Su_2

Disposal of Subsidiaries - Summary of Gain on Disposal of Subsidiaries (Detail) $ in Thousands, $ in Thousands	1 Months Ended	12 Months Ended
	Sep. 30, 2020TWD ($)	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of gain from disposals of subsidiaries [line items]
Total consideration	$ 966,000
SPIL Cayman Holdings Limited [member]
Disclosure of gain from disposals of subsidiaries [line items]
Total consideration	$ 4,078,844	$ 36,939,133	$ 1,331,620	$ 4,078,844
Net assets disposed of		(20,167,999)	(727,037)	(3,113,151)
Reclassification of accumulated exchange difference from equity to profit or loss due to the loss of control		569,284	20,522	(162,940)
Gain on disposal of		$ 17,340,418	$ 625,105	$ 802,753

Disposal of Subsidiaries - Su_3

Disposal of Subsidiaries - Summary of Net Cash Inflow on Disposal of Susbsidiaries (Detail) $ in Thousands, $ in Thousands	1 Months Ended	12 Months Ended
	Sep. 30, 2020TWD ($)	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure Of Net Cash Inflow On Disposal Of Subsidiaries [Line Items]
Consideration received in cash and cash equivalents	$ 966,000
SPIL Cayman Holdings Limited [member]
Disclosure Of Net Cash Inflow On Disposal Of Subsidiaries [Line Items]
Consideration received in cash and cash equivalents	4,078,844	$ 36,939,133	$ 1,331,620	$ 4,078,844
Less: Cash and cash equivalent balances disposed of	(200,347)	(2,625,715)	(94,655)
Other receivables (the outstanding receivables of consideration, net of relevant expenditure)	(161,458)	(10,533,600)	(379,726)
Net cash inflow on disposals of subsidiaries	$ 3,717,039	$ 23,779,818	$ 857,239

Disposal of Subsidiaries - Addi

Disposal of Subsidiaries - Additional Information (Detail) - TWD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2021
Disposal of Subsidiaries [Line Items]
Total consideration	$ 966,000
Shenzhen Hiwin System Limited [Member]
Disposal of Subsidiaries [Line Items]
Percentage of Ownership (%)	100.00%
GAPT Holdings limited [Member]
Disposal of Subsidiaries [Line Items]
Percentage of Ownership (%)		100.00%

Equity Transaction with Non-c_2

Equity Transaction with Non-controlling Interests - Additional Information (Detail) $ / shares in Units, shares in Thousands, $ in Thousands, $ in Thousands	May 31, 2020USD ($)	Dec. 31, 2021TWD ($)shares	Sep. 30, 2020$ / shares	Jul. 31, 2019USD ($)$ / shares	Jul. 31, 2018TWD ($)$ / shares	Dec. 31, 2021TWD ($)$ / sharesshares	Dec. 31, 2019TWD ($)shares	Dec. 31, 2021USD ($)shares	Dec. 01, 2021TWD ($)	Dec. 01, 2021USD ($)	Sep. 30, 2021¥ / shares	Sep. 01, 2021TWD ($)	Sep. 01, 2021USD ($)	Dec. 31, 2020TWD ($)	Sep. 01, 2020TWD ($)shares	Jul. 31, 2019TWD ($)	Jul. 01, 2019TWD ($)shares
USI Enterprise Limited ("USIE") [member]
Increase (decrease) in capital surplus		$ 2,093,787				$ 2,093,787		$ 75,479	$ 47,171	$ 1,700				$ 2,760,175	$ 780,533		$ 1,625,448
Number of shares approved for repurchase | shares		9,137				9,137		9,137							10,308		7,378
Shares repurchase price per share | $ / shares			$ 19.47	$ 14.30		$ 17.20
USI Enterprise Limited ("USIE") [member] | Bottom of range [member]
Percentage of increase in shareholdings		95.85%	95.00%	95.42%
USI Enterprise Limited ("USIE") [member] | Top of range [member]
Percentage of increase in shareholdings		100.00%	99.62%	98.72%
ASEN [member]
Increase (decrease) in capital surplus																$ 2,650,950
Amount of shares transferred																$ 97,748
Percentage of shareholdings				30.00%
Amount of shareholdings				$ 162,870
ASEN [member] | Bottom of range [member]
Percentage of increase in ownership				70.00%
ASEN [member] | Top of range [member]
Percentage of increase in ownership				100.00%
USI INC [member]
Increase (decrease) in capital surplus					$ 142
Ordinary shares outstanding acquired price | $ / shares					$ 18
USISH [Member]
Increase (decrease) in capital surplus		$ 436,927				$ 436,927	$ 334,719	$ 15,751				$ 11,277	$ 407
Number of shares approved for repurchase | shares		16,042				16,042	13,037	16,042
USISH [Member] | Bottom of range [member]
Percentage of increase in shareholdings							74.60%
Par value per share | ¥ / shares											¥ 13.86
USISH [Member] | Top of range [member]
Percentage of increase in shareholdings							77.70%
Par value per share | ¥ / shares											¥ 14.95
ASEEE [member]
Increase (decrease) in capital surplus																	$ 128,805
Percentage of ShareHolding Held				100.00%
USIPL [Member]
Increase (decrease) in capital surplus														$ 13,502
Amount of shareholdings	$ 24,500
Percentage of shareholdings	40.00%
USIPL [Member] | Bottom of range [member]
Percentage of increase in ownership	60.00%
USIPL [Member] | Top of range [member]
Percentage of increase in ownership	100.00%

Cash Flows Information - Summar

Cash Flows Information - Summary of Non-cash Investing Activities (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Payments for property, plant and equipment
Purchase of property, plant and equipment	$ 74,417,541	$ 2,682,681	$ 59,024,201	$ 63,073,887
Increase in other non-current assets	1,184,927	42,715	78,291	68,560
Decrease (increase) in other payables	(4,671,228)	(168,394)	3,029,162	(6,254,579)
Capitalized borrowing costs	(25,581)	(922)	(54,208)	(77,715)
Payments for property, plant and equipment	70,905,659	2,556,080	62,077,446	56,810,153
Proceeds from disposal of property, plant and equipment
Consideration from disposal of property, plant and equipment	1,128,850	40,693	5,184,925	441,444
Increase in other non-current assets	(134,760)	(4,858)
Increase (decrease) in other receivables	610,912	22,024	(735,812)	7,495
Proceeds from disposal of property, plant and equipment	1,605,002	57,859	4,449,113	448,939
Payments for other intangible assets
Purchase of other intangible assets	1,069,866	38,568	982,655	1,350,908
Decrease in other payables				60,160
Purchase of intangible assets classified as investing activities	$ 1,069,866	$ 38,568	$ 982,655	$ 1,411,068

