AUO (AUOTY) 20-F 27 Mar 20 2019 FY Annual report (foreign) Financial data

Cover

Cover	12 Months Ended
	Dec. 31, 2019shares
Document Information [Line Items]
Document Type	20-F
Amendment Flag	false
Document Period End Date	Dec. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Entity Registrant Name	AU OPTRONICS CORP
Entity Central Index Key	0001172494
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Shell Company	false
Document Annual Report	true
Document Transition Report	false
Document Shell Company Report	false
Entity Interactive Data Current	Yes
Entity Emerging Growth Company	false
Entity Address, Country	TW
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding	9,499,245,115
Business Contact [Member]
Document Information [Line Items]
Contact Personnel Name	Benjamin Tseng
Entity Address, Address Line One	1 Li-Hsin Road 2
Entity Address, Address Line Two	Hsinchu Science Park
Entity Address, City or Town	Hsinchu
Local Phone Number	886-3-500-8800

Consolidated Statements of Fina

Consolidated Statements of Financial Position - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 80,449,772	$ 69,163,296
Financial assets at fair value through profit or loss-current	1,521,406	1,709,531
Accounts receivable, net	30,308,675	44,647,981
Accounts receivable from related parties, net	1,778,499	2,754,253
Other receivables from related parties	3,956	12,945
Current tax assets	79,886	69,156
Inventories	23,460,072	26,309,104
Other current financial assets	2,302,383	1,459,763
Other current assets	3,295,562	2,941,598
Total current assets	143,200,211	149,067,627
Noncurrent assets:
Financial assets at fair value through other comprehensive income-noncurrent	7,545,171	6,979,925
Investments in equity-accounted investees	5,999,479	6,285,865
Property, plant and equipment	206,734,543	221,586,475
Right-of-use assets	12,207,768
Investment property	1,555,130	730,306
Intangible assets	1,527,731	2,096,668
Deferred tax assets	5,181,617	6,632,668
Other noncurrent assets	2,405,346	5,171,646
Total noncurrent assets	243,156,785	249,483,553
Total Assets	386,356,996	398,551,180
Current liabilities:
Short-term borrowings	1,725,602	546,472
Current installments of long-term borrowings	9,535,198	29,595,931
Financial liabilities at fair value through profit or loss-current	18,859	22,115
Accounts payable	44,307,437	50,459,587
Accounts payable to related parties	6,950,828	8,161,186
Equipment and construction payable	6,316,902	11,231,333
Other payables to related parties	40,584	27,998
Current tax liabilities	1,531,588	3,520,469
Provisions-current	708,268	1,507,564
Lease liabilities-current	682,367
Other current liabilities	18,718,165	24,291,532
Total current liabilities	90,535,798	129,364,187
Noncurrent liabilities:
Long-term borrowings, excluding current installments	102,433,194	56,709,387
Provisions-noncurrent	1,053,290	1,030,485
Deferred tax liabilities	1,050,671	1,632,164
Lease liabilities-noncurrent	10,408,710
Other noncurrent liabilities	1,973,459	2,029,651
Total noncurrent liabilities	116,919,324	61,401,687
Total liabilities	207,455,122	190,765,874
Equity
Common stock, $10 par value	96,242,451	96,242,451
Capital surplus	60,543,683	60,620,224
Retained earnings	13,829,640	37,353,842
Other components of equity	(2,005,384)	(847,770)
Treasury shares	(1,013,423)
Equity attributable to shareholders of AU Optronics Corp.	167,596,967	193,368,747
Non-controlling interests	11,304,907	14,416,559
Total equity	178,901,874	207,785,306
Total Liabilities and Equity	$ 386,356,996	$ 398,551,180

Consolidated Statements of Fi_2

Consolidated Statements of Financial Position (Parenthetical) - $ / shares	Dec. 31, 2019	Dec. 31, 2018
Statement of financial position [abstract]
Par value per share	$ 10	$ 10

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of comprehensive income [abstract]
Net revenue	$ 268,791,694	$ 307,634,389	$ 341,028,267
Cost of sales	(268,335,751)	(279,494,885)	(279,986,522)
Gross profit	455,943	28,139,504	61,041,745
Selling and distribution expenses	(3,751,070)	(3,946,509)	(3,888,969)
General and administrative expenses	(7,363,234)	(7,978,267)	(8,158,940)
Research and development expenses	(9,809,587)	(9,546,863)	(9,854,712)
Other income	5,320,271	5,412,125	3,829,897
Other gains and losses	(1,595,614)	1,488,052	(976,560)
Finance costs	(3,251,370)	(2,663,605)	(2,867,861)
Share of profit of equity-accounted investees	149,907	311,714	239,006
Profit (loss) before income tax	(19,844,754)	11,216,151	39,363,606
Income tax (benefit) expense	1,336,155	322,374	(1,125,157)
Profit (loss) for the year	(21,180,909)	10,893,777	40,488,763
Items that will never be reclassified to profit or loss
Remeasurement of defined benefit obligations	188,110	(56,956)	(98,091)
Unrealized gain (loss) on equity investments at fair value through other comprehensive income	519,100	(756,287)
Equity-accounted investees - share of other comprehensive income	3,288	4,239	243
Related tax	(37,622)	38,908	155,930
Other comprehensive income that will not be reclassified to profit or loss, net of tax	672,876	(770,096)	58,082
Items that are or may be reclassified subsequently to profit or loss
Foreign operations - foreign currency translation differences	(2,505,864)	(785,772)	(2,255,410)
Net change in fair value of available-for-sale financial assets			1,146,422
Effective portion of changes in fair value of cash flow hedges			(21,992)
Equity-accounted investees - share of other comprehensive loss	(38,512)	(19,716)	(62,327)
Related tax	459,729	191,809	316,372
Other comprehensive income that will be reclassified to profit or loss, net of tax	(2,084,647)	(613,679)	(876,935)
Other comprehensive loss, net of tax	(1,411,771)	(1,383,775)	(818,853)
Total comprehensive income (loss) for the year	(22,592,680)	9,510,002	39,669,910
Profit (loss) attributable to:
Shareholders of AU Optronics Corp.	(18,767,191)	13,071,646	42,609,500
Non-controlling interests	(2,413,718)	(2,177,869)	(2,120,737)
Profit (loss) for the year	(21,180,909)	10,893,777	40,488,763
Total comprehensive income (loss) attributable to:
Shareholders of AU Optronics Corp.	(19,774,387)	11,996,308	42,146,146
Non-controlling interests	(2,818,293)	(2,486,306)	(2,476,236)
Total comprehensive income (loss) for the year	$ (22,592,680)	$ 9,510,002	$ 39,669,910
Earnings (loss) per share
Basic earnings (loss) per share	$ (1.96)	$ 1.36	$ 4.43
Diluted earnings (loss) per share	$ (1.96)	$ 1.34	$ 4.27

Consolidated Statements of Chan

Consolidated Statements of Changes in Equity - TWD ($) $ in Thousands	Total	Common stock [member]	Capital surplus [member]	Legal reserve [member]	Special Reserve [member]	Unappropriated earnings (deficit) [member]	Subtotal [member]	Cumulative translation differences [member]	Unrealized gains (losses) on financial assets at fair value through other comprehensive income [Member]	Unrealized gains (losses) on available-for-sale financial assets [member]	Unrealized gains (losses) on cash flow hedges [member]	Subtotal [member]	Treasury shares [member]	Equity attributable to shareholders of AU Optronics Corp. [member]	Non-controlling interests [member]
Beginning Balance at Dec. 31, 2016	$ 176,836,313	$ 96,242,451	$ 59,977,743	$ 2,657,792	$ 0	$ (1,207,174)	$ 1,450,618	$ 531,006	$ 0	$ 224,299	$ 21,992	$ 777,297	$ 0	$ 158,448,109	$ 18,388,204
Legal reserve	0	0	0	781,894	0	(781,894)	0	0	0	0	0	0	0	0	0
Cash dividends distributed to shareholders	(5,389,577)	0	0	0	0	(5,389,577)	(5,389,577)	0	0	0	0	0	0	(5,389,577)	0
Profit (loss) for the year	40,488,763	0	0	0	0	42,609,500	42,609,500	0	0	0	0	0	0	42,609,500	(2,120,737)
Other comprehensive income (loss), net of tax	(818,853)	0	0	0	0	57,881	57,881	(1,651,975)	0	1,152,732	(21,992)	(521,235)	0	(463,354)	(355,499)
Total comprehensive income (loss) for the year	39,669,910	0	0	0	0	42,667,381	42,667,381	(1,651,975)	0	1,152,732	(21,992)	(521,235)	0	42,146,146	(2,476,236)
Adjustments for changes in investees' equity	20,055	0	42,566	0	0	(16,090)	(16,090)	0	0	0	0	0	0	26,476	(6,421)
Differences between consideration and carrying amount arising from disposal of interest in subsidiary	0	0	518,196	0	0	0	0	0	0	0	0	0	0	518,196	(518,196)
Changes in non-controlling interests	1,681,150	0	0	0	0	0	0	0	0	0	0	0	0	0	1,681,150
Ending Balance at Dec. 31, 2017	212,817,851	96,242,451	60,538,505	3,439,686	0	35,272,646	38,712,332	(1,120,969)	0	1,377,031	0	256,062	0	195,749,350	17,068,501
Adjustments on initial application of new standards	(195)	0	0	0	0	73,020	73,020	0	1,303,816	(1,377,031)	0	(73,215)	0	(195)	0
Adjusted balance at January 1, 2018 | Increase (decrease) due to changes in accounting policy [member]	212,817,656	96,242,451	60,538,505	3,439,686	0	35,345,666	38,785,352	(1,120,969)	1,303,816	0	0	182,847	0	195,749,155	17,068,501
Legal reserve	0	0	0	3,235,942	0	(3,235,942)	0	0	0	0	0	0	0	0	0
Cash dividends distributed to shareholders	(14,436,368)	0	0	0	0	(14,436,368)	(14,436,368)	0	0	0	0	0	0	(14,436,368)	0
Profit (loss) for the year	10,893,777	0	0	0	0	13,071,646	13,071,646	0	0	0	0	0	0	13,071,646	(2,177,869)
Other comprehensive income (loss), net of tax	(1,383,775)	0	0	0	0	(16,862)	(16,862)	(306,716)	(751,760)	0	0	(1,058,476)	0	(1,075,338)	(308,437)
Total comprehensive income (loss) for the year	9,510,002	0	0	0	0	13,054,784	13,054,784	(306,716)	(751,760)	0	0	(1,058,476)	0	11,996,308	(2,486,306)
Changes in deemed contributions from shareholders	33,304	0	33,304	0	0	0	0	0	0	0	0	0	0	33,304	0
Adjustments for changes in investees' equity	8,051	0	28,891	0	0	158	158	0	0	0	0	0	0	29,049	(20,998)
Group reorganization	0	0	19,524	0	0	0	0	(22,225)	0	0	0	(22,225)	0	(2,701)	2,701
Disposal of equity investments at fair value through other comprehensive income	0	0	0	0	0	(50,084)	(50,084)	0	50,084	0	0	50,084	0	0	0
Changes in non-controlling interests	(147,339)	0	0	0	0	0	0	0	0	0	0	0	0	0	(147,339)
Ending Balance at Dec. 31, 2018	207,785,306	96,242,451	60,620,224	6,675,628	0	30,678,214	37,353,842	(1,449,910)	602,140	0	0	(847,770)	0	193,368,747	14,416,559
Legal reserve	0	0	0	1,016,060	0	(1,016,060)	0	0	0	0	0	0	0	0	0
Special reserve	0	0	0	0	847,770	(847,770)	0	0	0	0	0	0	0	0	0
Cash dividends distributed to shareholders	(4,812,122)	0	0	0	0	(4,812,122)	(4,812,122)	0	0	0	0	0	0	(4,812,122)	0
Profit (loss) for the year	(21,180,909)	0	0	0	0	(18,767,191)	(18,767,191)	0	0	0	0	0	0	(18,767,191)	(2,413,718)
Other comprehensive income (loss), net of tax	(1,411,771)	0	0	0	0	150,418	150,418	(1,680,072)	522,458	0	0	(1,157,614)	0	(1,007,196)	(404,575)
Total comprehensive income (loss) for the year	(22,592,680)	0	0	0	0	(18,616,773)	(18,616,773)	(1,680,072)	522,458	0	0	(1,157,614)	0	(19,774,387)	(2,818,293)
Changes in deemed contributions from shareholders	547	0	547	0	0	0	0	0	0	0	0	0	0	547	0
Treasury shares acquired	(1,013,423)	0	0	0	0	0	0	0	0	0	0	0	(1,013,423)	(1,013,423)	0
Adjustments for changes in investees' equity	(40,085)	0	(40,085)	0	0	0	0	0	0	0	0	0	0	(40,085)	0
Adjustments for changes in ownership of subsidiaries	0	0	(14,721)	0	0	(95,307)	(95,307)	0	0	0	0	0	0	(110,028)	110,028
Differences between acquisition price and carrying amount arising from acquisition of subsidiaries	0	0	(22,282)	0	0	0	0	0	0	0	0	0	0	(22,282)	22,282
Changes in non-controlling interests	(425,669)	0	0	0	0	0	0	0	0	0	0	0	0	0	(425,669)
Ending Balance at Dec. 31, 2019	$ 178,901,874	$ 96,242,451	$ 60,543,683	$ 7,691,688	$ 847,770	$ 5,290,182	$ 13,829,640	$ (3,129,982)	$ 1,124,598	$ 0	$ 0	$ (2,005,384)	$ (1,013,423)	$ 167,596,967	$ 11,304,907

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities:
Profit (loss) before income tax	$ (19,844,754)	$ 11,216,151	$ 39,363,606
Adjustments for:
depreciation	35,693,033	33,686,561	35,801,230
amortization	564,686	540,969	628,606
gain on financial instruments at fair value through profit or loss	(41,065)	(406,507)	(795,098)
interest expense	3,251,370	2,663,605	2,867,861
interest income	(885,520)	(841,615)	(612,210)
dividend income	(295,575)	(468,263)	(248,514)
share of profit of equity-accounted investees	(149,907)	(311,714)	(239,006)
gains on disposals of property, plant and equipment, net	(106,546)	(1,923,044)	(330,814)
losses (gains) on disposals of investments and financial assets, net	13,154	0	(42,788)
write-downs of inventories	5,185,504	5,171,752	3,756,726
impairment losses on assets	2,298,646	399,363	1,046,668
unrealized foreign currency exchange losses (gains)	(430,183)	545,856	776,962
others	26,468	(132,537)	(126,760)
Changes in operating assets and liabilities:
accounts receivable	13,685,703	(3,702,504)	4,643,577
receivables from related parties	984,744	(826,893)	659,522
inventories	(2,391,389)	(6,825,812)	(1,149,146)
other current assets	(926,326)	3,260,786	1,572,360
accounts payable	(5,014,990)	2,776,504	(2,489,088)
payables to related parties	(1,197,773)	503,293	(1,164,514)
net defined benefit liability	(89,422)	(82,176)	(103,668)
provisions	(759,948)	636,100	(911,810)
other current liabilities	(4,906,788)	(3,679,040)	3,974,959
Cash generated from operations	24,663,122	42,200,835	86,878,661
Cash received from interest income	919,840	815,890	628,223
Cash received from dividends	568,871	670,234	421,550
Cash paid for interest	(3,417,833)	(2,481,821)	(2,551,944)
Cash paid for income taxes	(2,003,361)	(1,004,444)	(1,013,159)
Net cash provided by operating activities	20,730,639	40,200,694	84,363,331
Cash flows from investing activities:
Acquisitions of financial assets at fair value through profit or loss	(3,668,175)	(2,509,528)	0
Disposals of financial assets at fair value through profit or loss	3,970,809	924,567	0
Acquisitions of financial assets at fair value through other comprehensive income	(47,182)	(3,452,722)	0
Disposals of financial assets at fair value through other comprehensive income	0	59,021	0
Acquisitions of available-for-sale financial assets	0	0	(201,434)
Proceeds from return of capital by available-for-sale financial assets	0	0	32,000
Acquisitions of equity-accounted investees	0	(684,756)	(397,000)
Proceeds from disposals of equity-accounted investees	904,050	0	56
Proceeds from return of capital by equity-accounted investees	0	99,200	0
Net cash outflow arising from acquisition of subsidiaries	0	(448,488)	0
Net cash inflow resulting from disposals of subsidiaries	0	51,387	276,393
Acquisitions of property, plant and equipment	(29,546,642)	(34,770,263)	(43,881,660)
Disposals of property, plant and equipment	170,880	6,408,057	1,149,649
Decrease (Increase) in refundable deposits	49,670	(169,666)	(404,233)
Increase in intangible assets	(1,711)	0	(196,781)
Decrease (Increase) in other financial assets	55,945	(4,635)	(44,469)
Net cash used in investing activities	(28,112,356)	(34,497,826)	(43,667,479)
Cash flows from financing activities:
Proceeds from short-term borrowings	2,576,584	2,526,082	10,548,495
Repayments of short-term borrowings	(1,388,334)	(5,343,976)	(7,644,568)
Proceeds from long-term borrowings	79,880,000	4,271,566	34,872,615
Repayments of long-term borrowings	(53,378,766)	(28,736,527)	(47,443,813)
Payments of lease liabilities	(694,922)	0	0
Guarantee deposits refunded	(1,828)	(13,402)	(34,654)
Cash dividends	(4,812,122)	(14,436,368)	(5,389,577)
Repurchase of treasury shares	(1,013,423)	0	0
Net change of non-controlling interests and others	(425,122)	(114,035)	1,681,150
Net cash provided by (used in) financing activities	20,742,067	(41,846,660)	(13,410,352)
Effect of exchange rate change on cash and cash equivalents	(2,073,874)	286,472	(2,456,132)
Net increase (decrease) in cash and cash equivalents	11,286,476	(35,857,320)	24,829,368
Cash and cash equivalents at January 1	69,163,296	105,020,616	80,191,248
Cash and cash equivalents at December 31	$ 80,449,772	$ 69,163,296	$ 105,020,616

Organization

Organization	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Organization	1. Organization AU Optronics Corp. (“AUO”) was founded on August 12, 1996 and is located in Hsinchu Science Park, the Republic of China (“ROC”). AUO’s main activities are the research, development, production and sale of thin film transistor liquid crystal displays (“TFT-LCDs”) and other flat panel displays used in a wide variety of applications. AUO also engages in the production and sale of solar modules and systems. AUO’s common shares have been publicly listed on the Taiwan Stock Exchange since September 2000, and its American Depositary Shares (“ADSs”) have been listed on the New York Stock Exchange (“NYSE”) since May 2002. On and from October 1, 2019, AUO's ADSs has delisted from the NYSE and begun trading on the over-the-counter (“OTC”) market. On September 1, 2001, October 1, 2006 and October 1, 2016, Unipac Optoelectronics Corp. (“Unipac”), Quanta Display Inc. (“QDI”) and Taiwan CFI Co., Ltd. (“CFI”) were merged with and into AUO, respectively. AUO is the surviving Company, whereas Unipac, QDI and CFI were dissolved. The principal operating activities of AUO and its subsidiaries (hereinafter referred to as “the Company”) are described in note 5(c)(2).

The Authorization of Financial

The Authorization of Financial Statements	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
The Authorization of Financial Statements	2. The Authorization of Financial Statements These consolidated financial statements were authorized for issue by the audit committee of the Board of Directors of AUO on March 20, 2020.

Application of New and Revised

Application of New and Revised Standards, Amendments and Interpretations	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Application of New and Revised Standards, Amendments and Interpretations	3. Application of New and Revised Standards, Amendments and Interpretations (a) New and revised standards, amendments and interpretations in issue but not yet effective In preparing the accompanying consolidated financial statements, the Company has not adopted the following International Financial Reporting Standards (“IFRS”), International Accounting Standards (“IAS”), Interpretations developed by the International Financial Reporting Interpretations Committee (“IFRIC”) or the former Standing Interpretations Committee (“SIC”) issued by the International Accounting Standards Board (“IASB”) (collectively, “IFRSs”). New, Revised or Amended Standards and Interpretations Effective Date (Note) Amendments to IFRS 3, Definition of a Business January 1, 2020 Amendments to IFRS 9, IAS39 and IFRS7, Interest Rate Benchmark Reform January 1, 2020 Amendments to IAS 1 and IAS 8, Definition of Material January 1, 2020 New, Revised or Amended Standards and Interpretations Effective Date (Note) Amendments to IFRS 10 and IAS 28, Sale or Contribution of Assets between an Investor and its Associate or Joint Venture Subject to IASB’s announcement IFRS 17, Insurance Contracts January 1, 2021 Amendments to IAS 1, Classification of Liabilities as Current or Non-Current January 1, 2022 Note: The aforementioned new, revised and amended standards and interpretations are effective for annual periods beginning on or after the respective effective dates. (b) As of the date that the accompanying consolidated financial statements were issued, the Company continues in assessing the potential impact of abovementioned standards or interpretations on its financial position and results of operations .

Changes in Significant Accounti

Changes in Significant Accounting Policies	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Changes in Significant Accounting Policies	4. Changes in Significant Accounting Policies The Company has initially applied IFRS 16 from January 1, 2019. The impact to the Company’s consolidated financial statements is set forth below. A number of other new standards are also effective from January 1, 2019 but they do not have a material effect on the Company’s consolidated financial statements. Due to the transition methods chosen by the Company in applying these standards, comparative information throughout these consolidated financial statements has not been restated to reflect the requirements of the new standards. (a) IFRS 16, Leases IFRS 16 sets out the accounting standards for leases, which replaces IAS 17, Leases and the related interpretations. Upon the initial application of IFRS 16, if the Company is a lessee, it is required to recognize a right-of-use asset and a lease liability on the statement of financial position for all leases with exception for leases of low-value assets and short-term leases which the Company may elect to apply the accounting method similar to the accounting for operating lease under IAS 17. Additionally, a depreciation expense charged on the right-of-use asset and an interest expense accrued on the lease liability, for which interest is computed by using effective interest method, are recognized separately on the statement of comprehensive income. On the statement of cash flows, cash payments for the principal amount of the lease liability is classified within financing activities . When IFRS 16 became effective, as a lessee, the Company applied this Standard using the modified retrospective approach with the cumulative effect of the initial application of this Standard recognized at the date of initial application. Comparative financial information, therefore, has not been restated. The Company is not required to make any adjustments on transition to IFRS 16 for leases in which it acts as a lessor, except for a sublease. The Company has accounted for those leases in accordance with IFRS 16 starting from the date of initial application. On January 1, 2019, based on the assessment of the remaining contractual terms and conditions agreed in head leases and subleases, all of the Company’s subleases were classified as operating leases. As at January 1, 2019, lease liabilities recognized for leases previously classified as an operating lease under IAS 17, except for leases of low-value asset and short-term leases, were measured at the present value of the remaining lease payments, discounted using the lessee’s incremental borrowing rate at the date of initial application. Right-of-use assets were measured at an amount equal to the lease liabilities, adjusted by the amount of any prepaid or accrued lease payments relating to that lease. The Company also tested right-of-use assets for impairment applying IAS 36. In addition, the Company used the following practical expedients when applying IFRS 16 to leases. a. Applied a single discount rate to a portfolio of leases with reasonably similar characteristics. b. Applied the exemption not to recognize right-of-use assets and lease liabilities to leases for which the lease term ends within 12 months of the date of initial application. c. Excluded initial direct costs from the measurement of the right-of-use assets at the date of initial application. d. Used hindsight when determining the lease term if the contract contains options to extend or terminate the lease. For leases that were classified as finance leases under IAS 17, the carrying amount of the right-of-use asset and the lease liability at the date of initial application The weighted average lessee’s incremental borrowing rate applied to lease liabilities recognized by the Company at January 1, 2019 is 1.87%. The reconciliation between the lease liabilities recognized and the future minimum lease payments of non-cancellable operating leases on December 31, 2018 is presented as follows: Amounts (in thousands) The future minimum lease payments of non-cancellable operating leases on December 31, 2018 $ 5,942,211 Recognition exemption for short-term leases (43,032 ) Other leases in scope of IFRS 16 125,328 Undiscounted amount on January 1, 2019 $ 6,024,507 Discounted amount using the incremental borrowing rate on January 1, 2019 $ 5,445,818 Finance lease liabilities recognized on December 31, 2018 2,496 Extension of lease that reasonably certain to be exercised 7,241,212 Lease liabilities recognized on January 1, 2019 $ 12,689,526 The following table summarized the impacts of initially applying IFRS 16 on the Company’s assets, liabilities and equity as at January 1, 2019. January 1, 2019 Carrying amount under IAS 17 and related standards and interpretations Adjustments from changes in accounting policies Carrying amount under IFRS 16 (in thousands) Other current assets $ 2,941,598 (6,638 ) 2,934,960 Property, plant and equipment 221,586,475 (1,765 ) 221,584,710 Right-of-use assets - 14,059,544 14,059,544 Other noncurrent assets 5,171,646 (1,364,111 ) 3,807,535 Impacts to total assets $ 12,687,030 Lease liabilities–current $ - 708,167 708,167 Other current liabilities 24,291,532 (931 ) 24,290,601 Lease liabilities–noncurrent - 11,981,359 11,981,359 Other noncurrent liabilities 2,029,651 (1,565 ) 2,028,086 Impacts to total liabilities $ 12,687,030 Impacts to total equity $ -