Cash Flows Information - Change

Cash Flows Information - Change in Liabilities Arising From Financing Activities (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021USD ($)	Dec. 31, 2021TWD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of non-cash investing activities [line items]
Beginning balance	$ 7,538,500	$ 209,117,966	$ 223,982,006	$ 208,132,097
Net financing cash flows	772,739	21,435,763	(9,129,670)	15,104,066
Interest under operating activities	29	800	111	1,766
Rent expense under operating activities	(7)	(184)	(7,729)
Convertible bonds classified separately as equity components and embedded derivative liability	(14,418)	(399,955)
Non-cash changes
Lease liabilities	73,456	2,037,665	584,642	536,216
Amortization of issuance cost	12,663	351,262	171,232	200,673
Convertible bonds issued by subsidiaries and converted to ordinary shares	(4)	(102)
Lease modifications	(2,120)	(58,799)	(289,687)	(239,321)
Adjustments for government subsidy			41,650
Acquisition of subsidiaries (Note 29)	6,516	180,745	990,023	2,508,101
Disposal of subsidiaries (Note 30)	(89,245)	(2,475,660)	(4,694,352)
Reclassification	13,709	380,292
Effects of foreign currency exchange	(122,338)	(3,393,653)	(2,530,260)	(2,261,592)
Ending balance	8,189,480	227,176,140	209,117,966	223,982,006
Short-term borrowings [member]
Disclosure of non-cash investing activities [line items]
Beginning balance	1,247,219	34,597,858	40,572,329	47,163,103
Net financing cash flows	362,055	10,043,398	(1,502,323)	(4,683,142)
Non-cash changes
Short-term borrowings transferred to long-term borrowings			(3,850,000)	(1,499,000)
Acquisition of subsidiaries (Note 29)			356,417	656,820
Disposal of subsidiaries (Note 30)	(88,068)	(2,443,005)
Effects of foreign currency exchange	(41,883)	(1,161,822)	(978,565)	(1,065,452)
Ending balance	1,479,323	41,036,429	34,597,858	40,572,329
Bonds payable [member]
Disclosure of non-cash investing activities [line items]
Beginning balance	2,027,886	56,253,554	36,522,155	16,985,936
Net financing cash flows	(134,068)	(3,719,057)	19,717,149	19,279,033
Convertible bonds classified separately as equity components and embedded derivative liability	(14,418)	(399,955)
Non-cash changes
Amortization of issuance cost	4,553	126,283	14,250	11,522
Convertible bonds issued by subsidiaries and converted to ordinary shares	(4)	(102)
Acquisition of subsidiaries (Note 29)				245,664
Effects of foreign currency exchange	238	6,614
Ending balance	1,884,187	52,267,337	56,253,554	36,522,155
Long-term borrowings [member]
Disclosure of non-cash investing activities [line items]
Beginning balance	4,051,577	112,390,724	141,078,598	137,898,329
Net financing cash flows	577,463	16,018,825	(26,500,139)	1,144,731
Non-cash changes
Amortization of issuance cost	8,110	224,979	156,982	189,151
Short-term borrowings transferred to long-term borrowings			3,850,000	1,499,000
Adjustments for government subsidy			41,650
Acquisition of subsidiaries (Note 29)				1,523,968
Disposal of subsidiaries (Note 30)			(4,693,682)
Effects of foreign currency exchange	(77,939)	(2,162,038)	(1,542,685)	(1,176,581)
Ending balance	4,559,211	126,472,490	112,390,724	141,078,598
Lease liabilities [member]
Disclosure of non-cash investing activities [line items]
Beginning balance	211,818	5,875,830	5,808,924	6,084,729
Net financing cash flows	(32,711)	(907,403)	(844,357)	(636,556)
Interest under operating activities	29	800	111	1,766
Rent expense under operating activities	(7)	(184)	(7,729)
Non-cash changes
Lease liabilities	73,456	2,037,665	584,642	536,216
Lease modifications	(2,120)	(58,799)	(289,687)	(239,321)
Acquisition of subsidiaries (Note 29)	6,516	180,745	633,606	81,649
Disposal of subsidiaries (Note 30)	(1,177)	(32,655)	(670)
Reclassification	13,709	380,292
Effects of foreign currency exchange	(2,754)	(76,407)	(9,010)	(19,559)
Ending balance	$ 266,759	$ 7,399,884	$ 5,875,830	$ 5,808,924

Financial Instruments - Summary

Financial Instruments - Summary of Fair Value of Financial Instruments Not Measured at Fair Value but for Which Fair Value is Disclosed (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of detailed information about financial instruments [line items]
Bonds payable	$ 52,267,337	$ 1,884,187	$ 56,253,554
Fair value [member]
Disclosure of detailed information about financial instruments [line items]
Bonds payable	$ 52,429,758	$ 1,890,042	$ 56,448,769