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Summary of Significant Accounting Policies	5. Summary of Significant Accounting Policies The significant accounting policies applied in the preparation of these consolidated financial statements are set out as below. The significant accounting policies have been applied consistently to all periods presented in these consolidated financial statements. (a) Statement of compliance The consolidated financial statements have been prepared in accordance with IFRSs as issued by the IASB. (b) Basis of preparation (1) Basis of measurement The consolidated financial statements have been prepared on the historical cost basis except for the following material items in the consolidated statements of financial position: (i) Financial instruments at fair value through profit or loss (including derivative financial instruments) (note 8); (ii) Financial assets at fair value through other comprehensive income (note 9); (iii) Available-for-sale financial assets measured at fair value (note 10); and (iv) Defined benefit asset (liability) is recognized as the fair value of the plan assets less the present value of the defined benefit obligation (note 27). (2) Functional and presentation currency The functional currency of each individual consolidated entity is determined based on the primary economic environment in which the entity operates. The Company’s consolidated financial statements are presented in New Taiwan Dollar (“NTD”), which is also AUO’s functional currency. All financial information presented in NTD has been rounded to the nearest thousand, unless otherwise noted. (c) Basis of consolidation (1) Principle of preparation of the consolidated financial statements The Company includes in its consolidated financial statements the results of operations of all controlled entities in which the Compa ny is exposed to, or has rights to, variable returns from its involvement with the entity and has the ability to affect those returns through its power over the entity The financial statements of subsidiaries are included in the consolidated financial statements from the date that control commences until the date that control ceases. Total comprehensive income (loss) in a subsidiary is allocated to the shareholders of AUO and the non-controlling interests even if this results in the non-controlling interests having a deficit balance. Subsidiaries’ financial statements are adjusted to align the accounting policies with those of the Company. Changes in the Company’s ownership interests in a subsidiary that do not result in a loss of control are accounted for as equity transactions. The carrying amounts of the Company’s investment and non-controlling interests are adjusted to reflect the changes in their relative interests in the subsidiary. Any difference between such adjustment and the fair value of the consideration paid or received is recognized directly in equity and attributed to shareholders of AUO. Upon the loss of control, the Company derecognizes the carrying amounts of the assets and liabilities of the subsidiary and non-controlling interests. Any interest retained in the former subsidiary is remeasured at fair value when control is lost. Any surplus or deficit arising from the loss of control is recognized in profit or loss. The gain or loss is measured as the difference between: (i) The aggregate of: a. the fair value of the consideration received, and b. the fair value of any retained investment in the former subsidiary at the date when the Company loses control. (ii) The aggregate of the carrying amount of the former subsidiary’s assets (including goodwill), liabilities and non-controlling interests at the date when the Company loses control. When the Company loses control of a subsidiary, the Company accounts for all amounts previously recognized in other comprehensive income in relation to that subsidiary on the same basis as would be required if the Company had directly disposed of the related assets or liabilities. (2) List of subsidiaries in the consolidated financial statements The consolidated entities were as follows: Name of Investor Name of Subsidiary Main Activities and Location Percentage of Ownership (%) December 31, 2018 December 31, 2019 AUO AU Optronics (L) Corp. (AULB) Holding and trading company (Malaysia) 100.00 100.00 AUO Konly Venture Corp. (Konly) Venture capital investment (Taiwan ROC) 100.00 100.00 AUO Ronly Venture Corp. (Ronly) Venture capital investment (Taiwan ROC) 100.00 100.00 AUO Space Money Inc. (SMI) Sales and leasing of content management system and hardware (Taiwan ROC) 100.00 100.00 AUO U-Fresh Technology Inc. (UTI) Planning, design and development of construction for environmental protection and related project management (Taiwan ROC) 100.00 100.00 AUO ComQi Ltd. (CQIL) Holding company (Israel) 100.00 (1) 100.00 AUO AU Optronics Europe B.V. (AUNL) Sales and sales support of TFT-LCD panels (Netherlands) 100.00 (2) 100.00 AUO, Konly and Ronly Darwin Precisions Corporation (DPTW) Manufacturing, design and sales of TFT-LCD modules, TV set, backlight modules and related parts (Taiwan ROC) 41.05 (3) 41.05 (3) AUO and Konly AUO Crystal Corp. (ACTW) Manufacturing and sales of ingots and solar wafers (Taiwan ROC) 96.02 (4) 100.00 (4) ACTW Sanda Materials Corporation (SDMC) Holding company (Taiwan ROC) 100.00 (5) 100.00 ACTW AUO Crystal (Malaysia) Sdn. Bhd. (ACMK) Manufacturing and sales of solar wafers (Malaysia) 100.00 100.00 SDMC M.Setek Co., Ltd. (M.Setek) Manufacturing and sales of ingots (Japan) 99.9991 99.9991 AULB AU Optronics Corporation America (AUUS) Sales and sales support of TFT-LCD panels (United States) 100.00 100.00 AULB AU Optronics Corporation Japan (AUJP) Sales support of TFT-LCD panels (Japan) 100.00 100.00 Name of Investor Name of Subsidiary Main Activities and Location Percentage of Ownership (%) December 31, 2018 December 31, 2019 AULB AU Optronics Korea Ltd. (AUKR) Sales support of TFT-LCD panels (South Korea) 100.00 100.00 AULB AU Optronics Singapore Pte. Ltd. (AUSG) Holding company and sales support of TFT-LCD panels (Singapore) 100.00 100.00 AULB AU Optronics (Czech) s.r.o. (AUCZ) (6) Assembly of solar modules (Czech Republic) 100.00 100.00 AULB AU Optronics (Shanghai) Co., Ltd. (AUSH) Sales support of TFT-LCD panels (PRC) 100.00 100.00 AULB AU Optronics (Xiamen) Corp. (AUXM) Manufacturing, assembly and sales of TFT-LCD modules (PRC) 100.00 100.00 AULB AU Optronics (Suzhou) Corp., Ltd. (AUSZ) Manufacturing, assembly and sales of TFT-LCD modules (PRC) 100.00 100.00 AULB AU Optronics Manufacturing (Shanghai) Corp. (AUSJ) Manufacturing and assembly of TFT-LCD modules; leasing (PRC) 100.00 100.00 AULB AU Optronics (Slovakia) s.r.o. (AUSK) Repairing of TFT-LCD modules (Slovakia Republic) 100.00 100.00 AULB AFPD Pte., Ltd. (AUST) Manufacturing TFT-LCD panels based on low temperature polysilicon technology (Singapore) 100.00 100.00 AULB AU Optronics (Kunshan) Co., Ltd. (AUKS) Manufacturing and sales of 51.00 51.00 AULB a.u. Vista Inc. (AUVI) Research and development and IP related business (United States) 100.00 100.00 AULB and DPTW BriView (L) Corp. (BVLB) Holding company (Malaysia) 100.00 100.00 AUSG AUO Energy (Tianjin) Corp. (AETJ) (6) Manufacturing and sales of solar modules (PRC) 100.00 - AUSG AUO Green Energy America Corp. (AEUS) Sales support of solar-related products (United States) 100.00 100.00 AUSG AUO Green Energy Europe B.V. (AENL) Sales support of solar-related products (Netherlands) 100.00 100.00 AUXM BriView (Xiamen) Corp. (BVXM) Manufacturing and sales of liquid crystal products and related parts (PRC) 100.00 100.00 AUSH AUO Care Information Tech. (Suzhou) Co., Ltd. (A-Care) Design, development and sales of software and hardware for health care industry (PRC) 100.00 100.00 Name of Investor Name of Subsidiary Main Activities and Location Percentage of Ownership (%) December 31, 2018 December 31, 2019 AUSH U-Fresh Technology (Suzhou) Co., Ltd. (UFSZ) Planning, design and development of construction project for environmental protection and related project management (PRC) 100.00 (7) 100.00 AUSH Edgetech Data Technologies (Suzhou) Corp., Ltd. (EDT) Design and sales of software and hardware integration system and equipment relating to intelligent manufacturing (PRC) 100.00 (7) 100.00 AUSH Mega Insight Smart Manufacturing (Suzhou) Corp., Ltd. (MIS) Development and licensing of software relating to intelligent manufacturing, and related consulting services (PRC) 100.00 (7) 100.00 UFSZ U-Fresh Environmental Technology (Shandong) Co., Ltd. (UFSD) Planning, design and development of construction project for environmental protection and related project management (PRC) - 100.00 (7) CQIL ComQi Holdings Ltd. (CQHLD) Holding company (United Kingdom) 100.00 (1) 100.00 CQHLD ComQi UK Ltd. (CQUK) Sales support of content management system (United Kingdom) 100.00 (1) 100.00 CQHLD ComQi Inc. (CQUS) Sales of content management system and hardware (United States) 100.00 (1) 100.00 CQHLD ComQi Canada Inc. (CQCA) Research and development of content management system (Canada) 100.00 (1) 100.00 CQUS JohnRyan Limited (JRUK) Development and sales of content management system and sales of related hardware (United Kingdom) - 100.00 (7) CQUS JohnRyan Inc. (JRUS) Development and sales of content management system and sales of related hardware (United States) - 100.00 (7) DPTW Darwin Precisions (L) Corp. (DPLB) Holding company (Malaysia) 100.00 100.00 DPTW Forhouse International Holding Ltd. (FHVI) Holding company (BVI) 100.00 100.00 DPTW Force International Holding Ltd. (FRVI) (6) Holding company (BVI) 100.00 - DPTW and FRVI Forefront Corporation (FFMI) Holding company (Mauritius) 100.00 100.00 (6) Name of Investor Name of Subsidiary Main Activities and Location Percentage of Ownership (%) December 31, 2018 December 31, 2019 FHVI Fortech International Corp. (FTMI) Holding company (Mauritius) 100.00 100.00 FHVI Forward Optronics International Corp. (FWSA) Holding company (Samoa) 100.00 100.00 FHVI Prime Forward International Ltd. (PMSA) Holding company (Samoa) 100.00 100.00 FFMI Forhouse Electronics (Suzhou) Co., Ltd. (FHWJ) Manufacturing of motorized treadmills (PRC) 100.00 100.00 FTMI Fortech Electronics (Suzhou) Co., Ltd. (FTWJ) Manufacturing and sales of backlight modules and related parts (PRC) 100.00 100.00 FWSA and FTMI Suzhou Forplax Optronics Co., Ltd. (FPWJ) Manufacturing and sales of precision plastic parts (PRC) 100.00 100.00 PMSA Fortech Electronics (Kunshan) Co., Ltd. (FTKS) Manufacturing and sales of backlight modules and related parts (PRC) 100.00 100.00 DPLB Darwin Precisions (Hong Kong) Limited (DPHK) Holding company (Hong Kong) 100.00 100.00 DPLB Darwin Precisions (Slovakia) s.r.o. (DPSK) Manufacturing and sales of automotive parts (Slovakia Republic) 100.00 100.00 DPHK Darwin Precisions (Suzhou) Corp. (DPSZ) Manufacturing and sales of backlight modules and related parts (PRC) 100.00 100.00 DPHK Darwin Precisions (Xiamen) Corp. (DPXM) Manufacturing and sales of backlight modules and related parts (PRC) 100.00 100.00 BVLB BriView (Hefei) Co., Ltd. (BVHF) Manufacturing and sales of liquid crystal products and related parts (PRC) 100.00 100.00 Note 1: In March 2018, the Company acquired 100% of the shareholdings of CQIL and its subsidiaries (hereinafter referred to as “ComQi”) and therefore, obtained control over ComQi. Refer to note 15 for further details. Note 2: As part of a business restructuring, AULB disposed all of its shareholdings in AUNL to AUO in December 2018. This was treated as an equity transaction as there was no change in control of AUNL by the Company. Note 3: Although the Company did not own more than 50% of the DPTW’s ownership interests, it was considered to have de facto control over the main operating policies of DPTW. As a result, DPTW was accounted for as a subsidiary of the Company. Note 4: As part of a business restructuring, Konly and Ronly successively disposed its shareholdings in ACTW to AUO in December 2018 and February 2019. This was treated as an equity transaction as there was no change in control of ACTW by the Company. Note 5: As part of a business restructuring, AUO, Konly and Ronly disposed all of their shareholdings in SDMC to ACTW during the second quarter of 2018. This was treated as an equity transaction as there was no change in control of SDMC by the Company. Note 6: As of December 31, 2019, AETJ and FRVI were liquidated and AUCZ is still in the process of liquidation. After the liquidation of FRVI, its ownership of FFMI was transferred to DPTW. Note 7: UFSZ was incorporated in February 2018. EDT and MIS were incorporated in August 2018. UFSD was incorporated in May 2019. JRUK and JRUS were incorporated in October 2019. (d) Foreign currency (1) Foreign currency transactions Transactions in foreign currencies are translated to the respective functional currencies of the individual entities of the Company at exchange rates at the dates of the transactions. Monetary assets and liabilities denominated in foreign currencies at the reporting date are retranslated to the functional currency at the exchange rate at that date and the resulting exchange differences are included in profit or loss for the year. Non-monetary assets and liabilities denominated in foreign currencies that are measured at fair value are retranslated to the functional currency at the exchange rate at the date when the fair value was determined. The resulting e xchange differences are included in profit or loss for the year except for those arising from the retranslation of non-monetary items in respect of which gains and losses are recognized directly in other comprehensive income, in which case, the exchange differences are also recognized directly in other comprehensive income Exchange differences arising from the effective portion of changes in the fair value of derivatives that are designated and qualified as cash flow hedges are recognized in other comprehensive income. (2) Foreign operations For the purpose of presenting consolidated financial statements, the assets and liabilities of the Company’s foreign operations are translated into NTD using the exchange rates at each reporting date. Income and expenses of foreign operations are translated at the average exchange rates for the period unless the exchange rates fluctuate significantly during the period; in that case, the exchange rates at the dates of the transactions are used. Foreign currency differences are recognized in other comprehensive income and accumulated in equity (attributed to shareholders of AUO and non-controlling interests as appropriate). (e) Classification of current and non-current assets and liabilities An asset is classified as current when: (1) The asset expected to realize, or intends to sell or consume, in its normal operating cycle; (2) The asset primarily held for the purpose of trading; (3) The asset expected to realize within twelve months after the reporting date; or (4) Cash and cash equivalent excluding the asset restricted to be exchanged or used to settle a liability for at least twelve months after the reporting date. All other assets are classified as non-current. A liability is classified as current when: (1) The liability expected to settle in its normal operating cycle; (2) The liability primarily held for the purpose of trading; (3) The liability is due to be settled within twelve months after the reporting date; or (4) The Company does not have an unconditional right to defer settlement of the liability for at least twelve months after the reporting 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. All other liabilities are classified as non-current. (f) Cash and cash equivalents Cash comprises cash balances and demand deposits. Cash equivalents comprise short-term highly liquid investments that are readily convertible into known amount of cash and are subject to an insignificant risk of changes in their fair value. Time deposits with short-term maturity but not for investments and other purposes and are qualified with the aforementioned criteria are classified as cash equivalent. (g) Financial instruments (1) Financial assets (policy applicable from January 1, 2018) (i) Classification of financial assets The Company classifies financial assets into the following categories: financial assets at amortized cost, financial assets at fair value through other comprehensive income and financial assets at fair value through profit or loss. When, and only when, the Company changes its business model for managing financial assets it shall reclassify all affected financial assets. a. Financial assets at amortized cost A financial asset is measured at amortized cost if it meets both of the following conditions and is not designated as measured at fair value through profit or loss: i. it is held within a business model whose objective is to hold financial assets to collect contractual cash flows; and ii. its contractual terms give rise on specified dates to cash flows that are solely payments of principal and interest on the principal amount outstanding. Such financial assets are initially recognized at fair value, plus any directly attributable transaction costs. Subsequently, these assets are measured at amortized cost using the effective interest method, less any impairment losses. Interest income, foreign exchange gains and losses, and recognition (reversal) of impairment losses, are recognized in profit or loss. b. Financial assets at fair value through other comprehensive income On initial recognition, the Company is able to make an irrevocable election to present subsequent changes in the fair value of investments in equity instruments that is not held for trading in other comprehensive income. This election is made on an instrument-by-instrument basis. Such financial assets are initially recognized at fair value, plus any directly attributable transaction costs. Subsequent to initial recognition, they are measured at fair value and changes therein are recognized in other comprehensive income and accumulated in equity － Dividends on investments in equity instruments are recognized on the date that the Company’s right to receive the dividends is established. c. Financial assets at fair value through profit or loss All financial assets not classified as at amortized cost or at fair value through other comprehensive income as described above are measured at fair value through profit or loss. This includes all derivative financial assets. Such financial assets are initially recognized at fair value, and attributable transaction costs are recognized in profit or loss as incurred. Subsequent to initial recognition, they are measured at fair value and changes therein are recognized in profit or loss. (ii) Impairment of financial assets The Company recognizes loss allowances for expected credit losses on financial assets at amortized cost, including cash and cash equivalents, receivables, refundable deposits and other financial assets, etc., and contract assets. Loss allowances for financial assets are deducted from the gross carrying amount of the assets. The recognition or reversal of the loss allowance is recognized in profit or loss. The expected credit loss is the weighted average of credit losses with the respective risks of a default occurring on the financial instrument as the weights. The Company measures the loss allowance for a financial instrument at an amount equal to lifetime expected credit losses, except for the financial instrument that is determined to have low credit risk at the reporting date and the credit risk thereof has not increased significantly since initial recognition, which is measured at an amount equal to the 12-month expected credit losses. For trade receivables and contract assets, t When determining whether the credit risk of a financial asset has increased significantly since initial recognition, the Company considers reasonable and supportable information that is relevant. This includes both qualitative and quantitative information and analysis, based on the Company’s historical experience and credit assessment as well as forward-looking information. In the circumstance that a financial asset is past due or the borrower is unlikely to pay its credit obligations to the Company in full, the Company considers the credit risk on that financial asset has significantly increased, or further, to be in default. At each reporting date, the Company assesses whether financial assets at amortized cost are credit-impaired. A financial asset is “credit-impaired” when one or more events that have a detrimental impact on the estimated future cash flows of the financial asset have occurred. (iii) De-recognition of financial assets The Company derecognizes financial assets when the contractual rights to the cash flows from the asset expire, or when the Company transfers substantially all the risks and rewards of ownership of the financial assets to another entity. (2) Financial assets (policy applicable before January 1, 2018) (i) Classification of financial assets The Company classifies financial assets into the following categories: financial assets at fair value through profit or loss, receivables and available-for-sale financial assets. a. Financial assets at fair value through profit or loss The Company has certain financial assets to hedge its exposure to foreign exchange risk arising from operating and financing activities. When a financial asset is not effective as a hedge, the Company accounts for it as a financial asset at fair value through profit or loss. b. Available-for-sale financial assets Available-for-sale financial assets are non-derivative financial assets that are either designated as available-for-sale or are not classified as receivables or financial assets at fair value through profit or loss. Available-for-sale financial assets are recognized initially at fair value, plus any directly attributable transaction cost. Subsequent to initial recognition, they are measured at fair value and changes therein, other than impairment losses, dividend income and foreign currency differences related to monetary financial assets, are recognized in other comprehensive income and presented within equity in unrealized gains (losses) on available-for-sale financial assets. When an investment is derecognized, the cumulative gain or loss in equity is reclassified to profit or loss. A regular way, purchase or sale of financial assets shall be recognized and derecognized, as applicable, using trade date accounting. Investments in equity instruments that do not have a quoted market price in an active market, and whose fair value cannot be reliably measured, are carried at their cost less any impairment losses. Cash dividends on equity instruments are recognized in profit or loss on the date that the Company’s right to receive dividends is established. c. Receivables Receivables are financial assets with fixed or determinable payments that are not quoted in an active market. Receivables comprise trade receivables and other receivables. Such assets are recognized initially at fair value, plus any directly attributable transaction costs. Subsequently, receivables are measured at amortized cost using the effective interest method, less any impairment. If the effect of discounting is immaterial, the short-term receivables are measured at the original amount. (ii) Impairment of financial assets Financial assets not measured at fair value through profit or loss are assessed at each reporting date for indicators of impairment. Financial assets are considered to be impaired if an objective evidence indicates that, as a result of one or more events that occurred after the initial recognition of the financial asset, the estimated future cash flows of those assets have been negatively impacted. When an available-for-sale equity security is considered to be impaired, cumulative gains or losses previously recognized in other comprehensive income are reclassified to profit or loss. Such impairment losses are not reversed through profit or loss. However, any subsequent recovery in the fair value of an impaired available-for-sale equity security is recognized in other comprehensive income and accumulated in other components of equity. For receivables, the Company first assesses whether objective evidence of impairment exists that are individually significant. If there is objective evidence that an impairment loss has occurred, the amount of impairment loss is assessed individually. For receivables other than those aforementioned, the Company groups those assets and collectively assesses them for impairment. An impairment loss for trade receivables is reflected in an allowance account against the receivables. When it is determined a receivable is uncollectible, it is written off from the allowance account. If any subsequent recovery of receivable previously written off can be related objectively to an event occurring after the impairment loss was recognized, it is credited against the allowance account and recognized in profit or loss. For equity instruments without a quoted market price in an active market, the objective evidence of impairment includes the investees’ financial information, current operating result, future business plans and relevant industry and public market information. An impairment loss for this kind of equity instruments is reduced from the carrying amount and any impairment loss recognized is not reversed through profit or loss in subsequent periods. Bad debt expenses and reversal of allowance for doubtful debts for trade receivables are recognized in general and administrative expenses while impairment losses and reversal of impairment for financial assets other than receivables are recognized in other gains and losses. (iii) De-recognition of financial assets The Company derecognizes financial assets when the contractual rights to the cash inflow from the asset expire, or when the Company transfers substantially all the risks and rewards of ownership of the financial assets to another entity. On de-recognition of a financial asset in its entirety, the difference between the carrying amount and the sum of the consideration received or receivable and any cumulative gain or loss that had been recognized in other comprehensive income is recognized in profit or loss. (3) Financial liabilities (i) Classification of financial liabilities The Company classifies financial liabilities into the following categories: financial liabilities at fair value through profit or loss and other financial liabilities. a. Financial liabilities at fair value through profit or loss The Company designates financial liabilities as held for trading for the purpose of hedging exposure to foreign exchange risk arising from operating and financing activities. When a financial liability is not effective as a hedge, the Company accounts for it as a financial liability at fair value through profit or loss. The Company designates financial liabilities, other than the one mentioned above, as at fair value through profit or loss at initial recognition. Attributable transaction costs are recognized in profit or loss as incurred. Financial liabilities in this category are subsequently measured at fair value and changes therein, which takes into account any interest expense, are recognized in profit or loss. b. Other financial liabilities Financial liabilities not classified as held for trading, or not designated as at fair value through profit or loss (including loans and borrowings, trade and other payables), are measured at fair value, plus any directly attributable transaction cost at the time of initial recognition. Subsequent to initial recognition, they are measured at amortized cost calculated using the effective interest method, except for insignificant recognition of interest expense from short-term borrowings and payables. Interest expense not capitalized as an asset cost is recognized in profit or loss. (ii) De-recognition of financial liabilities The Company derecognizes financial liabilities when the contractual obligation has been discharged, cancelled or expired. The difference between the carrying amount and the consideration paid or payable, including any non-cash assets transferred or liabilities assumed is recognized in profit or loss. (4) Offsetting of financial assets and liabilities The Company presents financial assets and liabilities on a net basis in the consolidated statement of financial position when the Company has the legally enforceable rights to offset, and intends to settle such financial assets and liabilities on a net basis or to realize the assets and settle the liabilities simultaneously. (h) Inventories The cost of inventories includes all necessary expenditures and charges for bringing the inventory to a stable, useable and marketable condition and location. The production overhead is allocated to finished goods and work in progress based on the normal capacity of the production facilities. Subsequently, inventories are measured at the lower of cost and net realizable value. Cost is determined using the weighted-average method. Net realizable value is calculated based on the estimated selling price less all estimated costs of completion and the estimated costs necessary to make the sale. (i) Noncurrent assets held for sale Noncurrent assets are classified as held for sale when their carrying amounts are expected to be recovered primarily through sale rather than through continuing use. Such noncurrent assets must be available for immediate sale in their present condition and the sale is highly probable within one year. When classified as held for sale, the assets are measured at the lower of their carrying amount and fair value less costs to sell. Impairment losses on initial classification as held for sale and subsequent gains or losses on re-measurement are recognized in profit or loss. However, subsequent gains are not recognized in excess of the cumulative impairment loss that has been recognized. When intangible assets and property, plant and equipment are classified as held for sale, they are no longer amortized or depreciated. In addition, once an equity-accounted investee is classified as held for sale, it is no longer equity accounted. (j) Investments in associates and joint ventures Associates are those entities in which the Company has the power to exercise significant influence, but not control or joint control, over their financial and operating policies. Joint venture is a joint arrangement whe reby the Company and other parties agreed to share the control of the arrangement, and have rights to the net assets of the arrangement. Unanimous consent from the parties sharing control is required when making decisions for the relevant activities of the arrangement. Investments in associates or joint ventures are accounted for using the equity method and are recognized initially at cost. The cost of the investment includes transaction costs. The consolidated financial statements include the Company’s share of the profit or loss and other comprehensive income of associates or joint ventures. When an associate or a joint venture incurs changes in its equity not derived from profit or loss and other comprehensive income, the Company recognizes all the equity changes in proportion to its ownership interest in the associate or joint venture as capital surplus provided that the ownership interest in the associate or joint venture remains unchanged. The difference between acquisition cost and fair value of associates’ or joint ventures’ identifiable assets and liabilities as of the acquisition date is accounted for as goodwill. Goodwill is included in the original investment cost of acquired associates or joint ventures and is not amortized. If the fair value of identified assets and liabilities is in excess of acquisition cost, the remaining excess over acquisition cost is recognized as a gain in profit or loss. The Company discontinues the use of the equity method from the date when its investment ceases to be an associate or a joint venture, and then measures the retained interests at fair value at that date. The difference between the carrying amount of the investment at the date the equity method was discontinued and the fair value of the retained interests along with any proceeds from disposing of a part interest in the associate or joint venture is recognized in profit or loss. Moreover, the Company accounts for all amounts previously recognized in other comprehensive income in relati

Use of Judgments and Estimates

Use of Judgments and Estimates	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Use of Judgments and Estimates	6. Use of Judgments and Estimates The preparation of the consolidated financial statements in conformity with IFRSs requires management to make judgments, estimates and assumptions that affect the application of the accounting policies and the reported amount of assets, liabilities, income and expenses. Actual results may differ from these estimates. Estimates and underlying assumptions are reviewed by management on an ongoing basis. Revisions to accounting estimates are recognized in the period in which the estimates are revised and in any future periods affected. Information about critical judgments, estimates and assumptions in applying accounting policies that have the significant effect on the amounts recognized in the consolidated financial statements is included in the following notes: (a) Estimate of provisions Provision for warranty is estimated when product revenue is recognized. The estimate has been made based on the quantities within the warranty period, the historical and anticipated warranty claims rate associated with similar products and services, and the projected unit cost of maintenance. The Company regularly reviews the basis of the estimate and if necessary, amends it as appropriate. There could be a significant impact on provision for warranty for any changes of the basis of the estimate. Provision for unsettled litigation and claims is recognized when it is probable that it will result in an outflow of the Company’s resources and the amount can be reasonably estimated. While the ultimate resolution of litigation and claims cannot be predicted with certainty, the final outcome or the actual cash outflow may be materially different from the estimated liability. (b) Impairment of long-term non-financial assets, other than goodwill In the process of evaluating the potential impairment of tangible and intangible assets other than goodwill, the Company is required to make subjective judgments in determining the independent cash flows, useful lives, expected future income and expenses related to the specific asset groups with the consideration of the usage mode of asset and the nature of industry. Any changes in these estimates based on changed economic conditions or business strategies could result in significant impairment charges or reversal in future years. (c) Impairment of goodwill The assessment of impairment of goodwill requires the Company to make subjective judgment to determine the identified CGUs, allocate the goodwill to relevant CGUs and estimate the recoverable amount of relevant CGUs. (d) Measurement of defined benefit obligations Accrued pension liabilities and the resulting pension expenses under defined benefit pension plans are calculated using the Projected Unit Credit Cost Method. Actuarial assumptions comprise the discount rate, rate of employee turnover, long-term average future salary increase, etc. Changes in economic circumstances and market conditions will affect these assumptions and may have a material impact on the amount of the expense and the liability. (e) Recognition of deferred tax assets Deferred tax assets are recognized to the extent that it is probable that future taxable profits will be available against which those deferred tax assets can be utilized. Assessment of the realization of the deferred tax assets requires management’s subjective judgment and estimate, including the future revenue growth and profitability, the sources of taxable income, the amount of tax credits can be utilized and feasible tax planning strategies. Changes in the global economic environment, the industry trends and relevant laws and regulations may result in adjustments to the deferred tax assets. (f) Estimate of variable consideration of revenue (applicable from January 1, 2018) The Company estimates the amount of variable consideration by using methods either the expected value or the most likely amount based on historical experience, market and economic situation and any known factors that would significantly affect the estimates. The amount of variable consideration is recognized as a reduction of revenue in the same period the related revenue is recognized. The Company periodically reviews the reasonableness of the estimated variable consideration. However, the adequacy of estimations may be affected by factors such as market price competition and the evolution of product technology, which could result in significant adjustments to the variable consideration. (g) Estimate of allowance for sales returns and discounts (applicable before January 1, 2018) The Company records a provision as the deduction of revenue for estimated future sales returns and other allowances in the same period the related revenue is recognized. Estimated sales returns and other allowances are generally made and adjusted based on historical experience, management’s judgment and any known factors that would significantly affect the allowance, and management periodically reviews the reasonableness of the estimates. (h) Valuation of inventories As inventories are stated at the lower of cost or net realizable value, the Company estimates the net realizable value of inventories for obsolescence and unmarketable items at the end of reporting period and then writes down the cost of inventories to net realizable value. The net realizable value of the inventory is mainly determined based on assumptions of future demand within a specific time horizon. Due to the rapid industrial transformation, there may be significant changes in the net realizable value of inventories.

Cash and Cash Equivalents

Cash and Cash Equivalents	12 Months Ended
	Dec. 31, 2019
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Cash and Cash Equivalents	7. Cash and Cash Equivalents December 31, 2018 2019 (in thousands) Cash on hand, demand deposits and checking accounts $ 30,134,051 46,290,722 Time deposits 38,939,198 34,124,011 Government bonds with reverse repurchase agreements 90,047 35,039 $ 69,163,296 80,449,772 Refer to note 41 for the disclosure of credit risk, currency risk and sensitivity analysis of the financial instruments of the Company. As at December 31, 2018 and 2019, no cash and cash equivalents were pledged with banks as collaterals.

Financial Assets and Liabilitie

Financial Assets and Liabilities at Fair Value through Profit or Loss ("FVTPL")	12 Months Ended
	Dec. 31, 2019
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Financial Assets and Liabilities at Fair Value through Profit or Loss ("FVTPL")	8. Financial Assets and Liabilities at Fair Value through Profit or Loss (“FVTPL”) December 31, 2018 2019 (in thousands) Financial assets mandatorily measured at FVTPL: Foreign currency forward contracts $ 70,074 42,815 Structured deposits 1,639,457 1,478,591 $ 1,709,531 1,521,406 Financial liabilities held for trading: Foreign currency forward contracts $ 22,115 18,859 The Company entered into derivative contracts to manage the exposure to currency risk arising from operating activities. Refer to note 41 for the disclosure of the Company’s credit and currency risks related to financial instruments. As of December 31, 2018 and 2019, the Company’s outstanding foreign currency forward contracts were as follows: December 31, 2018 Contract item Maturity date Contract amount (in thousands) Sell USD / Buy NTD Jan. 2019 USD223,000 / NTD6,858,785 Sell USD / Buy JPY Jan. 2019 – Apr. 2019 USD147,470 / JPY16,493,633 Sell NTD / Buy JPY Jan. 2019 – Mar. 2019 NTD2,054,260 / JPY7,400,000 Sell USD / Buy CNY Jan. 2019 – Jun. 2019 USD87,000 / CNY597,420 December 31, 2018 Contract item Maturity date Contract amount (in thousands) Sell EUR / Buy JPY Jan. 2019 EUR12,000 / JPY1,536,180 Sell EUR / Buy USD Jan. 2019 EUR28,500 / USD32,441 Sell EUR / Buy CZK Jan. 2019 – Mar. 2019 EUR3,240 / CZK84,081 Sell USD / Buy MYR Jan. 2019 – Mar. 2019 USD879 / MYR3,670 Sell CNY / Buy JPY Jan. 2019 – Feb. 2019 CNY60,800 / JPY981,383 Sell USD / Buy SGD Jan. 2019 USD5,793 / SGD7,940 Sell CNY / Buy USD Jan. 2019 – Feb. 2019 CNY853,328 / USD124,000 December 31, 2019 Contract item Maturity date Contract amount (in thousands) Sell USD / Buy NTD Jan. 2020 USD176,600 / NTD5,319,611 Sell USD / Buy JPY Jan. 2020 – Apr. 2020 USD47,292 / JPY5,150,510 Sell USD / Buy CNY Jan. 2020 – Jun. 2020 USD61,500 / CNY432,823 Sell USD / Buy SGD Jan. 2020 – Feb. 2020 USD39,276 / SGD53,372 Sell USD / Buy MYR Jan. 2020 – Mar. 2020 USD703 / MYR2,905 Sell CNY / Buy USD Feb. 2020 – Mar. 2020 CNY1,935,305 / USD276,672 Sell EUR / Buy JPY Jan. 2020 – Feb. 2020 EUR23,000 / JPY2,788,285 Sell HKD / Buy USD Jan. 2020 HKD60,177 / USD7,721

Financial Assets at Fair Value

Financial Assets at Fair Value through Other Comprehensive Income ("FVTOCI")	12 Months Ended
	Dec. 31, 2019
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Financial Assets at Fair Value through Other Comprehensive Income ("FVTOCI")	9. Financial Assets at Fair Value through Other Comprehensive Income (“FVTOCI”) December 31, 2018 2019 (in thousands) Investments in equity instruments at FVTOCI: Equity securities – listed stocks $ 6,803,900 7,356,501 Equity securities – non-listed stocks 176,025 188,670 $ 6,979,925 7,545,171 The purpose that the Company invests in the abovementioned equity securities is for long-term strategies, but rather for trading purpose. Therefore, those equity securities are designated as financial assets at FVTOCI. If the value of these equity securities appreciates or depreciates by 10% at the reporting date, other comprehensive income would increase or decrease by $697,993 thousand and $754,517 thousand for the years ended December 31, 2018 and 2019, respectively.

Available-for-sale Financial As

Available-for-sale Financial Assets-noncurrent	12 Months Ended
	Dec. 31, 2019
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Available-for-sale Financial Assets-noncurrent	10. Available-for-sale Financial Assets － The Company determined part of its available-for-sale financial assets was impaired, and there is a remote chance of future recovery. As a result, the Company recognized an impairment loss of $30,000 thousand for the year ended December 31, 2017. Some of the available-for-sale securities held by the Company were publicly traded equity shares. If the share price of these securities appreciates or depreciates by 10% at the reporting date, other comprehensive income would increase or decrease by $417,032 thousand for the year ended 2017. After the application of IFRS 9 from January 1, 2018, the equity investments classified as available-for-sale financial assets were designated as financial assets at FVTOCI. See note 9 for related disclosure.

Accounts Receivable, net (Inclu

Accounts Receivable, net (Including Related and Unrelated Parties)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Accounts Receivable, net (Including Related and Unrelated Parties)	11. Accounts Receivable, net (Including Related and Unrelated Parties) December 31, 2018 2019 (in thousands) Accounts receivable $ 47,453,087 32,104,912 Less: loss allowance (50,853 ) (17,738 ) $ 47,402,234 32,087,174 Accounts receivable, net $ 44,647,981 30,308,675 Accounts receivable from related parties, net $ 2,754,253 1,778,499 The Company measures loss allowance for accounts receivable using the simplified approach under IFRS 9 with the lifetime expected credit losses. Analysis of expected credit losses which was measured based on the aforementioned method, was as follows: December 31, 2018 Carrying amount of accounts receivable Weighted-average loss rate Loss allowance for lifetime expected credit losses (in thousands) (in thousands) Not past due $ 46,529,408 0.00 % 89 Past due less than 60 days 862,373 0.05 % 439 Past due 61~180 days 11,090 0.98 % 109 Past due over 180 days 475 100 % 475 $ 47,403,346 1,112 December 31, 2019 Carrying amount of accounts receivable Weighted-average loss rate Loss allowance for lifetime expected credit losses (in thousands) (in thousands) Not past due $ 31,061,173 0.00 % 1 Past due less than 60 days 1,010,918 0.00 % 4 Past due 61~180 days 15,233 0.95 % 145 $ 32,087,324 150 In addition, there was objective evidence indicating that, under reasonable expectation, some of the accounts receivable would not be recovered in total, therefore, the Company recognized a loss allowance of $49,741 thousand and $17,588 thousand as of December 31, 2018 and 2019, respectively. The movement of the loss allowance for accounts receivable was as follows: For the years ended December 31, 2017 (i) Individually assessed for impairment Collectively assessed for impairment 2018 2019 (in thousands) Balance at beginning of the year $ 41,812 62,805 93,053 50,853 Provisions (reversals) charged to (against) expense (28,236 ) 18,396 (24,302 ) (14,543 ) Write-offs (6 ) - (17,985 ) (18,404 ) Effect of changes in foreign currency exchange rates (805 ) (913 ) 87 (168 ) Balance at end of the year $ 12,765 80,288 50,853 17,738 (i) The movement of 2017 was under IAS 39. There were no adjustments for the beginning balance of 2018 on the initial application of IFRS 9. The payment terms granted to customers are generally 25 to 60 days from the end of the month during which the invoice is issued. This term is consistent with practices in our industry, and thus, no financing components involved. Information about the Company’s exposure to credit risk is included in note 41. The Company entered into financing facilities with banks to factor certain of its accounts receivable without recourse. As at December 31, 2018, the Company did not sell its accounts receivables to banks. As at December 31, 2019, the Company’s accounts receivables sold and derecognized were as follows: December 31, 2019 Underwriting bank Factoring Amount Amount Principal (in thousands) (in thousands) (in thousands) CTBC bank USD 152,000 USD 18,526 NTD 500,000 See Notes(a)~(d) Taipei Fubon Bank USD 120,000 USD 56,020 NTD 1,500,000 See Notes(a)~(d) DBS Bank USD 154,000 USD 56,730 NTD 1,520,000 See Notes(a)~(d) Bank of Taiwan USD 250,000 USD 15,718 USD 14,000 See Notes(a)~(d) Note (a): Under these facilities, the Company transferred accounts receivable to the respective underwriting banks, which are without recourse subject to the underwriting consents. Note (b): The Company informed its customers pursuant to the respective facilities to make payment directly to the respective underwriting banks. Note (c): As of December 31, 2019, total outstanding receivables after the above transactions, net of fees charged by underwriting banks, of $487,754 thousand was recognized under other current financial assets. In addition, interest rate for the balance of advanced amount as of December 31, 2019 was ranging from 1.07% to 2.44%. Note (d): To the extent of the amount transferred to the underwriting banks, risks of non-collection or potential payment default by customers in the event of insolvency are borne by respective banks. The Company is not responsible for the collection of receivables subject to these facilities, or for any legal proceedings and costs thereof in collecting these receivables. In case any commercial dispute between the Company and customers or other reasons results in the Company’s failure to perform the obligation under these facilities, the banks have requested the Company to issue promissory notes in the amounts equal to 10 percent of respective facilities or to transfer receivables in the amounts equal to 10 percent of respective facilities. Other than such arrangements, no collaterals were provided by the Company.

Inventories

Inventories	12 Months Ended
	Dec. 31, 2019
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Inventories	12. Inventories December 31, 2018 2019 (in thousands) Finished goods $ 9,406,248 9,005,001 Work-in-progress 11,133,846 9,537,700 Raw materials 5,769,010 4,917,371 $ 26,309,104 23,460,072 For the years ended December 31, 2017, 2018 and 2019, the amounts recognized as cost of sales in relation to inventories were $279,986,522 thousand, $279,494,885 thousand and $268,335,751 thousand, respectively. Charges for inventories written down to net realizable value, which were also included in cost of sales, amounted to $3,756,726 thousand, $5,171,752 thousand and $5,185,504 thousand for the years ended December 31, 2017, 2018 and 2019, respectively. As at December 31, 2018 and 2019, none of the Company’s inventories was pledged as collateral.

Noncurrent Assets Held for Sale

Noncurrent Assets Held for Sale	12 Months Ended
	Dec. 31, 2019
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Noncurrent Assets Held for Sale	13. Noncurrent Assets Held for Sale In December 2016, M.Setek decided to dispose part of its land and buildings to TAKEEI Corporation and other companies, and has reclassified certain of these assets for reclassification as noncurrent assets held for sale. Disposal transactions of aforementioned land and buildings, together with certain assets presented as property, plant and equipment, were completed between March 2017 to August 2017. The total selling price (net of costs of disposal) and gain on disposal were $837,103 thousand and $215,478 thousand, respectively. In October 2017, in relation to compulsory imposition under regulatory plan and urban construction plan, FTKS has entered into a compensation agreement with Kunshan Economic and Technology Development Zone. The imposed land use right, plant buildings and its related appendages have been reclassified as noncurrent assets held for sale. The disposal transaction was completed in March 2018 and the proceeds from disposal have been fully received. The selling price (net of costs of disposal) and gain on disposal amounted to $983,082 thousand and $561,815 thousand, respectively. In December 2017, in order to enhance the utilization of the Company’s assets and to increase its working capital, BVHF has entered into a real estate transfer agreement with Hefei Heng Chuang Intelligent Technology Co., Ltd. to dispose its land use right, plant buildings and its related appendages. The aforementioned assets have been reclassified as noncurrent assets held for sale. The disposal transaction was completed in June 2018 and the proceeds from disposal have been fully received. The selling price (net of costs of disposal) and gain on disposal amounted to $2,204,576 thousand and $228,754 thousand, respectively.