Financial Instruments - Summa_2

Financial Instruments - Summary of Fair Value of Financial Instruments that are Measured at Fair Value on a Recurring Basis (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			$ 6,523,583
Financial assets mandatorily classified as at FVTPL	$ 5,436,280	$ 195,973	6,523,583
Financial assets at FVTOCI	8,112,274	292,439	2,367,547
Financial liabilities at FVTPL	417,660	15,056	1,537,208
Trade receivables, net	1,076,458	38,805	1,012,736
Swap contracts [member] | Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			99,312
Financial assets mandatorily classified as at FVTPL	85,629	3,087	99,312
Financial liabilities at FVTPL	360,797	13,006	1,448,972
Forward exchange contracts [member] | Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			122,511
Financial assets mandatorily classified as at FVTPL	23,373	843	122,511
Financial liabilities at FVTPL	56,863	2,050	9,020
Quoted ordinary shares [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets at FVTOCI, Investments in equity instruments	102,124	3,682
Quoted ordinary shares [member] | Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			4,064,438
Financial assets mandatorily classified as at FVTPL	2,683,193	96,726	4,064,438
Open-end mutual funds [member] | Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			339,338
Financial assets mandatorily classified as at FVTPL	334,223	12,049	339,338
Unquoted preferred shares [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets at FVTOCI, Investments in equity instruments	11,245	405	151,329
Unquoted preferred shares [member] | Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			385,440
Financial assets mandatorily classified as at FVTPL	583,270	21,026	385,440
Private-placement funds [member] | Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			1,124,754
Financial assets mandatorily classified as at FVTPL	1,322,686	47,682	1,124,754
Contingent considerations [member] | Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			387,790
Financial assets mandatorily classified as at FVTPL	394,943	14,237	387,790
Unquoted ordinary shares [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets at FVTOCI, Investments in equity instruments	820,779	29,588	567,377
Limited partnership [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets at FVTOCI, Investments in equity instruments	9,206	332	9,692
Unsecured subordinate corporate bonds [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets at FVTOCI, Investments in debt instruments	1,076,458	38,805	1,012,736
Trade receivables, net	6,092,462	219,627	626,413
Forward exchange contracts [member] | Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial liabilities at FVTPL	56,863	2,050
Target redemption forward contracts [member] | Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	500	18
Financial liabilities at FVTPL			79,216
Redemption option and put option of convertible bonds [member] | Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	8,463	305
Level 1 of fair value hierarchy [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			4,403,776
Financial assets mandatorily classified as at FVTPL	3,017,416	108,775
Financial assets at FVTOCI	102,124	3,682
Level 1 of fair value hierarchy [member] | Quoted ordinary shares [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets at FVTOCI, Investments in equity instruments	102,124	3,682
Level 1 of fair value hierarchy [member] | Quoted ordinary shares [member] | Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			4,064,438
Financial assets mandatorily classified as at FVTPL	2,683,193	96,726
Level 1 of fair value hierarchy [member] | Open-end mutual funds [member] | Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			339,338
Financial assets mandatorily classified as at FVTPL	334,223	12,049
Level 2 of fair value hierarchy [Member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			221,823
Financial assets mandatorily classified as at FVTPL	117,965	4,253
Financial liabilities at FVTPL	417,660	15,056	1,537,208
Level 2 of fair value hierarchy [Member] | Swap contracts [member] | Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			99,312
Financial assets mandatorily classified as at FVTPL	85,629	3,087
Financial liabilities at FVTPL	360,797	13,006	1,448,972
Level 2 of fair value hierarchy [Member] | Forward exchange contracts [member] | Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			122,511
Financial assets mandatorily classified as at FVTPL	23,373	843
Financial liabilities at FVTPL			9,020
Level 2 of fair value hierarchy [Member] | Forward exchange contracts [member] | Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial liabilities at FVTPL	56,863	2,050
Level 2 of fair value hierarchy [Member] | Target redemption forward contracts [member] | Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	500	18
Financial liabilities at FVTPL			79,216
Level 2 of fair value hierarchy [Member] | Redemption option and put option of convertible bonds [member] | Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	8,463	305
Level 3 of fair value hierarchy [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			1,897,984
Financial assets mandatorily classified as at FVTPL	2,300,899	82,945
Financial assets at FVTOCI	8,010,150	288,757	2,367,547
Level 3 of fair value hierarchy [member] | Unquoted preferred shares [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets at FVTOCI, Investments in equity instruments	11,245	405	151,329
Level 3 of fair value hierarchy [member] | Unquoted preferred shares [member] | Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			385,440
Financial assets mandatorily classified as at FVTPL	583,270	21,026
Level 3 of fair value hierarchy [member] | Private-placement funds [member] | Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			1,124,754
Financial assets mandatorily classified as at FVTPL	1,322,686	47,682
Level 3 of fair value hierarchy [member] | Contingent considerations [member] | Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			387,790
Financial assets mandatorily classified as at FVTPL	394,943	14,237
Level 3 of fair value hierarchy [member] | Unquoted ordinary shares [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets at FVTOCI, Investments in equity instruments	820,779	29,588	567,377
Level 3 of fair value hierarchy [member] | Limited partnership [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets at FVTOCI, Investments in equity instruments	9,206	332	9,692
Level 3 of fair value hierarchy [member] | Unsecured subordinate corporate bonds [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets at FVTOCI, Investments in debt instruments	1,076,458	38,805	1,012,736
Trade receivables, net	$ 6,092,462	$ 219,627	$ 626,413

Financial Instruments - Additio

Financial Instruments - Additional Information (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019TWD ($)	Dec. 31, 2018TWD ($)	Dec. 31, 2021USD ($)
Disclosure of detailed information about financial instruments [line items]
Significant unobservable inputs discount rate	31.00%	31.00%
Increase percentage of significant unobservable inputs discount rate	1.00%	1.00%	0.10%	0.10%
Fair value of unquoted shares decreased	$ 19,300		$ 9,700				$ 696
Fair value of bonds decreased	$ 4,000	$ 144	$ 5,000
Percentage of trade receivables	33.00%		27.00%				33.00%
Bottom of range [member] | Actuarial assumption of discount rates [member]
Disclosure of detailed information about financial instruments [line items]
Significant unobservable inputs discount rate	10.00%	10.00%
Top of range [member] | Actuarial assumption of discount rates [member]
Disclosure of detailed information about financial instruments [line items]
Significant unobservable inputs discount rate	30.00%	30.00%
Floating interest rate [member]
Disclosure of detailed information about financial instruments [line items]
Increase decrease in profit before tax			$ 959,000	$ 34,571	$ 862,000	$ 1,232,000
Currency risk [member]
Disclosure of detailed information about financial instruments [line items]
Value at risk	$ 38,000		35,000		82,000		$ 1,370
Other price risk [member]
Disclosure of detailed information about financial instruments [line items]
Increase decrease in profit before tax	49,000	$ 1,766	59,000		$ 51,000
Equity debt ratio					1.00%
Increase decrease in other comprehensive income	$ 9,000	$ 324	$ 7,000		$ 8,000

Financial Instruments - Summa_3

Financial Instruments - Summary of Financial Assets Measured at Level 3 Fair Value (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of fair value measurement of assets [line items]
Beginning Balance	$ 584,152,644
Net increase in trade receivables	(27,957,812)	$ (1,007,852)	$ (9,396,304)	$ 995,839
Exercise of call option	(2,727,915)	(98,339)	(1,934,530)	(1,149,227)
Ending Balance	673,265,899	24,270,582	584,152,644
Available-for-sale [member] | Level 3 of fair value hierarchy [member]
Disclosure of fair value measurement of assets [line items]
Beginning Balance	4,265,531	153,767	4,806,179	2,072,446
Recognized in profit or loss	131,276	4,732	(17,941)	3,431
Recognized in other comprehensive income (included in unrealized losses on financial assets at FVTOCI)	193,448	6,974	(151,992)	(218,173)
Recognized in other comprehensive income (effects of foreign currency exchange)	(84,122)	(3,033)	(31,017)	(20,063)
Net increase in trade receivables	18,210,321	656,464	6,005,816	3,171,205
Trade receivables factoring (purchases)	(12,744,272)	(459,418)	(7,409,093)	(1,141,515)
Purchases	491,292	17,711	1,152,402	951,513
Disposals	(122,666)	(4,422)	(450,625)	(12,665)
Exercise of call option			(25,988)
Reclassify	(29,758)	(1,073)
Acquisition through business combinations			387,790
Ending Balance	10,311,050	371,702	4,265,531	4,806,179
Available-for-sale [member] | Level 3 of fair value hierarchy [member] | Adjusted [Member]
Disclosure of fair value measurement of assets [line items]
Beginning Balance	4,265,531
Ending Balance			4,265,531
Available-for-sale [member] | Level 3 of fair value hierarchy [member] | FVTPL equity instrument [member]
Disclosure of fair value measurement of assets [line items]
Beginning Balance	1,897,984	68,421	1,005,714	475,123
Recognized in profit or loss	131,276	4,732	(17,941)	3,431
Recognized in other comprehensive income (effects of foreign currency exchange)	(79,614)	(2,870)	(15,455)	(14,368)
Purchases	459,046	16,548	893,234	541,528
Disposals	(107,793)	(3,886)	(329,370)
Exercise of call option			(25,988)
Acquisition through business combinations			387,790
Ending Balance	2,300,899	82,945	1,897,984	1,005,714
Available-for-sale [member] | Level 3 of fair value hierarchy [member] | FVTPL equity instrument [member] | Adjusted [Member]
Disclosure of fair value measurement of assets [line items]
Beginning Balance	1,897,984
Ending Balance			1,897,984
Available-for-sale [member] | Level 3 of fair value hierarchy [member] | FVTPL debt instrument [member]
Disclosure of fair value measurement of assets [line items]
Beginning Balance	0	0	0
Net increase in trade receivables	3,269,782	117,872	370,110
Trade receivables factoring (purchases)	(3,269,782)	(117,872)	(370,110)
Ending Balance	0	0	0	0
Available-for-sale [member] | Level 3 of fair value hierarchy [member] | FVOCI equity instruments [member]
Disclosure of fair value measurement of assets [line items]
Beginning Balance	728,398	26,257	755,903	580,399
Recognized in other comprehensive income (included in unrealized losses on financial assets at FVTOCI)	129,726	4,677	(149,856)	(216,121)
Recognized in other comprehensive income (effects of foreign currency exchange)	(4,508)	(163)	(15,562)	(5,695)
Purchases	32,246	1,163	259,168	409,985
Disposals	(14,873)	(536)	(121,255)	(12,665)
Reclassify	(29,758)	(1,073)
Ending Balance	841,231	30,325	728,398	755,903
Available-for-sale [member] | Level 3 of fair value hierarchy [member] | FVOCI debt instruments [member]
Disclosure of fair value measurement of assets [line items]
Beginning Balance	1,639,149	59,089	3,044,562	1,016,924
Recognized in other comprehensive income (included in unrealized losses on financial assets at FVTOCI)	63,722	2,297	(2,136)	(2,052)
Net increase in trade receivables	14,940,539	538,592	5,635,706	3,171,205
Trade receivables factoring (purchases)	(9,474,490)	(341,546)	(7,038,983)	(1,141,515)
Ending Balance	$ 7,168,920	$ 258,432	$ 1,639,149	$ 3,044,562

Financial Instruments - Summa_4

Financial Instruments - Summary of Categories of Financial Instruments (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of detailed information about financial instruments [line items]
Mandatorily at FVTPL	$ 5,436,280	$ 195,973	$ 6,523,583
Measured at amortized cost (Note 1)	200,732,680	7,236,218	147,521,583
Trade receivables, net	115,462,210	4,162,300	91,833,989
Held for trading	417,660	15,056	1,537,208
Financial liabilities for hedging	11,497,896	414,488	11,188,244
Measured at amortized cost (Note 2)	339,445,544	12,236,683	304,737,749
Financial assets at fair value through other comprehensive income, category [member]
Disclosure of detailed information about financial instruments [line items]
Equity instruments	943,354	34,007	728,398
Debt instruments	1,076,458	38,805	1,012,736
Trade receivables, net	$ 6,092,462	$ 219,627	$ 626,413

Financial Instruments - Summa_5

Financial Instruments - Summary of Detailed Information About Hedges (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Disclosure of detailed information about hedges [line items]
Financial liabilities for hedging – current	$ 6,716,965	$ 242,140	$ 5,277,325
Fair value hedge of borrowings denominated in foreign currencies [member]
Disclosure of detailed information about hedges [line items]
Financial liabilities for hedging – current	2,954,921	106,522	3,307,018
Current Financial Assets For Hedging – current	0	0	0
Hedges of net investment in foreign operations [member]
Disclosure of detailed information about hedges [line items]
Financial liabilities for hedging – current	3,762,044	135,618	1,970,307
Financial liabilities for hedging – non-current	4,780,931	172,348	5,910,919
Current Financial Assets For Hedging – current	0	0	0
Non Current Financial Assets For Hedging – non-current	$ 0	$ 0	$ 0

Financial Instruments - Summa_6

Financial Instruments - Summary of Detailed Information About Hedges Items (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2021USD ($)
Borrowings denominated in foreign currencies [member]
Disclosure of detailed information about hedged items [line items]
Hedged item, assets	$ 2,318,517		$ 2,859,132	$ 83,580
Fair value hedge of borrowings denominated in foreign currencies [member]
Disclosure of detailed information about hedged items [line items]
Change in Value Used for Calculating Hedge Ineffectiveness, Hedging Instrument	94,145	$ 3,394	157,842
Hedged item, assets	(94,145)		(157,842)	(3,394)
Accumulated Amount of Fair Value Hedge Adjustments on Hedged Item, Asset	(236,362)		(142,217)	(8,521)
Hedges of net investment in foreign operations [member]
Disclosure of detailed information about hedged items [line items]
Change in Value Used for Calculating Hedge Ineffectiveness, Hedging Instrument	(738,600)	$ (26,626)	574,824
Hedged item, assets	738,600		(574,824)	26,626
Accumulated Gains or Losses in Other Equity, Continuing Hedges	$ 163,776		$ (574,824)	$ 5,904