Investments in Equity-accounted

Investments in Equity-accounted Investees	12 Months Ended
	Dec. 31, 2019
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Investments in Equity-accounted Investees	14. Investments in Equity-accounted Investees December 31, 2018 2019 (in thousands) Associates $ 5,973,127 5,820,759 Joint ventures 312,738 178,720 $ 6,285,865 5,999,479 (a) Associates Principal December 31, 2018 December 31, 2019 Name of associate Principal activities place of business Ownership interest Amount Ownership interest Amount % (in thousands) % (in thousands) Lextar Electronics Corp. (“Lextar”) Manufacturing and sales of Light Emitting Diode Taiwan ROC 27 $ 3,082,178 27 $ 2,909,521 Star Shining Energy Corporation Investment Taiwan ROC 33 1,002,874 33 1,015,512 Raydium Semiconductor Corporation (“Raydium”) IC design Taiwan ROC 18 716,381 17 740,504 Daxin Materials Corp. (“Daxin”) Research, manufacturing, and sales of display related chemicals Taiwan ROC 25 654,940 25 688,813 Star River Energy Corp. (“SREC”) Investment Taiwan ROC 34 434,421 34 444,550 Others 82,333 21,859 $ 5,973,127 $ 5,820,759 None of the above associates is considered individually material to the Company. The following table summarized the amount recognized by the Company at its share of those associates. For the years ended December 31, 2017 2018 2019 (in thousands) The Company’s share of profits of associates $ 251,699 307,992 195,865 The Company’s share of other comprehensive loss of associates (62,084 ) (15,477 ) (35,224 ) The Company’s share of total comprehensive income of associates $ 189,615 292,515 160,641 (b) Joint ventures None of the joint ventures is considered individually material to the Company. The following table summarized the amount recognized by the Company at its share of those joint ventures. For the years ended December 31, 2017 2018 2019 (in thousands) The Company’s share of profits (loss) of joint ventures $ (12,693 ) 3,722 (45,958 ) The Company’s share of other comprehensive income of joint ventures - - - The Company’s share of total comprehensive income (loss) of joint ventures $ (12,693 ) 3,722 (45,958 ) As at December 31, 2018 and 2019, none of the Company’s investments in equity-accounted investees was pledged as collateral.

Acquisition of Subsidiaries

Acquisition of Subsidiaries	12 Months Ended
	Dec. 31, 2019
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Acquisition of Subsidiaries	15. Acquisition of Subsidiaries In March 2018, the Company obtained control over ComQi by acquiring 100% of shareholdings of ComQi. ComQi is engaged in integration service of content management system and hardware. Through the acquisition of ComQi, the Company expects to be able to provide a total solution for the upstream and downstream of public information displays. If the acquisition had taken place on January 1, 2018, management estimated that the Company’s consolidated revenue and net profit for the year ended December 31, 2018 would have been $307,673,560 thousand and $7,956,563 thousand, respectively. In determining these amounts, management had assumed that the fair value adjustments that arose on the acquisition date would have been the same if the acquisition had taken place on January 1, 2018. The aforementioned pro-forma information is presented for illustrative purposes only and is not necessarily an indication of revenue and results of operations of the Company that would have been achieved had the acquisition been completed on January 1, 2018, nor is it intended to be a projection of future results. Acquisition-related costs of $12,191 thousand on legal fees and due diligence fees were expensed and recognized in general and administrative expenses in the consolidated statement of comprehensive income for the year ended December 31, 2018. The following table summarized each major class of consideration transferred, the assets acquired and liabilities assumed at the acquisition date and the amount of goodwill recognized. (a) Consideration transferred Amounts (in thousands) Cash $ 467,920 Contingent consideration 283,354 $ 751,274 In accordance with the terms of the contingent consideration, in the event that ComQi’s annual net revenue and annual recurring revenue for the year ended December 31, 2018 are greater than the agreed revenue targets in the agreement, the Company should pay additional consideration of USD4,000 thousand and USD7,000 thousand, respectively, to the original shareholders of ComQi. Under the arrangement of the contingent consideration, the potential undiscounted amount of the contingent payment that the Company might have to pay was between USD0 and USD11,000 thousand. The fair value of the contingent consideration estimated using Monte Carlo simulation amounted to $283,354 thousand. The fair value measurement was based on the significant unobservable inputs in the market and categorized as a Level 3 fair value under IFRS 13. The significant inputs in the valuation technique used are discount rate of 8.5%, revenue volatility rate of 30.8% and AUO’s credit spread of 0.88%. As ComQi’s annual net revenue and annual recurring revenue for the year ended December 31, 2018 were not greater than the agreed revenue targets in the agreement, the Company remeasured the fair value of the contingent consideration and determined the value was zero. The change in the fair value of the contingent consideration of $283,354 thousand was not a measurement period adjustment, and therefore, was recognized under other gains and losses in the consolidated statement of comprehensive income for the year ended December 31, 2018. (b) Identifiable assets acquired and liabilities assumed The following table summarized the fair value of identifiable assets acquired and liabilities assumed recognized at the acquisition date: Fair value (in thousands) Cash $ 19,432 Accounts receivable and other current assets 36,851 Property, plant and equipment 3,712 Intangible assets 150,436 Accounts payable and other current liabilities (57,361 ) Other liabilities (2,120 ) $ 150,950 (c) Goodwill arising from the acquisition for which is attributable mainly to the synergies expected to be achieved from integrating ComQi into the Company’s existing business has been recognized as follows: Amounts (in thousands) Consideration transferred $ 751,274 Less: Fair value of identifiable net assets (150,950 ) $ 600,324

Disposal of Part of Ownership I

Disposal of Part of Ownership Interest in Subsidiary without Losing Control	12 Months Ended
	Dec. 31, 2019
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Disposal of Part of Ownership Interest in Subsidiary without Losing Control	16. Disposal of Part of Ownership Interest in Subsidiary without Losing Control In November 2017, the Company disposed its ownership interest in DPTW totaling of 9.99% with consideration (net of costs of disposal) amounting to $1,776,984 thousand in cash. The effect of changes in ownership interest of the subsidiary which was attributable to owners of the parent was summarized as follows: For the year ended December 31, 2017 (in thousands) Consideration received $ 1,776,984 Carrying amount of the equity interest disposed of (1,190,529 ) Capital surplus – changes in ownership interest of subsidiary (12,099 ) Other equity – effect from foreign currency translation differences arising from foreign operations (56,160 ) Capital surplus – differences between consideration and carrying amount arising from disposal of interest in subsidiary $ 518,196

Disposal of Subsidiaries

Disposal of Subsidiaries	12 Months Ended
	Dec. 31, 2019
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Disposal of Subsidiaries	17. Disposal of Subsidiaries The Company disposed all its shareholdings in Fargen Power Corporation and TronGen Power Corporation to SSEC, an associate of the Company, in December 2017 with consideration amounting to $480,000 thousand in cash. The gain on disposal amounting to $76,331 thousand was recognized under other gains and losses in the consolidated statement of comprehensive income. The carrying amounts of the assets and liabilities of the subsidiaries disposed of by the Company were as follows: Amounts (in thousands) Cash and cash equivalents $ 203,607 Accounts receivable and other receivables 4,513 Other current assets 38,649 Property, plant and equipment 260,828 Other assets 54,397 Payable for equipment (71,076 ) Accrued expense and other current liabilities (3,062 ) Long-term borrowings (84,187 ) Net assets disposed of $ 403,669 The Company disposed all its shareholdings in ChampionGen Power Corporation to SSEC in September 2018 with consideration amounting to $116,000 thousand in cash. The gain on disposal amounting to $17,269 thousand was recognized under other gains and losses in the consolidated statement of comprehensive income. The carrying amounts of the assets and liabilities of the subsidiary disposed of by the Company were as follows: Amounts (in thousands) Cash and cash equivalents $ 70,516 Other current assets 48,148 Payable for equipment (19,933 ) Net assets disposed of $ 98,731

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2019
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Property, Plant and Equipment	18. Property, Plant and Equipment For the year ended December 31, 2018 Balance, Beginning of Year Additions Disposal or write off Reclassification, effect of change in exchange rate and others Balance, (in thousands) Cost: Land $ 9,008,659 - (161,728 ) 12,392 8,859,323 Buildings 124,010,869 53,706 (5,271,527 ) 2,426,312 121,219,360 Machinery and equipment 800,164,310 2,145,769 (13,164,282 ) 46,787,823 835,933,620 Other equipment 29,359,148 5,077,326 (1,775,217 ) 2,467,867 35,129,124 962,542,986 7,276,801 (20,372,754 ) 51,694,394 1,001,141,427 Accumulated depreciation and impairment loss: Buildings 33,825,375 3,097,807 (1,754,678 ) 862,822 36,031,326 Machinery and equipment 707,334,411 25,620,993 (12,828,449 ) 1,706,393 721,833,348 Other equipment 23,717,580 5,367,124 (1,775,840 ) 782,123 28,090,987 764,877,366 34,085,924 (16,358,967 ) 3,351,338 785,955,661 Prepayments for purchase of land and equipment, and construction in progress 27,267,469 26,228,260 - (47,095,020 ) 6,400,709 Net carrying amounts $ 224,933,089 221,586,475 For the year ended December 31, 2019 Balance, Beginning of Year Adjustments on initial application of new standards Additions Disposal or write off Reclassification, effect of change in exchange rate and others Balance, (in thousands) Cost: Land $ 8,859,323 - - - (675 ) 8,858,648 Buildings 121,219,360 - 325,184 (9,075 ) (1,838,220 ) 119,697,249 Machinery and equipment 835,933,620 - 1,320,958 (9,123,165 ) 13,450,424 841,581,837 Other equipment 35,129,124 (2,620 ) 4,910,462 (5,764,497 ) 1,561,968 35,834,437 1,001,141,427 (2,620 ) 6,556,604 (14,896,737 ) 13,173,497 1,005,972,171 Accumulated depreciation and impairment loss: Buildings 36,031,326 - 4,195,265 (9,021 ) (1,046,822 ) 39,170,748 Machinery and equipment 721,833,348 - 27,348,497 (9,080,856 ) (2,808,161 ) 737,292,828 Other equipment 28,090,987 (855 ) 5,575,376 (5,747,362 ) (271,736 ) 27,646,410 785,955,661 (855 ) 37,119,138 (14,837,239 ) (4,126,719 ) 804,109,986 Prepayments for purchase of land and equipment, and construction in progress 6,400,709 - 18,469,787 (4,837 ) (19,993,301 ) 4,872,358 Net carrying amounts $ 221,586,475 206,734,543 As of December 31, 2018 and 2019, a non-irrigated farmland located in LongTan plant amounted to $23,671 thousand was registered in the name of a farmer due to regulations. An agreement of pledge had been signed between the Company and the farmer clarifying the rights and obligations of each party. In order to enhance the utilization of the Company’s assets and to increase its working capital, AUSK disposed its land, plant buildings and related appendages to third party in December 2018 with consideration (net of costs of disposal) amounting to $3,029,191 thousand. The gain on disposal was amounting to $1,080,720 thousand. In 2017 and 2019, the Company wrote down certain machineries and equipment with extremely low utilization resulting from the decline in the application for certain products associated with its display segment and recognized an impairment loss of $895,954 thousand and $52,829 thousand, respectively. In 2017, 2018 and 2019, the Company wrote down certain long-term assets with extremely low capacity utilization associated with its energy segment and recognized impairment losses of $120,714 thousand, $399,363 thousand and $14,949 thousand, respectively. In 2019, ACTW has experienced significant fluctuations in its industry with oversupply capacity worldwide resulting in lower capacity utilization; therefore, the management performed impairment assessment of ACTW and its subsidiaries, as a CGU, over its long-term assets with recoverable amount determined based on the value in use. Based on the assessment performed as of December 31, 2019, the carrying amount of the CGU was determined to be higher than its estimated recoverable amount; consequently, an impairment loss of $2,232,739 thousand was recognized. Impairment losses as mentioned above were recognized as other gains and losses in the consolidated statements of comprehensive income. The estimated recoverable amount of 2019 was calculated by pre-tax discount rate of 10.63%. The following table summarized the Company’s capitalized borrowing costs and the interest rate range applied for the capitalization: For the years ended December 31, 2017 2018 2019 (in thousands) Capitalized borrowing costs $ 624,235 421,618 141,966 Interest rate range 1.09%~ 1.04%~ 1.07%~ 5.71% Certain property, plant and equipment were pledged as collateral, see note 44.

Lease Arrangements

Lease Arrangements	12 Months Ended
	Dec. 31, 2019
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Lease Arrangements	19. Lease Arrangements (a) Lessees (1) Right-of-use assets December 31, (in thousands) Carrying amount of right-of-use assets Land $ 11,595,815 Buildings 575,724 Other equipment 36,229 $ 12,207,768 For the year (in thousands) Additions to right-of-use assets $ 192,655 Depreciation charge for right-of-use assets Land $ 566,982 Buildings 238,969 Other equipment 66,590 $ 872,541 (2) Lease liabilities December 31, 2019 Future minimum lease payments Interests Present value of minimum lease payments (in thousands) Less than one year $ 879,518 197,151 682,367 Between one and five years 2,874,682 678,576 2,196,106 More than five years 9,588,087 1,375,483 8,212,604 $ 13,342,287 2,251,210 11,091,077 Lease liabilities － $ 682,367 Lease liabilities － $ 10,408,710 (3) Significant lease agreements AUO has entered into various land lease agreements with Hsinchu Science Park Bureau, Central Science Park Administration Bureau and Southern Taiwan Science Park Bureau, respectively, for the construction of plant for operations. All lease amounts are adjusted in accordance with the land value announced by the government from time to time. In 2019, AUO modified one of its lease contracts due to the decrease of the scope of the lease, and therefore, the carrying amount of the right-of-use asset was reduced by $1,064,094 thousand. The difference between the remeasurement of the lease liability and the reduction of the right-of-use asset was recognized in profit or loss. (4) Sublease of right-of-use assets The Company subleased part of its right-of-use assets under operating leases, in 2019, the income from sublease was $8,199 thousand. Right-of-use assets that meet the definition of investment properties are reclassified to investment properties. Refer to note 20 for further information on investment properties. (5) Additional lease information The Company applies the recognition exemption to account for short-term leases and leases of low-value assets, primarily for some leases of office buildings and other sporadic leasing. The amounts recognized in profit or loss during the lease term were as follows: For the year (in thousands) Expenses relating to short-term leases $ 15,832 Expenses relating to leases of low-value assets, excluding short-term leases of low-value assets $ 315 Total cash outflow for the Company’s leases in which it acts as a lessee for the year ended December 31, 2019 was $920,666 thousand. (b) Lessor The Company leased out its investment properties and part of its land, buildings and equipment and did not transfer substantially all the risks and rewards incidental to their ownership to the lessees, therefore, those leases were recognized as operating leases. Refer to note 34 for the information of rental income from operating leases. In addition, the direct costs relating to the aforementioned operating leases are amounting to $3,007 thousand for the year ended December 31, 2019. The maturity analysis of undiscounted operating lease receivable for the abovementioned assets are as follows: December 31, (in thousands) Year 1 $ 110,905 Year 2 110,316 Year 3 110,025 Year 4 106,272 Year 5 105,721 Year 6 onwards 2,079,849 Total undiscounted operating lease receivable $ 2,623,088 Refer to note 26 for the Company’s respective information as lessor and lessee as of December 31, 2018.