Financial Instruments - Summa_7

Financial Instruments - Summary of Interest Rate Risk (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Fair value interest rate risk [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets	$ 5,474,105	$ 197,336	$ 5,049,005
Financial liabilities	76,206,394	2,747,166	56,599,417
Cash flow interest rate risk [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets	69,654,969	2,510,994	45,489,788
Financial liabilities	$ 158,557,225	$ 5,715,834	$ 131,715,366

Financial Instruments - Summa_8

Financial Instruments - Summary of Maturity Analysis for Non-derivative Financial Liabilities (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Less than 1 month [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	$ 75,266,483	$ 2,713,283	$ 68,903,001
Less than 1 month [member] | Obligation under leases [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	84,978	3,063	103,734
Less than 1 month [member] | Non interest bearing [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	52,353,176	1,887,281	43,111,390
Less than 1 month [member] | Floating interest rate [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	12,565,548	452,976	13,792,596
Less than 1 month [member] | Fixed interest rate [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	10,262,781	369,963	11,895,281
1 to 3 months [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	56,572,557	2,039,386	52,992,946
1 to 3 months [member] | Obligation under leases [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	157,710	5,685	151,921
1 to 3 months [member] | Non interest bearing [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	48,140,652	1,735,424	44,122,659
1 to 3 months [member] | Floating interest rate [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	5,180,527	186,753	8,190,076
1 to 3 months [member] | Fixed interest rate [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	3,093,668	111,524	528,290
3 months to 1 year [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	37,298,883	1,344,589	22,407,360
3 months to 1 year [member] | Obligation under leases [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	687,144	24,771	619,908
3 months to 1 year [member] | Non interest bearing [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	10,216,253	368,286	8,223,684
3 months to 1 year [member] | Floating interest rate [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	13,416,893	483,666	10,214,154
3 months to 1 year [member] | Fixed interest rate [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	12,978,593	467,866	3,349,614
1-5 years [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	158,925,804	5,729,121	151,252,482
1-5 years [member] | Obligation under leases [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	2,585,624	93,209	1,779,041
1-5 years [member] | Non interest bearing [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	291,480	10,508	319,510
1-5 years [member] | Floating interest rate [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	112,493,242	4,055,272	102,253,481
1-5 years [member] | Fixed interest rate [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	43,555,458	1,570,132	46,900,450
More than 5 years [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	18,018,340	649,544	17,895,489
More than 5 years [member] | Obligation under leases [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	4,929,602	177,707	4,088,301
More than 5 years [member] | Non interest bearing [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	114,201	4,117	176,536
More than 5 years [member] | Floating interest rate [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	7,494,670	270,176	7,999,130
More than 5 years [member] | Fixed interest rate [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	$ 5,479,867	$ 197,544	$ 5,631,522

Financial Instruments - Summa_9

Financial Instruments - Summary of Detailed Information about Maturity Analysis of Obligation under Leases (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Less than 1 year [member] | Obligation under leases [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	$ 929,832	$ 33,519	$ 875,563
1-5 years [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	158,925,804	5,729,121	151,252,482
1-5 years [member] | Obligation under leases [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	2,585,624	93,209	1,779,041
5 to 10 Years [member] | Obligation under leases [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	1,731,995	62,437	1,422,331
10 to 15 Years [member] | Obligation under leases [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	883,335	31,843	776,735
15 to 20 Years [member] | Obligation under leases [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	802,765	28,939	674,446
More than 20 Years [member] | Obligation under leases [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Non-derivative financial liabilities undiscounted amounts	$ 1,511,507	$ 54,488	$ 1,214,789

Financial Instruments - Summ_10

Financial Instruments - Summary of Maturity Analysis for Derivative Financial Instruments (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Less than 1 month [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	$ (52,779)	$ (1,903)	$ (150,128)
Less than 1 month [member] | Forward exchange contracts [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Net settled	(21,379)	(771)	30,514
Gross settled	1,956	70	64,444
Less than 1 month [member] | Forward exchange contracts [member] | Inflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	2,382,315	85,880	8,862,682
Less than 1 month [member] | Forward exchange contracts [member] | Outflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	(2,380,359)	(85,810)	(8,798,238)
Less than 1 month [member] | Swap contracts [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	(55,266)	(1,992)	(212,821)
Less than 1 month [member] | Swap contracts [member] | Inflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	23,759,435	856,505	19,311,999
Less than 1 month [member] | Swap contracts [member] | Outflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	(23,814,701)	(858,497)	(19,524,820)
Less than 1 month [member] | Target redemption forward contracts [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	531	19	(1,751)
Less than 1 month [member] | Target redemption forward contracts [member] | Inflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	19,376	698	42,720
Less than 1 month [member] | Target redemption forward contracts [member] | Outflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	(18,845)	(679)	(44,471)
1 to 3 months [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	(8,075)	(291)	(264,082)
1 to 3 months [member] | Forward exchange contracts [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Net settled	(1,410)	(51)	18,429
Gross settled	32,722	1,180	46,984
1 to 3 months [member] | Forward exchange contracts [member] | Inflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	6,817,411	245,761	5,565,137
1 to 3 months [member] | Forward exchange contracts [member] | Outflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	(6,784,689)	(244,581)	(5,518,153)
1 to 3 months [member] | Swap contracts [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	(41,992)	(1,514)	(307,126)
1 to 3 months [member] | Swap contracts [member] | Inflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	21,272,450	766,851	17,179,871
1 to 3 months [member] | Swap contracts [member] | Outflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	(21,314,442)	(768,365)	(17,486,997)
1 to 3 months [member] | Target redemption forward contracts [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	1,195	43	(3,940)
1 to 3 months [member] | Target redemption forward contracts [member] | Inflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	43,596	1,572	96,120
1 to 3 months [member] | Target redemption forward contracts [member] | Outflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	(42,401)	(1,529)	(100,060)
3 months to 1 year [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	(116,984)	(4,217)	(768,591)
3 months to 1 year [member] | Forward exchange contracts [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Net settled	0	0
Gross settled	5,676	205	4,456
3 months to 1 year [member] | Forward exchange contracts [member] | Inflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	531,596	19,164	531,336
3 months to 1 year [member] | Forward exchange contracts [member] | Outflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	(525,920)	(18,959)	(526,880)
3 months to 1 year [member] | Swap contracts [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	(123,633)	(4,457)	(755,972)
3 months to 1 year [member] | Swap contracts [member] | Inflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	37,841,805	1,364,160	36,739,200
3 months to 1 year [member] | Swap contracts [member] | Outflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	(37,965,438)	(1,368,617)	(37,495,172)
3 months to 1 year [member] | Target redemption forward contracts [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	973	35	(17,075)
3 months to 1 year [member] | Target redemption forward contracts [member] | Inflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	33,216	1,197	416,520
3 months to 1 year [member] | Target redemption forward contracts [member] | Outflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled	$ (32,243)	$ (1,162)	(433,595)
More than 1 year [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled			(8,953)
More than 1 year [member] | Target redemption forward contracts [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled			(8,953)
More than 1 year [member] | Target redemption forward contracts [member] | Inflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled			227,128
More than 1 year [member] | Target redemption forward contracts [member] | Outflows [member]
Disclosure of maturity analysis for derivative financial liabilities [line items]
Gross settled			$ (236,081)

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) $ in Thousands, $ in Thousands	1 Months Ended
	Dec. 31, 2021TWD ($)shares	Dec. 31, 2021USD ($)shares	Sep. 30, 2020TWD ($)shares	Jul. 31, 2019TWD ($)shares	Sep. 30, 2021TWD ($)	Sep. 30, 2021USD ($)	Dec. 31, 2019TWD ($)
Associates [member]
Disclosure of transactions between related parties [line items]
Real estate properties acquired | $							$ 2,326,000
HC associates [Member]
Disclosure of transactions between related parties [line items]
Real estate properties acquired					$ 2,362,000	$ 85,148
USI Enterprise Limited ("USIE") [member]
Disclosure of transactions between related parties [line items]
Repurchase of outstanding ordinary shares | shares | shares	2,271	2,271	2,685	2,805
Value of ordinary shares purchased	$ 1,081,214	$ 38,977	$ 1,520,976	$ 1,247,187

Related Party Transactions - Su

Related Party Transactions - Summary of Transactions Between Related Parties (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of transactions between related parties [line items]
Amount contributed related party transactions	$ 110,000	$ 3,965	$ 100,000	$ 100,000
ASE Cultural and Educational Foundation [member]
Disclosure of transactions between related parties [line items]
Amount contributed related party transactions	10,000	360		100,000
ASE Environmental Protection And Sustainability Foundation [Member]
Disclosure of transactions between related parties [line items]
Amount contributed related party transactions	$ 100,000	$ 3,605	$ 100,000	$ 0

Related Party Transactions - _2

Related Party Transactions - Summary of Compensation to Key Management Personnel (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of transactions between related parties [abstract]
Short-term employee benefits	$ 1,744,903	$ 62,902	$ 1,264,980	$ 1,027,191
Post-employment benefits	3,505	126	2,007	2,208
Share-based payments	163,697	5,901	153,774	134,544
Total	$ 1,912,105	$ 68,929	$ 1,420,761	$ 1,163,943

Assets Pledged as Collateral _3

Assets Pledged as Collateral or for Security - Summary of Assets Pledged as Collateral or for Security (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)
Assets Pledged As Collateral or For Security [abstract]
Inventories related to real estate business	$ 2,587,110	$ 93,263	$ 10,564,873
Property, plant and equipment	114,390	4,124	124,124
Investment properties	20,796,862	749,707	11,847,145
Other financial assets (including current and non-current)	444,358	16,018	460,890
Total	$ 23,942,720	$ 863,112	$ 22,997,032

Assets Pledged as Collateral _4

Assets Pledged as Collateral or for Security - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2020
FAFG [Member] | Syndicated bank loans [Member]
Disclosure of detailed information about business combination [line items]
Proportion of Ownership Interest in Subsidiary Pledged as Collateral	89.60%

Significant Contingent Liabil_2

Significant Contingent Liabilities and Unrecognized Commitments - Additional Information (Detail) $ in Thousands, $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)	Dec. 31, 2021USD ($)
Disclosure of contingent liabilities [line items]
Unused letters of credit		$ 74,000		$ 2,000		$ 2,668
Committed to purchase property, plant and equipment		52,678,554		32,627,411		1,899,011
Prepayment of property, plant and equipment		3,761,120	$ 135,585	1,968,779
Construction contract related to real estate business		59	2	602,548
Letter of credits		738,628		671,721		26,627
Approved contribution in consideration of corporate social responsibility for environmental protection		100,000				3,605
Amount contributed related party transactions		110,000	3,965	100,000	$ 100,000
ASE Environmental Protection And Sustainability Foundation [Member]
Disclosure of contingent liabilities [line items]
Amount contributed related party transactions		100,000	3,605	$ 100,000	$ 0
ASE Cultural and Educational Foundation [Member]
Disclosure of contingent liabilities [line items]
Amount contributed related party transactions		20,000	$ 721
Taiwan [member]
Disclosure of contingent liabilities [line items]
Contractual period for environmental protection	30 years
Contribution to be made for environmental protection		$ 3,000,000				$ 108,147

Others - Additional Information

Others - Additional Information (Detail) ¥ in Thousands, $ in Thousands	Dec. 27, 2020TWD ($)	Jun. 30, 2020CNY (¥)	Feb. 10, 2020TWD ($)	Dec. 31, 2013TWD ($)
Disclosure Detailed Information About Others [Line Items]
Contribution received from Environmental Protection	$ 55,062
Procuratorate [Member]
Disclosure Detailed Information About Others [Line Items]
Administrative fine imposed | ¥		¥ 400
Income from fines and penalties | ¥		¥ 344
Original Fine [Member]
Disclosure Detailed Information About Others [Line Items]
Administrative fine imposed				$ 102,014
New Fine [Member]
Disclosure Detailed Information About Others [Line Items]
Administrative fine imposed			$ 46,952

Significant Assets and Liabil_3

Significant Assets and Liabilities Denominated in Foreign Currencies - Summary of Significant Assets and Liabilities Denominated in Foreign Currencies (Detail) € in Thousands, ¥ in Thousands, ¥ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands

12 Months Ended

Dec. 31, 2021TWD ($)

Dec. 31, 2020TWD ($)

Dec. 31, 2019

Dec. 31, 2021USD ($)

Dec. 31, 2021CNY (¥)

Dec. 31, 2021EUR (€)

Dec. 31, 2021JPY (¥)

Dec. 31, 2020USD ($)

Dec. 31, 2020CNY (¥)

Dec. 31, 2020EUR (€)

Dec. 31, 2020JPY (¥)

Dec. 31, 2020HKD ($)