Investment Property

Investment Property	12 Months Ended
	Dec. 31, 2019
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Investment Property	20. Investment Property For the year ended December 31, 2018 Balance, Beginning Additions Reclassification and effect of change in exchange rate Balance, (in thousands) Land $ 717,823 - 12,483 730,306 Fair Value $ 2,213,184 2,252,170 For the year ended December 31, 2019 Balance, Beginning Additions Reclassification and effect of change in exchange rate Balance, (in thousands) Cost: Land $ 730,306 - (667 ) 729,639 Buildings - - 1,418,652 1,418,652 Right-of-use assets - - 28,570 28,570 730,306 - 1,446,555 2,176,861 Accumulated Depreciation: Buildings - 7,363 612,618 619,981 Right-of-use assets - 302 1,448 1,750 - 7,665 614,066 621,731 Net carrying amounts $ 730,306 1,555,130 Fair Value $ 2,252,170 4,057,848 In order to enhance the utilization of assets and to increase its working capital, AUSJ leased its buildings and right-of-use assets to third party in 2019, and has reclassified the aforementioned property, plant and equipment and right-of-use assets amounting to $832,886 thousand to investment property. The fair value of investment property is based on a valuation performed by a qualified independent appraiser who holds a recognized and relevant professional qualification and has recent valuation experience in the location and category of the investment property being valued. The valuation is performed using income approach, sales comparison approach and land development analysis approach with reference to available market information. The fair value measurement was categorized as a level 3 fair value based on the inputs in the valuation techniques used. Income approach determines the fair value of the investment property based on the projected cash flows from the Company’s estimated future rentals collected and discounted using the capitalization rate of the property. Sales comparison approach is through comparison, analysis, adjustment and other means of value for comparable properties to estimate the value of the investment property. Land development analysis approach determine the fair value of investment property based on the value prior to development or construction, after deducting the direct cost, indirect cost, capital interest and profit during the development period, and also consider total sales price of properties after completion of development or construction. It also incorporates the possibility of changes in utility of land through development or improvement in accordance with legal use and density of the land. The significant inputs used in the fair value measurement were as follows: December 31, 2018 2019 Overall capital interest rate 1.86 % 2.53 % Rate of return 10.00 % 15.00 % Capitalization rate 12.00 % 8.00%~12.00 % As of December 31, 2018 and 2019, there was no investment property that was pledged as collateral.

Intangible Assets

Intangible Assets	12 Months Ended
	Dec. 31, 2019
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Intangible Assets	21. Intangible Assets For the year ended December 31, 2018 Balance, Beginning Additions Effect of change in consolidated entities Effect of change in exchange rate Balance, End of Year (in thousands) Cost: Goodwill $ - - 600,324 - 600,324 Patent and technology fee 12,275,548 - - (3,806 ) 12,271,742 Others - - 150,436 - 150,436 12,275,548 - 750,760 (3,806 ) 13,022,502 Accumulated amortization: Patent and technology fee 10,385,251 518,404 - (386 ) 10,903,269 Others - 22,565 - - 22,565 10,385,251 540,969 - (386 ) 10,925,834 Net carrying amounts $ 1,890,297 2,096,668 For the year ended December 31, 2019 Balance, Beginning Additions Effect of change in exchange rate Balance, End of Year (in thousands) Cost: Goodwill $ 600,324 - - 600,324 Patent and technology fee 12,271,742 1,711 (7,140 ) 12,266,313 Others 150,436 - - 150,436 13,022,502 1,711 (7,140 ) 13,017,073 Accumulated amortization: Patent and technology fee 10,903,269 436,815 (1,178 ) 11,338,906 Others 22,565 127,871 - 150,436 10,925,834 564,686 (1,178 ) 11,489,342 Net carrying amounts $ 2,096,668 1,527,731 The Company acquired goodwill and other intangible assets arising from the business combination in March 2018. Please refer to note 15 for the relevant information. For the purpose of impairment test, the following table shows the information of the operating business that the Company’s goodwill allocating to. December 31, 2018 2019 (in thousands) Display business $ 600,324 600,324 The Company’s goodwill has been tested for impairment at least once at the end of the annual reporting period. The recoverable amount was determined based on value in use of the operating business. The key assumptions used in the estimation of the recoverable amount included discount rate and terminal growth rate. The annual discount rates for the years ended December 31, 2018 and 2019 were 11.57% and 12.25% respectively based on industry weighted average cost of capital. The cash flow projections were determined based on the financial budgets approved by management covering the future five-year period and extrapolated with a steady annual terminal growth rate for subsequent years, which were negative 1% and negative 0.5% for the years ended December 31, 2018 and 2019, respectively. The key assumptions abovementioned represents the management’s forecast of the future for the related industry by considering the history information from internal and external sources. Based on the impairment assessment for the years ended December 31, 2018 and 2019, no impairment losses were recognized as the recoverable amount of the CGU was higher than its carrying value.

Other Current Assets and Other

Other Current Assets and Other Noncurrent Assets	12 Months Ended
	Dec. 31, 2019
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Other Current Assets and Other Noncurrent Assets	22. Other Current Assets and Other Noncurrent Assets December 31, 2018 2019 (in thousands) Refundable and overpaid tax $ 1,351,646 1,458,170 Refundable deposits 716,097 663,911 Prepayment for equipment 650,727 453,300 Prepayments for purchases 230,793 158,521 Long-term receivables 930,001 5,812 Long-term prepaid rents 1,364,111 - Others 2,869,869 2,961,194 8,113,244 5,700,908 Less: current (2,941,598 ) (3,295,562 ) Noncurrent $ 5,171,646 2,405,346 The long-term prepaid rents were reclassified to right-of-use assets on January 1, 2019 upon the initial adoption of IFRS 16. See note 4(a).

Short-term Borrowings

Short-term Borrowings	12 Months Ended
	Dec. 31, 2019
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Short-term Borrowings	23. Short-term Borrowings December 31, 2018 2019 (in thousands) Unsecured borrowings $ 546,472 1,725,602 Unused credit facilities $ 43,533,037 37,982,721 Interest rate range 2.54%~ 1.20%~

Long-term Borrowings

Long-term Borrowings	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Long-term Borrowings	24. Long-term Borrowings Bank or agent bank Durations December 31, 2018 December 31, 2019 (in thousands) Syndicated loans: Bank of Taiwan and others From Feb. 2019 to Feb. 2024 $ - 42,000,000 Bank of Taiwan and others From Mar. 2019 to Apr. 2023 - 23,000,000 Bank of Taiwan and others From May 2017 to May 2022 10,000,000 10,000,000 Bank of Taiwan and others From Apr. 2016 to Apr. 2019 36,175,000 - Bank of Taiwan and others From Feb. 2015 to Feb. 2019 5,912,000 - Bank of Taiwan and others From Jul. 2018 to Oct. 2019 210,000 - First Commercial Bank and others From Feb. 2016 to Jan. 2019 1,775,236 - Bank of China and others From Nov. 2015 to Nov. 2023 27,743,519 21,500,826 Unsecured loans From Apr. 2017 to Aug. 2023 2,976,158 8,050,310 Secured loans From Apr. 2017 to Apr. 2032 1,990,175 7,671,932 86,782,088 112,223,068 Less: transaction costs (476,770 ) (254,676 ) 86,305,318 111,968,392 Less: current portion (29,595,931 ) (9,535,198 ) $ 56,709,387 102,433,194 Unused credit facilities $ 79,933,812 32,265,575 Interest rate range 1.07%~ 1.00%~ The Company entered into the aforementioned long-term loan arrangements with banks and financial institutions to finance capital expenditures for purchase of machinery and equipment, and to fulfill working capital, as well as to repay the matured debts. A commitment fee is negotiated with the leading banks of syndicated loans, and is calculated based on the committed-to-withdraw but unused balance, if any. No commitment fees were paid for the year ended December 31, 2019. These credit facilities contain covenants that require the Company to maintain certain financial ratios, calculating based on the Company’s annual consolidated financial statements prepared in accordance with Taiwan Financial Reporting Standards, such as current ratio (defined as current assets divided by current liabilities excluding current portion of long-term debt and payable for equipment and construction), leverage ratio (calculated as the sum of short-term borrowings plus current portion of long-term debt and long-term debt to consolidated tangible net worth), interest coverage ratio, tangible net worth and others as specified in the loan agreements. As of December 31, 2018 and 2019, the Company complied with all financial covenants required under each of the loan agreements. Refer to note 41 for detailed information of exposures to interest rate, currency, and liquidity risks. Refer to note 44 for assets pledged as collateral to secure the aforementioned long-term borrowings.

Provisions

Provisions	12 Months Ended
	Dec. 31, 2019
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Provisions	25. Provisions Warranties (i) Litigation and claims Others Total (in thousands) Balance at January 1, 2018 $ 1,546,960 89,520 249,483 1,885,963 Additions 276,846 336,061 571,113 1,184,020 Usage (259,109 ) - (187,842 ) (446,951 ) Reversals (100,754 ) - (215 ) (100,969 ) Effect of change in exchange rate (74 ) 5,647 10,413 15,986 Balance at December 31, 2018 1,463,869 431,228 642,952 2,538,049 Less: current (686,424 ) (431,228 ) (389,912 ) (1,507,564 ) Noncurrent $ 777,445 - 253,040 1,030,485 Balance at January 1, 2019 $ 1,463,869 431,228 642,952 2,538,049 Additions 554,935 - 11,800 566,735 Usage (422,976 ) (156,521 ) (63,661 ) (643,158 ) Reversals (303,423 ) (116,094 ) (264,008 ) (683,525 ) Effect of change in exchange rate (159 ) (6,312 ) (10,072 ) (16,543 ) Balance at December 31, 2019 1,292,246 152,301 317,011 1,761,558 Less: current (486,517 ) (152,301 ) (69,450 ) (708,268 ) Noncurrent $ 805,729 - 247,561 1,053,290 (i) The provisions for warranties were estimated based on historical experience of warranty claims rate associated with similar products and services. The Company expects most warranty claims will be made within two years from the date of the sale of the product.

Operating Leases

Operating Leases	12 Months Ended
	Dec. 31, 2019
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Operating Leases	26. Operating Leases (a) Lessees Future minimum lease payments under non-cancellable operating leases as of December 31, 2018 was as follows: December 31, 2018 (in thousands) Less than one year $ 927,351 Between one and five years 2,928,983 More than five years 2,085,877 $ 5,942,211 AUO entered into various operating lease agreements for land with Hsinchu Science Park Bureau beginning from March 1, 1994 for a period of 20 years, with renewal option upon expiration. AUO had on July 2003 and November 2006, entered into various operating lease for land with Central Science Park Administration Bureau for period from July 28, 2003 till December 31, 2023 and November 9, 2006 till December 31, 2025. All lease amounts are adjusted in accordance with the land value announced by the government from time to time. AUO had also on February 2008 and October 2018, respectively, renewed its lease agreements with Hsinchu Science Park Bureau and Southern Taiwan Science Park Bureau, respectively, Rental expense for operating leases amounted to $1,081,731 thousand and $1,064,263 thousand for the years ended December 31, 2017 and 2018, respectively. (b) Lessor The Company leased its investment properties to third parties under operating lease. Refer to note 20 for further information on investment properties. Future minimum lease receivables under non-cancellable operating leases as of December 31, 2018 was as follows: December 31, 2018 (in thousands) Less than one year $ 105,788 Between one and five years 423,150 More than five years 2,188,728 $ 2,717,666 In addition to the above-mentioned, the Company also leased partial offices to others. See note 34 for rental income. Repair and maintenance expenses incurred from aforementioned operating leases for the years ended December 31, 2017 and 2018 amounted to $18,396 thousand and $1,723 thousand, respectively.

Employee Benefits

Employee Benefits	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Employee Benefits	27. Employee Benefits (a) Defined benefit plans Pursuant to the ROC Labor Standards Act, AUO has established a defined benefit pension plan covering their full-time employees in the ROC. This plan provides for retirement benefits to retiring employees based on years of service and the average salaries and wages for the six-month period before the employee’s retirement. The funding of this retirement plan by AUO is contributed monthly based on a certain percentage of employees’ total salaries and wages. The fund is deposited with Bank of Taiwan. M.Setek has established defined benefit pension plans providing for retirement benefits to retiring employees based on years of service, position, and certain other factors in accordance with the regulations of its country of establishment. (1) Reconciliation for AUO’s and M.Setek’s present value of defined benefit obligation and the fair value of plan assets December 31, 2018 2019 (in thousands) Present value of defined benefit obligation $ (3,257,962 ) (3,155,988 ) Fair value of plan assets 2,367,273 2,542,831 Net defined benefit liability $ (890,689 ) (613,157 ) (2) Movement in net defined benefit asset (liability) Defined benefit obligation Fair value of plan assets Net defined benefit asset (liability) 2018 2019 2018 2019 2018 2019 (in thousands) Balance at January 1, $ (3,128,927 ) (3,257,962 ) 2,213,018 2,367,273 (915,909 ) (890,689 ) Included in profit or loss Service cost (5,289 ) (4,104 ) - - (5,289 ) (4,104 ) Interest cost (49,598 ) (39,337 ) - - (49,598 ) (39,337 ) Expected return on plan assets - - 35,408 28,880 35,408 28,880 (54,887 ) (43,441 ) 35,408 28,880 (19,479 ) (14,561 ) Included in other comprehensive income Remeasurements (loss) gain: Actuarial (loss) gain arising from: - demographic assumptions (15,795 ) 89,851 - - (15,795 ) 89,851 - financial assumptions (178,212 ) (206,995 ) - - (178,212 ) (206,995 ) - experience adjustment 84,437 228,466 - - 84,437 228,466 Return on plan assets excluding interest income - - 52,614 76,788 52,614 76,788 (109,570 ) 111,322 52,614 76,788 (56,956 ) 188,110 Other Contributions paid by the employer - - 102,831 101,019 102,831 101,019 Benefits paid 36,915 33,936 (36,598 ) (31,129 ) 317 2,807 Effect of changes in exchange rates and others (1,493 ) 157 - - (1,493 ) 157 35,422 34,093 66,233 69,890 101,655 103,983 Balance at December 31, $ (3,257,962 ) (3,155,988 ) 2,367,273 2,542,831 (890,689 ) (613,157 ) (3) Plan assets Pursuant to the ROC Labor Standards Act, AUO contributes an amount based on a certain percentage of employees’ total salaries and wages paid every month to its pension fund (the “Fund”), which is administered by the Bureau of Labor Fund, Ministry of Labor and supervised by the employees’ pension plan committee (the “Committee”) and deposited in the Committee’s name with Bank of Taiwan. Under the ROC Regulations for Revenues, Expenditures, Safeguard and Utilization of the Labor Retirement Fund, the minimum return on the plan assets should not be lower than the average interest rate on two-year time deposits published by the local banks. The government is not only responsible for the determination of the investment strategies and policies, but also for any shortfall in the event that the rate of return is less than the required rate of return. As of December 31, 2019, the Fund deposited in the Committee’s name in the Bank of Taiwan amounted to $2,542,854 thousand. Information on utilization of labor pension funds, including the yield rate of funds and the component of plan assets are available at the Bureau of Labor Funds, Ministry of Labor website. Under the defined benefit plans in Japan, M.Setek is responsible to pay to employees when they are retired. (4) Defined benefit obligation (i) Principal actuarial assumptions December 31, 2018 2019 Discount rate 0.21%~1.22% 0.18%~0.88% Rate of increase in future salary 0.77%~4.49% 0.77%~4.49% The Company anticipates contributing $100,799 thousand to the defined benefit plans in the next year starting from January 1, 2020. As at December 31, 2019, the weighted-average duration of the defined benefit obligation was between 5 years to 20 years. (ii) Sensitivity analysis Reasonably possible changes at December 31, 2018 and 2019 to one of the relevant actuarial assumptions, holding other assumptions constant, would have affected the defined benefit obligation by the amounts shown below. December 31, 2018 December 31, 2019 Changes in assumptions Changes in assumptions + 0.25% - 0.25% + 0.25% - 0.25% (in thousands) (in thousands) Discount rate $ (160,307 ) 169,544 (150,970 ) 159,425 Rate of increase in future salary $ 166,250 (158,100 ) 156,774 (148,385 ) In practical, the relevant actuarial assumptions are correlated to each other. The approach to develop the sensitivity analysis as above is the same approach to recognize the net defined benefit liability in the statement of financial position. The approach to develop the sensitivity analysis and its relevant actuarial assumptions are the same as those in previous year. (b) Defined contribution plans Commencing July 1, 2005, pursuant to the ROC Labor Pension Act (the “Act”), employees who elected to participate in the Act or joined the Company after July 1, 2005, are subject to a defined contribution plan under the Act. Under the defined contribution plan, AUO and its subsidiaries located in the ROC contribute monthly at a rate of no less than six percent of the employees’ monthly salaries and wages to the employee’s individual pension fund account at the ROC Bureau of Labor Insurance. The Company’s foreign subsidiaries have set up their retirement plans, if necessary, based on their respective local government regulations. AUO and its subsidiaries in the ROC have set up defined contribution plans in accordance with the Act. For the years ended December 31, 2017, 2018 and 2019, these companies set aside $1,003,063 thousand, $1,024,700 thousand and $977,908 thousand, respectively, of the pension costs under the pension plan to the ROC Bureau of the Labour Insurance. Except for the aforementioned companies, other foreign subsidiaries recognized pension expenses of $892,109 thousand, $923,378 thousand and $784,169 thousand for the years ended December 31, 2017, 2018 and 2019, respectively, for the defined contribution plans based on their respective local government regulations.