US Dollar [member] | US dollar equals to New Taiwan dollar [member]

Disclosure of detailed information about financial instruments [line items]

Financial assets

$ 135,221,324

$ 121,583,265

$ 4,885,163

$ 4,269,075

Financial liabilities

$ 135,621,853

$ 126,448,786

4,899,633

4,439,915

Exchange Rate

US$1=NT$27.68

US$1=NT$28.48

US$1=NT$29.98

Exchange Rate

US$1=NT$27.68

US$1=NT$28.48

US$1=NT$29.98

US Dollar [member] | US dollar equals to Chinese yuan [member]

Disclosure of detailed information about financial instruments [line items]

Financial assets

1,718,314

¥ 47,562,940

1,527,381

¥ 43,499,803

Financial liabilities

1,503,606

¥ 41,619,803

1,517,568

¥ 43,220,325

Exchange Rate

US$1=RMB6.3757

US$1=RMB6.5249

Exchange Rate

US$1=RMB6.3757

US$1=RMB6.5249

US Dollar [member] | Us Dollar Equals To Euro [Member]

Disclosure of detailed information about financial instruments [line items]

Financial assets

42,250

€ 1,169,492

41,643

€ 1,185,984

Financial liabilities

88,741

€ 2,456,363

20,896

€ 595,128

Exchange Rate

US$1=EUR0.8829

US$1=EUR0.8143

Exchange Rate

US$1=EUR0.8829

US$1=EUR0.8143

Japanese Yen [Member] | Japanese yen equals to New Taiwan dollar [member]

Disclosure of detailed information about financial instruments [line items]

Financial assets

$ 3,026,677

$ 3,742,306

¥ 12,584,942

¥ 13,544,360

Financial liabilities

$ 3,385,776

$ 3,773,695

14,078,075

13,657,967

Exchange Rate

JPY1=NT$0.2405

JPY1=NT$0.2763

Exchange Rate

JPY1=NT$0.2405

JPY1=NT$0.2763

Japanese Yen [Member] | Japanese yen equals to US dollar [member]

Disclosure of detailed information about financial instruments [line items]

Financial assets

132,635

551,496

324,434

1,174,208

Financial liabilities

$ 238,255

¥ 990,667

$ 328,424

¥ 1,188,650

Exchange Rate

JPY1=US$0.0087

JPY1=US$0.0097

Exchange Rate

JPY1=US$0.0087

JPY1=US$0.0097

Hong Kong, Dollars | HK dollar equal to New Taiwan dollar [member]

Disclosure of detailed information about financial instruments [line items]

Financial assets

$ 641,912

$ 174,765

Financial liabilities

$ 69,103

$ 18,814

Exchange Rate

HKD1=NT$3.6730

Exchange Rate

HKD1=NT$3.6730

Significant Assets and Liabil_4

Significant Assets and Liabilities Denominated in Foreign Currencies - Summary of Realized and Unrealized Foreign Exchange Gain (Loss) (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of detailed information about financial instruments [line items]
Net Foreign Exchange Gain (Loss)	$ 1,460,876	$ 52,663	$ 1,056,639	$ 1,133,701
US Dollar [member] | US dollar equals to New Taiwan dollar [member]
Disclosure of detailed information about financial instruments [line items]
Exchange Rate	US$1=NT$27.68	US$1=NT$27.68	US$1=NT$28.48	US$1=NT$29.98
Net Foreign Exchange Gain (Loss)	$ 132,582	$ 4,780	$ (143,804)	$ (84,177)
New Taiwan Dollar [member]
Disclosure of detailed information about financial instruments [line items]
Net Foreign Exchange Gain (Loss)	$ 1,413,969	$ 50,972	$ 1,382,067	$ 1,203,823
Chinese Yuan [member] | Chinese Yuan equals to New Taiwan dollar [member]
Disclosure of detailed information about financial instruments [line items]
Exchange Rate	RMB1=NT$4.3415	RMB1=NT$4.3415	RMB1=NT$4.3648	RMB1=NT$4.2975
Net Foreign Exchange Gain (Loss)	$ (85,675)	$ (3,089)	$ (181,624)	$ 14,055

Operating Segments Informatio_2

Operating Segments Information - Summary of Segment Information (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)	Dec. 31, 2021USD ($)
Disclosure of operating segments [line items]
Operating revenue	$ 569,997,133	$ 20,547,842	$ 476,978,710	$ 413,182,184
Interest income	542,329	19,550	520,783	549,681
Interest expense	(2,798,935)	(100,899)	(3,437,228)	(4,186,855)
Depreciation and amortization	(54,524,277)	(1,965,547)	(51,259,065)	(50,466,841)
Share of the profit or loss of associates and joint ventures	899,700	32,433	547,612	182,275
Impairment loss	(126,766)	(4,571)	(992,273)	(601,207)
Segment profit before income tax	80,193,769	2,890,906	35,768,798	23,279,811
Expenditures for segment assets	74,417,541	2,682,681	59,024,201	63,073,887
Investments accounted for using the equity method	16,996,600		12,806,673	12,085,207	$ 612,711
Contract assets	5,607,209		4,782,904	5,897,316	202,134
Packaging segment [member]
Disclosure of operating segments [line items]
Operating revenue	272,543,899	9,824,942	218,666,071	198,916,897
Interest income	61,141	2,204	133,160	186,291
Interest expense	(1,604,107)	(57,827)	(2,244,280)	(3,403,475)
Depreciation and amortization	(34,384,500)	(1,239,528)	(32,333,229)	(33,456,831)
Share of the profit or loss of associates and joint ventures	737,650	26,591	362,133	75,303
Impairment loss	(86,997)	(3,137)	(218,600)	(601,066)
Segment profit before income tax	41,581,126	1,498,959	17,476,440	7,572,763
Expenditures for segment assets	48,531,368	1,749,509	38,643,303	35,462,305
Investments accounted for using the equity method	12,744,756		9,146,344	8,867,316	459,436
Contract assets	4,735,181		3,641,244	4,162,124	170,698
Testing segment [member]
Disclosure of operating segments [line items]
Operating revenue	49,978,736	1,801,685	47,271,074	42,658,686
Interest income	88,874	3,204	79,821	90,091
Interest expense	(405,648)	(14,623)	(564,269)	(545,609)
Depreciation and amortization	(13,819,080)	(498,164)	(14,189,024)	(12,379,703)
Share of the profit or loss of associates and joint ventures	66,107	2,383	99,670	39,852
Impairment loss	(39,769)	(1,434)	(773,673)	(141)
Segment profit before income tax	11,998,938	432,550	10,277,760	10,321,537
Expenditures for segment assets	16,773,513	604,669	14,275,397	23,966,051
Investments accounted for using the equity method	1,896,372		1,340,307	1,123,490	68,362
Contract assets	872,028		1,141,660	1,735,192	31,436
EMS segment [member]
Disclosure of operating segments [line items]
Operating revenue	239,488,267	8,633,319	204,690,669	165,789,479
Interest income	301,072	10,853	275,766	249,487
Interest expense	(629,584)	(22,696)	(443,519)	(255,404)
Depreciation and amortization	(4,336,266)	(156,318)	(2,877,546)	(2,534,825)
Share of the profit or loss of associates and joint ventures	95,943	3,459	85,809	67,120
Segment profit before income tax	8,528,675	307,450	8,438,766	6,082,106
Expenditures for segment assets	7,654,560	275,940	5,614,409	2,770,129
Investments accounted for using the equity method	2,355,472		2,320,022	2,094,401	$ 84,913
All other segments [member]
Disclosure of operating segments [line items]
Operating revenue	7,986,231	287,896	6,350,896	5,817,122
Interest income	91,242	3,289	32,036	284,458
Interest expense	(159,596)	(5,753)	(185,160)	(243,013)
Depreciation and amortization	(1,984,431)	(71,537)	(1,859,266)	(2,095,482)
Segment profit before income tax	18,085,030	651,947	(424,168)	(696,595)
Expenditures for segment assets	1,458,100	52,563	491,092	875,402
Adjustments and Eliminations [member]
Disclosure of operating segments [line items]
Interest income				(260,646)
Interest expense				260,646
Depreciation and amortization			(51,259,065)
Inter-group revenues [member]
Disclosure of operating segments [line items]
Operating revenue	0
Inter-group revenues [member] | Packaging segment [member]
Disclosure of operating segments [line items]
Operating revenue	7,244,889	261,171	10,436,168	5,370,963
Inter-group revenues [member] | Testing segment [member]
Disclosure of operating segments [line items]
Operating revenue	339,619	12,243	435,587	231,399
Inter-group revenues [member] | EMS segment [member]
Disclosure of operating segments [line items]
Operating revenue	27,825,073	1,003,067	21,472,775	60,638,567
Inter-group revenues [member] | All other segments [member]
Disclosure of operating segments [line items]
Operating revenue	7,527,260	271,350	7,234,303	7,431,399
Inter-group revenues [member] | Adjustments and Eliminations [member]
Disclosure of operating segments [line items]
Operating revenue	(42,936,841)	(1,547,831)	(39,578,833)	(73,672,328)
Operating segment [member]
Disclosure of operating segments [line items]
Operating revenue	612,933,974	22,095,673	516,557,543	486,854,512
Operating segment [member] | Packaging segment [member]
Disclosure of operating segments [line items]
Operating revenue	279,788,788	10,086,113	229,102,239	204,287,860
Operating segment [member] | Testing segment [member]
Disclosure of operating segments [line items]
Operating revenue	50,318,355	1,813,928	47,706,661	42,890,085
Operating segment [member] | EMS segment [member]
Disclosure of operating segments [line items]
Operating revenue	267,313,340	9,636,386	226,163,444	226,428,046
Operating segment [member] | All other segments [member]
Disclosure of operating segments [line items]
Operating revenue	$ 15,513,491	$ 559,246	$ 13,585,199	$ 13,248,521

Operating Segments Informatio_3

Operating Segments Information - Summary of Revenue from Major Products and Services (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of products and services [line items]
Operating revenue	$ 569,997,133	$ 20,547,842	$ 476,978,710	$ 413,182,184
Packaging service [member]
Disclosure of products and services [line items]
Operating revenue	272,543,899	9,824,942	218,666,071	198,916,897
Testing service [member]
Disclosure of products and services [line items]
Operating revenue	49,978,736	1,801,685	47,271,074	42,658,686
EMS
Disclosure of products and services [line items]
Operating revenue	239,488,267	8,633,319	204,690,669	165,789,479
Other products and services [member]
Disclosure of products and services [line items]
Operating revenue	$ 7,986,231	$ 287,896	$ 6,350,896	$ 5,817,122

Operating Segments Informatio_4

Operating Segments Information - Summary of Geographical Information (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)	Dec. 31, 2021USD ($)
Disclosure of geographical areas [line items]
Operating revenue	$ 569,997,133	$ 20,547,842	$ 476,978,710	$ 413,182,184
Noncurrent assets, excluding financial instruments, post-employment benefit assets and deferred tax assets	352,603,791		337,483,610		$ 12,711,023
United States [Member]
Disclosure of geographical areas [line items]
Operating revenue	353,500,361	12,743,344	297,117,001	245,521,027
Taiwan [member]
Disclosure of geographical areas [line items]
Operating revenue	94,598,067	3,410,168	64,829,301	51,244,470
Noncurrent assets, excluding financial instruments, post-employment benefit assets and deferred tax assets	252,525,376		239,353,978		9,103,294
Asia [Member]
Disclosure of geographical areas [line items]
Operating revenue	62,523,167	2,253,900	74,447,091	75,938,364
Europe [Member]
Disclosure of geographical areas [line items]
Operating revenue	57,910,641	2,087,622	39,477,306	38,613,132
Other geographical areas [member]
Disclosure of geographical areas [line items]
Operating revenue	1,464,897	$ 52,808	1,108,011	$ 1,865,191
Noncurrent assets, excluding financial instruments, post-employment benefit assets and deferred tax assets	34,702,992		31,875,938		1,251,009
China [member]
Disclosure of geographical areas [line items]
Noncurrent assets, excluding financial instruments, post-employment benefit assets and deferred tax assets	$ 65,375,423		$ 66,253,694		$ 2,356,720

Operating Segments Informatio_5

Operating Segments Information - Additional Information (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021TWD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020TWD ($)	Dec. 31, 2019TWD ($)
Disclosure of operating segments [line items]
Operating revenue	$ 569,997,133	$ 20,547,842	$ 476,978,710	$ 413,182,184
Packaging and EMS segments [member] | Customer One [member]
Disclosure of operating segments [line items]
Operating revenue	$ 158,624,032	$ 5,718,242	$ 145,952,908	103,987,781
Packaging And Testing segments [member] | Customer Two [member]
Disclosure of operating segments [line items]
Operating revenue				$ 44,653,072