Capital and Other Components of

Capital and Other Components of Equity	12 Months Ended
	Dec. 31, 2019
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Capital and Other Components of Equity	28. Capital and Other Components of Equity (a) Common stock AUO’s authorized common stock, with par value of $10 per share, both amounted to $100,000,000 thousand as at December 31, 2018 and 2019. AUO’s issued common stock, with par value of $10 per share, both amounted to $96,242,451 thousand as at December 31, 2018 and 2019. On September 9, 2019, AUO's Board of Directors approved the delisting of ADSs from the NYSE and trading on the OTC market. On and from October 1, 2019, AUO's ADSs has begun trading on the OTC market. As of December 31, 2019, AUO has issued 50,123 thousand ADSs, which represented 501,229 thousand shares of its common stock. (b) Capital surplus The components of capital surplus as of December 31, 2018 and 2019 were as follows: December 31, 2018 2019 (in thousands) From common stock $ 52,756,091 52,756,091 From convertible bonds 6,049,862 6,049,862 From others 1,814,271 1,737,730 $ 60,620,224 60,543,683 According to the ROC Company Act, capital surplus, including premium from stock issuing and donations received, shall be applied to offset accumulated deficits before it can be distributed by issuing common stock as stock dividends or by cash according to the proportion of shareholdings. Pursuant to the ROC Regulations Governing the Offering and Issuance of Securities by Securities Issuers, the total sum of capital surplus capitalized per annum shall not exceed 10 percent of the paid-in capital. (c) Legal reserve According to the ROC Company Act, 10 percent of the net profit shall be allocated as legal reserve until the accumulated legal reserve equals the paid-in capital. When a company incurs no loss, it may, pursuant to a resolution to be adopted by a shareholders’ meeting, distribute its legal reserve by issuing new shares or by cash, only the portion of legal reserve which exceeds 25 percent of the paid-in capital may be distributed. (d) Distribution of earnings and dividend policy In accordance with AUO’s Articles of Incorporation, after payment of income taxes and offsetting accumulated deficits, the legal reserve shall be set aside until the accumulated legal reserve equals AUO’s paid-in capital. In addition, a special reserve in accordance with applicable laws and regulations shall also be set aside or reversed. The remaining current-year earnings together with accumulated undistributed earnings from preceding years can be distributed according to relevant laws and AUO’s Articles of Incorporation. AUO ’s dividend policy is to pay dividends from surplus considering factors such as AUO current and future investment environment, cash requirements, domestic and overseas competitive conditions and capital budget requirements, while taking into account shareholders interest, maintenance of balanced dividend and AUO s long-term financial plan. If the current-year retained earnings available for distribution reach 2% of the paid-in capital of AUO, dividend to be distributed shall be no less than 20% of the current-year retained earnings available for distribution. If the current-year retained earnings available for distribution do not reach 2% of the paid-in capital of AUO, AUO may decide not to distribute dividend. The cash portion of the dividend, which may be in the form of cash and stock, shall not be less than 10% of the total dividend distributed during the year. The dividend distribution ratio aforementioned could be adjusted after taking into consideration factors such as finance, business and operations, etc. Pursuant to relevant laws or regulations or as requested by the local authority, total net debit balance of the other components of equity shall be set aside from current earnings as special reserve, and not for distribution. Subsequent decrease pertaining to items that are accounted for as a reduction to the other components of equity shall be reclassified from special reserve to undistributed earnings. AUO’s appropriations of earnings for 2017 had been approved in the shareholders’ meeting held on June 15, 2018. The appropriations and dividends per share were as follows: For fiscal year 2017 Appropriation of earnings Dividends per share (in thousands, except for per share data) Legal reserve $ 3,235,942 Cash dividends to shareholders 14,436,368 $ 1.50 $ 17,672,310 The aforementioned appropriation of earnings for 2017 was consistent with the resolutions of the board of directors’ meeting held on March 23, 2018. AUO’s appropriations of earnings for 2018 had been approved in the shareholders’ meeting held on June 14, 2019. The appropriations and dividends per share were as follows: For fiscal year 2018 Appropriation of earnings Dividends per share (in thousands, except for per share data) Legal reserve $ 1,016,060 Special reserve 847,770 Cash dividends to shareholders 4,812,122 $ 0.50 $ 6,675,952 The aforementioned appropriation of earnings for 2018 was consistent with the resolutions of the board of directors’ meeting held on March 22, 2019. In addition, on March 20, 2020, AUO’s board of directors proposed not to distribute any dividend for 2019. However, the appropriation will be subject to the resolution of AUO’s annual shareholders’ meeting in 2020. Information on the approval of board of directors and shareholders for AUO’s appropriations of earnings are available at the Market Observation Post System website. (e) Treasury shares According to the resolution approved by the board of directors’ meeting held on September 9, 2019, AUO expects to repurchase 125,000 thousand shares as treasury shares transferred to employees in accordance with the Securities and Exchange Act requirements. The related information on treasury share transactions was as follows: Year Ended December 31, 2019 Reason for Number of shares, Beginning of Year Additions Reductions Number of shares, (in thousands of shares) Transferring to employees - 125,000 - 125,000 Pursuant to the Securities and Exchange Act, the number of shares repurchased shall not exceed 10 percent of the number of the company’s issued and outstanding shares, and the total amount repurchased shall not exceed the sum of the company’s retained earnings, share premium, and realized capital surplus. Also, the shares repurchased for transferring to employees shall be transferred within five years from the date of reacquisition and those shares not transferred within the five-year period are to be retired. In accordance with the Securities and Exchange Act, treasury shares held by AUO shall not be pledged, and do not hold any shareholder rights before their transfer. (f) Other components of equity Cumulative translation differences Unrealized gains (losses) on available-for-sale financial Unrealized gains (losses) on cash flow hedges Total (in thousands) Balance at January 1, 2017 $ 531,006 224,299 21,992 777,297 Foreign operations – foreign currency translation differences (1,882,545 ) - - (1,882,545 ) Effective portion of changes in fair value of cash flow hedges - - (21,992 ) (21,992 ) Net change in fair value of available-for-sale financial assets - 1,146,422 - 1,146,422 Equity-accounted investees – share of other comprehensive income (68,637 ) 6,310 - (62,327 ) Related tax 299,207 - - 299,207 Balance at December 31, 2017 $ (1,120,969 ) 1,377,031 - 256,062 Cumulative translation differences Unrealized gains (losses) on financial Unrealized gains (losses) on available-for-sale financial Total (in thousands) Balance at January 1, 2018 $ (1,120,969 ) - 1,377,031 256,062 Adjustments on initial application of new standards - 1,303,816 (1,377,031 ) (73,215 ) Foreign operations – foreign currency translation differences (336,902 ) - - (336,902 ) Net change in fair value of financial assets at FVTOCI - (754,813 ) - (754,813 ) Equity-accounted investees – share of other comprehensive income (19,716 ) 3,053 - (16,663 ) Realized gain on sales of securities reclassified to profit or loss (107,457 ) - - (107,457 ) Cumulative unrealized loss of equity instruments transferred to retained earnings due to disposal - 50,084 - 50,084 Group reorganization (22,225 ) - - (22,225 ) Related tax 157,359 - - 157,359 Balance at December 31, 2018 $ (1,449,910 ) 602,140 - (847,770 ) Cumulative translation differences Unrealized gains (losses) on financial Total (in thousands) Balance at January 1, 2019 $ (1,449,910 ) 602,140 (847,770 ) Foreign operations – foreign currency translation differences (2,043,931 ) - (2,043,931 ) Net change in fair value of financial assets at FVTOCI - 519,100 519,100 Equity-accounted investees – share of other comprehensive income (38,512 ) 3,358 (35,154 ) Realized gain on sales of securities reclassified to profit or loss (9,098 ) - (9,098 ) Related tax 411,469 - 411,469 Balance at December 31, 2019 $ (3,129,982 ) 1,124,598 (2,005,384 ) (g) Non-controlling interests, net of tax For the years ended December 31, 2017 2018 2019 (in thousands) Balance at the beginning of the year $ 18,388,204 17,068,501 14,416,559 Equity attributable to non-controlling interests: 　Loss for the year (2,120,737 ) (2,177,869 ) (2,413,718 ) 　Adjustment of changes in ownership of investees (6,421 ) (20,998 ) 110,028 　Foreign currency translation differences (355,700 ) (306,963 ) (404,575 ) 　Unrealized losses on financial assets at FVTOCI - (1,474 ) - 　Remeasurement of defined benefit plans 201 - - 　Effect of disposal of interest in subsidiary to non-controlling interests 1,258,788 - - 　Effect of acquisition of non-controlling interests - - (389,430 ) 　Proceeds from subsidiaries capital increase and others (95,834 ) (144,638 ) (13,957 ) Balance at the end of the year $ 17,068,501 14,416,559 11,304,907

Share-based Payments

Share-based Payments	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Share-based Payments	29. Share-based Payments The Company’s employee stock option plans were as follows: (a) DPTW Option Plan DPTW 2011 Employee stock option plan was fully expired on January 6, 2017. Information about DPTW’s outstanding stock options is as follows: For the year ended Weighted-average exercise price Number of options (shares) Outstanding at January 1 $ 19.04 2,913,000 Options expired - (2,913,000 ) Outstanding at December 31 - - Exercisable at December 31 - (b) ACTW Option Plan (1) The key terms and conditions related to the grants under ACTW’s outstanding employee stock option plan were disclosed as follows: Grant date Total number of options issued (units in thousands) Contractual life of options Exercisable period Exercise price 2014 Employee stock option plan Sep. 1, 2014 20 Sep.1, 2014 – Aug. 31, 2019 After Aug. 31, 2016 $10 ACTW 2012 Employee stock option plan was fully expired on August 31, 2017. (2) The related employee benefit expenses and capital surplus recognized on ACTW’s employee stock options were $474 thousand, $167 thousand and $0 for the years ended December 31, 2017, 2018 and 2019, respectively. (3) Fair value of stock options The fair value of the employee stock options granted by ACTW was measured at the dates of grant using the Binomial option pricing model. The valuation information was as follows: 2014 Employee Stock Option Plan Expected volatility 38.88% Risk-free interest rate 1.1648% Expected duration 5 years Fair value at the grant date NT$0.20/per share (4) Information about ACTW’s outstanding stock options is as follows: For the years ended December 31, 2018 2019 Weighted-average exercise price Number of options (shares) Weighted-average exercise price Number of options (shares) Outstanding at January 1 $ 10 16,601,000 $ 10 13,291,000 Options exercised 10 (2,260,000 ) 10 (11,995,000 ) Options expired - (1,050,000 ) - (1,296,000 ) Outstanding at December 31 10 13,291,000 - - Exercisable at December 31 13,291,000 -

Revenue from Contracts with Cus

Revenue from Contracts with Customers	12 Months Ended
	Dec. 31, 2019
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Revenue from Contracts with Customers	30. Revenue from Contracts with Customers For the year ended December 31, 2018 Display segment Energy segment Total segments (in thousands) Primary geographical markets: PRC $ 112,542,529 1,089,508 113,632,037 Taiwan 93,126,115 6,231,767 99,357,882 Singapore 39,363,415 7,515 39,370,930 Japan 19,748,373 1,418,491 21,166,864 Others 26,004,322 8,102,354 34,106,676 $ 290,784,754 16,849,635 307,634,389 For the year ended December 31, 2018 Display segment Energy segment Total segments (in thousands) Major products: Products for Televisions $ 113,194,567 - 113,194,567 Products for Mobile PCs and Devices 74,375,305 - 74,375,305 Products for Monitors 47,024,353 - 47,024,353 Products for Commercial and Others (i) 56,190,529 - 56,190,529 Solar Products - 16,849,635 16,849,635 $ 290,784,754 16,849,635 307,634,389 Major customers: Customer A $ 35,358,013 - 35,358,013 Others (individually not greater than 10%) 255,426,741 16,849,635 272,276,376 $ 290,784,754 16,849,635 307,634,389 For the year ended December 31, 2019 Display segment Energy segment Total segments (in thousands) Primary geographical markets: PRC $ 97,084,436 1,277,799 98,362,235 Taiwan 78,394,325 4,835,269 83,229,594 Singapore 38,526,625 7,666 38,534,291 Japan 19,877,671 1,046,332 20,924,003 Others 22,784,165 4,957,406 27,741,571 $ 256,667,222 12,124,472 268,791,694 Major products: Products for Televisions $ 87,269,763 - 87,269,763 Products for Mobile PCs and Devices 69,305,510 - 69,305,510 Products for Monitors 39,522,268 - 39,522,268 Products for Commercial and Others (i) 60,569,681 - 60,569,681 Solar Products - 12,124,472 12,124,472 $ 256,667,222 12,124,472 268,791,694 Major customers: Customer A $ 33,142,985 - 33,142,985 Others (individually not greater than 10%) 223,524,237 12,124,472 235,648,709 $ 256,667,222 12,124,472 268,791,694 (i) Others include sales from products for other applications and sales of raw materials, components and from service charges. Refer to note 31 and note 46 for revenue related information for the year ended December 31, 2017.

Revenue

Revenue	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Revenue	31. Revenue For the year ended December 31, 2017 (in thousands) Sale of goods $ 329,584,136 Other operating revenue 11,444,131 $ 341,028,267 Refer to note 30 for the disaggregation of revenue for the years ended December 31, 2018 and 2019.

Remuneration to Employees and D

Remuneration to Employees and Directors	12 Months Ended
	Dec. 31, 2019
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Remuneration to Employees and Directors	32. Remuneration to Employees and Directors According to AUO’s Articles of Incorporation, AUO should distribute remuneration to employees and directors no less than 5% and no more than 1% of annual profits before income tax, respectively, after offsetting accumulated deficits, if any. Only employees, including employees of affiliate companies that meet certain conditions are entitled to the abovementioned remuneration which to be distributed in stock or cash. The said conditions and distribution method are decided by board of directors or the personnel authorized by board of directors. AUO did not accrue remuneration to employees and directors due to the loss making position for the year ended December 31, 2019. AUO accrued remuneration to employees based on the profit before income tax excluding the remuneration to employees and directors for the period, multiplied by the percentage resolved by board of directors. For the years ended December 31, 2017 and 2018, AUO estimated the remuneration to employees amounting to $4,062,114 thousand and $1,215,696 thousand, respectively. Remuneration to directors was estimated based on the amount expected to pay and recognized together with the remuneration to employees as cost of sales or operating related expenses. If remuneration to employees is resolved to be distributed in stock, the number of shares is determined by dividing the amount of remuneration by the closing price of the shares (ignoring ex-dividend effect) on the day preceding the board of directors’ meeting. If there is a change in the proposed amounts after the annual consolidated financial statements are authorized for issue, the differences are accounted for as a change in accounting estimate and adjusted prospectively to next year’s profit or loss. Remuneration to employees and directors for 2017 in the amounts of $4,062,114 thousand and $132,604 thousand, respectively, in cash for payment had been approved in the meeting of board of directors held on March 23, 2018. The aforementioned approved amounts are the same as the amounts charged against earnings of 2017. Remuneration to employees and directors for 2018 in the amounts of $1,215,696 thousand and $27,780 thousand, respectively, in cash for payment have been approved in the meeting of board of directors held on March 22, 2019. The aforementioned approved amounts are the same as the amounts charged against earnings of 2018. The information about AUO’s remuneration to employees and directors is available at the Market Observation Post System website.

The Nature of Expenses

The Nature of Expenses	12 Months Ended
	Dec. 31, 2019
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The Nature of Expenses	33. The Nature of Expenses (a) Depreciation of property, plant and equipment For the years ended December 31, 2017 2018 2019 (in thousands) Recognized in cost of sales $ 31,660,279 29,980,415 31,599,910 Recognized in operating expenses (i) 4,140,951 3,706,146 4,093,123 $ 35,801,230 33,686,561 35,693,033 (b) Amortization of intangible assets For the years ended December 31, 2017 2018 2019 (in thousands) Recognized in cost of sales $ 628,606 518,403 436,815 Recognized in operating expenses (i) - 22,566 127,871 $ 628,606 540,969 564,686 (c) Employee benefits expenses For the years ended December 31, 2017 2018 2019 (in thousands) Salaries and wages $ 37,818,321 34,933,925 30,824,887 Labor and health insurances 1,967,688 2,009,652 1,917,244 Retirement benefits 1,917,136 1,967,557 1,776,638 Other employee benefits 3,197,324 3,839,988 3,635,371 $ 44,900,469 42,751,122 38,154,140 Employee benefits expense summarized by function Recognized in cost of sales $ 34,703,579 33,455,273 29,453,257 Recognized in operating expenses (i) 10,196,890 9,295,849 8,700,883 $ 44,900,469 42,751,122 38,154,140 (i) Operating expenses are inclusive of selling and distribution expenses, general and administrative expenses and research and development expenses.

Other Income

Other Income	12 Months Ended
	Dec. 31, 2019
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Other Income	34. Other Income For the years ended December 31, 2017 2018 2019 (in thousands) Interest income on bank deposits $ 591,995 832,621 879,053 Interest income on government bonds with reverse repurchase agreements and others 20,215 8,994 6,467 Rental income, net 531,442 628,401 488,811 Dividend income 248,514 468,263 295,575 Grants 1,801,585 2,716,197 2,734,987 Others 636,146 757,649 915,378 $ 3,829,897 5,412,125 5,320,271

Other Gains and Losses

Other Gains and Losses	12 Months Ended
	Dec. 31, 2019
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Other Gains and Losses	35. Other Gains and Losses For the years ended December 31, 2017 2018 2019 (in thousands) Foreign exchange gains (losses), net $ (1,364,929 ) (41,391 ) (168,499 ) Gains on valuation of financial instruments at FVTPL, net 1,646,034 507,532 381,620 Gains (losses) on disposals of investments and financial assets, net 42,788 - (13,154 ) Gains on disposals of property, plant and equipment, net 330,814 1,923,044 106,546 Impairment losses on assets (1,046,668 ) (399,363 ) (2,298,646 ) Gains (losses) from litigation and others (584,599 ) (501,770 ) 396,519 $ (976,560 ) 1,488,052 (1,595,614 )

Finance Costs

Finance Costs	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Finance Costs	36. Finance Costs For the years ended December 31, 2017 2018 2019 (in thousands) Interest expense on bank borrowings $ 2,519,839 2,442,872 2,714,080 Interest expense on lease liabilities - - 209,607 Interest expense on others 348,022 220,733 327,683 $ 2,867,861 2,663,605 3,251,370

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Income Taxes	37. Income Taxes According to the amendment to the ROC Income Tax Act enacted on February 7, 2018, an increase in the corporate income tax rate from 17% to 20% is applicable to AUO and its domestic subsidiaries starting from fiscal year 2018 and beyond. In addition, the tax rate for 2018 undistributed earnings was reduced from 10% to 5%. The Company cannot file a consolidated tax return under local regulations. Therefore, AUO and its subsidiaries calculate their income taxes liabilities individually on a stand-alone basis using the enacted tax rates in their respective tax jurisdictions. (a) The components of income tax expense (benefit) for the years ended December 31, 2017, 2018 and 2019 were as follows: For the years ended December 31, 2017 2018 2019 (in thousands) Current income tax expense (benefit): Current year $ 3,719,483 1,444,698 752,863 Adjustment to prior years and others 246,264 (1,772,898 ) (684,197 ) 3,965,747 (328,200 ) 68,666 Deferred tax expense (benefit): Temporary differences (1,271,415 ) (632,785 ) 584,559 Investment tax credit and tax losses carryforwards (3,819,489 ) 1,998,662 682,930 Effect of changes in statutory income tax rate - (715,303 ) - (5,090,904 ) 650,574 1,267,489 Total income tax expense (benefit) $ (1,125,157 ) 322,374 1,336,155 (b) Income taxes expense (benefit) recognized directly in other comprehensive income for the years ended December 31, 2017, 2018 and 2019 were as follows: For the years ended December 31, 2017 2018 2019 (in thousands) Items that will never be reclassified to profit or loss: Remeasurement of defined benefit obligations $ (155,930 ) (38,908 ) 37,622 Items that are or may be reclassified subsequently to profit or loss: Foreign operations – foreign currency translation differences $ (316,372 ) (191,809 ) (459,729 ) (c) Reconciliation of the expected income tax expense (benefit) calculated based on the ROC statutory income tax rate compared with the actual income tax expense (benefit) as reported in the consolidated statements of comprehensive income for the years ended December 31, 2017, 2018 and 2019, was as follows: For the years ended December 31 2017 2018 2019 (in thousands) Profit (Loss) before income taxes $ 39,363,606 11,216,151 (19,844,754 ) Income tax expense at AUO’s statutory tax rate 6,691,813 2,243,230 (3,968,951 ) Effect of different subsidiaries income tax rate 348,192 (484,055 ) 38,756 Share of profit (loss) of equity-accounted subsidiaries (708,417 ) 795,459 (73,968 ) Effect of changes in statutory income tax rate - (715,303 ) - Effect of change of unrecognized deductible temporary differences, tax losses carryforwards, and investment tax credits (10,645,339 ) 138,969 5,947,778 Net of non-taxable income and non-deductible expense 698,540 (186,957 ) 265,119 Tax on undistributed earnings, net 2,987,763 323,559 7,709 Adjustments to prior year (528,662 ) (1,772,898 ) (684,197 ) Others 30,953 (19,630 ) (196,091 ) Income tax expense (benefit) $ (1,125,157 ) 322,374 1,336,155 Effective tax rate (2.85 )% 2.87 % (6.73 )% The above reconciliation is prepared based on each individual entity of the Company and presented on an aggregate basis. During the year ended December 31, 2017, the Company has utilized previously unrecognized tax losses carryforwards in current year amounting to $7,494,191 thousand and recognized deferred tax assets arising from tax losses carryforwards of $3,878,233 thousand that are expected to be utilized in future periods. (d) The components of deferred tax assets and liabilities were as follows: Deferred tax assets Deferred tax liabilities Total December 31, 2018 December 31, 2019 December 31, 2018 December 31, 2019 December 31, 2018 December 31, 2019 (in thousands) Investment tax credits $ 542,115 385,728 - - 542,115 385,728 Tax losses carryforwards 2,760,163 2,223,440 - - 2,760,163 2,223,440 Unrealized loss and expenses 310,192 166,393 (5,556 ) (5,321 ) 304,636 161,072 Inventories write-down 1,027,680 879,267 - - 1,027,680 879,267 Foreign investment gains under the equity method - - (1,049,091 ) (1,043,486 ) (1,049,091 ) (1,043,486 ) Remeasurement of defined benefit plans 194,838 157,216 - - 194,838 157,216 Foreign operations – foreign currency translation differences 426,333 886,062 - - 426,333 886,062 Others 1,371,347 483,511 (577,517 ) (1,864 ) 793,830 481,647 Deferred tax assets (liabilities) $ 6,632,668 5,181,617 (1,632,164 ) (1,050,671 ) 5,000,504 4,130,946 (e) Changes in deferred tax assets and liabilities were as follows: January 1, 2018 Recognized Recognized Effect of change in consolidated entities, December Recognized Recognized Effect of change in consolidated entities, December (in thousands) Investment tax credits $ 656,480 (132,840 ) - 18,475 542,115 (148,453 ) - (7,934 ) 385,728 Tax losses carryforwards 3,942,012 (1,181,429 ) - (420 ) 2,760,163 (534,477 ) - (2,246 ) 2,223,440 Unrealized loss and expenses 222,739 81,893 - 4 304,636 (143,534 ) - (30 ) 161,072 Inventories write-down 644,887 386,558 - (3,765 ) 1,027,680 (148,035 ) - (378 ) 879,267 Foreign investment losses (gains) under the equity method (890,153 ) (158,938 ) - - (1,049,091 ) 5,605 - - (1,043,486 ) Remeasurement of defined benefit plans 155,930 - 38,908 - 194,838 - (37,622 ) - 157,216 Foreign operations – foreign currency translation differences 234,524 - 191,809 - 426,333 - 459,729 - 886,062 Others 464,368 354,182 - (24,720 ) 793,830 (298,595 ) - (13,588 ) 481,647 Total $ 5,430,787 (650,574 ) 230,717 (10,426 ) 5,000,504 (1,267,489 ) 422,107 (24,176 ) 4,130,946 (f) Unrecognized deferred tax assets and unrecognized deferred tax liabilities Deferred tax assets have not been recognized in respect of the following items. December 31, 2018 2019 (in thousands) Unused tax losses carryforwards $ 28,697,671 32,445,130 Unused investment tax credits 853,837 981,360 Difference in depreciation expense for tax and financial purposes 1,972,536 1,866,430 Inventories write-down 19,852 22,875 Others 646,390 1,730,739 $ 32,190,286 37,046,534 As of December 31, 2019, the unused investment tax credits include $974,909 thousand and $6,297 thousand from AUST and ACMK, respectively, with no expiration and $154 thousand from a domestic subsidiary, UTI. Tax loss carryforwards is utilized in accordance with the relevant jurisdictional tax laws and regulations. Net losses from foreign subsidiaries are approved by tax authorities in respective jurisdiction to offset future taxable profits. Under the ROC tax laws, approved tax losses of AUO and its domestic subsidiaries can be carried forward for 10 years to offset future taxable profits. As of December 31, 2019, the expiration period for abovementioned unrecognized deferred tax assets of unused tax losses carryforwards were as follows: Year of assessment Unrecognized deferred tax assets Expiration in year (in thousands) 2011 $ 2,904,785 2020 ~ 2021 2012 11,042,933 2021 ~ 2022 2013 1,747,050 2022 ~ 2023 2014 2,347,376 2023 ~ 2024 2015 2,159,621 2020 ~ 2025 2016 4,259,267 2020 ~ 2026 2017 2,314,089 2021 ~ 2026 2018 1,279,958 2023 ~ 2028 2019 (estimated) 4,390,051 2023 ~ 2029 $ 32,445,130 As of December 31, 2019, the aggregate taxable temporary differences associated with investments in subsidiaries not recognized as deferred tax liabilities amounted to $277,670 thousand. (g) Assessments by the tax authorities As of December 31, 2019, the tax authorities have completed the examination of income tax returns of AUO through 2017.

Earnings (Loss) per Share

Earnings (Loss) per Share	12 Months Ended
	Dec. 31, 2019
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Earnings (Loss) per Share	38. Earnings (Loss) per Share (a) Basic earnings (loss) per share for the years ended December 31, 2017, 2018 and 2019 were calculated as follows: For the years ended December 31, 2017 2018 2019 (in thousands, except for per share data) Profit (loss) attributable to AUO’s shareholders $ 42,609,500 13,071,646 (18,767,191 ) Weighted-average number of common shares outstanding during the year (basic) 9,624,245 9,624,245 9,597,268 Basic earnings (loss) per share $ 4.43 1.36 (1.96 ) (b) Diluted earnings (loss) per share for the years ended December 31, 2017, 2018 and 2019 were calculated as follows: For the years ended December 31, 2017 2018 2019 (in thousands, except for per share data) Profit (loss) attributable to AUO’s shareholders $ 42,609,500 13,071,646 (18,767,191 ) Weighted-average number of common shares outstanding during the year (including the effect of dilutive potential common stock): Weighted-average number of common shares (basic) 9,624,245 9,624,245 9,597,268 Effect of employee remuneration in stock 347,903 164,609 - Weighted-average number of common shares (diluted) 9,972,148 9,788,854 9,597,268 Diluted earnings (loss) per share $ 4.27 1.34 (1.96 ) Since AUO incurred net loss for the year ended December 31, 2019, there were no potential ordinary shares with dilutive effect for the year.

Cash Flow Information

Cash Flow Information	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Cash Flow Information	39. Cash Flow Information The reconciliation of liabilities to cash flows arising from financing activities was as follows: Long-term borrowings (including current installments) Short-term borrowings Guarantee deposits Total liabilities from financing activities (in thousands) Balance at January 1, 2017 $ 124,262,620 526,723 838,263 125,627,606 Cash flows (12,571,198 ) 2,903,927 (34,654 ) (9,701,925 ) Non-cash changes: Changes in exchange rate (1,142,980 ) (6,274 ) 34,873 (1,114,381 ) Effect of change in consolidated entities (84,187 ) - - (84,187 ) Amortization on transaction costs 143,755 - - 143,755 Balance at December 31, 2017 $ 110,608,010 3,424,376 838,482 114,870,868 Cash flows (24,464,961 ) (2,817,894 ) (13,402 ) (27,296,257 ) Non-cash changes: Changes in exchange rate 27,663 (60,010 ) (8,568 ) (40,915 ) Amortization on transaction costs 134,606 - - 134,606 Balance at December 31, 2018 $ 86,305,318 546,472 816,512 87,668,302 Long-term borrowings (including current installments) Short-term borrowings Guarantee deposits Lease liabilities Total liabilities from financing activities (in thousands) Balance at January 1, 2019 $ 86,305,318 546,472 816,512 12,689,526 100,357,828 Cash flows 26,501,234 1,188,250 (1,828 ) (694,922 ) 26,992,734 Non-cash changes: Increase (decrease) in lease liabilities - - - (872,224 ) (872,224 ) Changes in exchange rate (1,059,445 ) (9,120 ) (29,228 ) (31,303 ) (1,129,096 ) Amortization on transaction costs 221,285 - - - 221,285 Balance at December 31, 2019 $ 111,968,392 1,725,602 785,456 11,091,077 125,570,527

Financial Instruments

Financial Instruments	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Financial Instruments	40. Financial Instruments (1) Fair value and carrying amount The carrying amounts of the Company’s current non-derivative financial instruments, including financial assets at amortized cost and financial liabilities at amortized cost, were considered to approximate their fair value due to their short-term nature. This methodology applies to cash and cash equivalents, receivables or payables (including related parties), other current financial assets, and short-term borrowings. Disclosures of fair value are not required for the financial instruments abovementioned and lease liabilities. Other than those, the carrying amount and fair value of other financial instruments of the Company as of December 31, 2018 and 2019 were as follows: December 31, 2018 December 31, 2019 Carrying Amount Fair Value Carrying Amount Fair Value (in thousands) Financial assets: Financial assets at FVTPL: Financial assets mandatorily measured at FVTPL $ 1,709,531 1,709,531 1,521,406 1,521,406 Financial assets at FVTOCI 6,979,925 6,979,925 7,545,171 7,545,171 Financial assets at amortized cost: Long-term receivables 930,001 930,001 5,812 5,812 Refundable deposits 716,097 716,097 663,911 663,911 Financial liabilities: Financial liabilities at FVTPL: Financial liabilities held for trading 22,115 22,115 18,859 18,859 Financial liabilities at amortized cost: Long-term borrowings (including current installments) 86,305,318 86,305,318 111,968,392 111,968,392 Guarantee deposits 816,512 816,512 785,456 785,456 (2) Valuation techniques and assumptions applied in fair value measurement The fair values of financial assets and financial liabilities with standard terms and conditions and traded in active markets are determined with reference to quoted market prices. The fair values of other financial assets and financial liabilities without quoted market prices are estimated using valuation approach. The estimates and assumptions used are the same as those used by market participants in the pricing of financial instruments. Fair value of foreign currency forward contract is measured based on the maturity date of each contract with quoted spot rate and quoted swap points from Reuters quote system. Fair value of structured investment product is measured based on the discounted future cash flows arising from principal consideration and probable gains estimate to be received. Fair value of long-term receivables is determined by discounting the expected cash flows at a market interest rate. The refundable deposits and guarantee deposits are based on carrying amount as there is no fixed maturity. The fair value of floating-rate long-term borrowings approximates to their carrying value. (3) Fair value measurements recognized in the consolidated statements of financial position The Company determines fair value based on assumptions that market participants would use in pricing an asset or a liability in the principal market. When considering market participant assumptions in fair value measurements, the following fair value hierarchy distinguishes between observable and unobservable inputs, which are categorized in one of the following levels: (i) Level 1 inputs: Unadjusted quoted prices for identical assets or liabilities in active markets. (ii) Level 2 inputs: Other than quoted prices included within Level 1, inputs are observable for the asset or liability, either directly (i.e. as prices) or indirectly (i.e. derived from prices). (iii) Level 3 inputs: Derived from valuation techniques that include inputs for the asset or liability that are not based on observable market data (unobservable inputs). The fair value measurement level of an asset or a liability within their fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. The Company uses valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities measured at fair value on a recurring basis were as follows: Level 1 Level 2 Level 3 Total (in thousands) December 31, 2018 Financial assets at FVTPL: Financial assets mandatorily measured at FVTPL $ - 1,709,531 - 1,709,531 Financial assets at FVTOCI 6,803,900 - 176,025 6,979,925 Financial assets at amortized cost: Long-term receivables - 930,001 - 930,001 Financial liabilities at FVTPL: Financial liabilities held for trading - 22,115 - 22,115 December 31, 2019 Financial assets at FVTPL: Financial assets mandatorily measured at FVTPL $ - 1,521,406 - 1,521,406 Financial assets at FVTOCI 7,356,501 - 188,670 7,545,171 Financial assets at amortized cost: Long-term receivables - 5,812 - 5,812 Financial liabilities at FVTPL: Financial liabilities held for trading - 18,859 - 18,859 There were no transfers between Level 1 and 2 for the years ended December 31, 2018 and 2019. (4) Reconciliation for recurring fair value measurements categorized within Level 3 For the year ended December 31, 2017 (in thousands) Available-for-sale financial assets without quoted market prices Balance at the beginning of the year $ 193,582 Net realized/unrealized losses included in profit or loss (i) (30,000 ) Purchases 14,233 Balance at the end of the year $ 177,815 (i) Change in unrealized losses, which were included in profit or loss, relating to those available-for-sale assets without quoted market prices held at December 31, 2017 was $30,000 thousand. For the years ended December 31, 2018 2019 (in thousands) Financial assets at FVTOCI － Balance at the beginning of the year $ - 176,025 Adjustments on initial application of IFRS 9 177,815 - Net gains (losses) included in other comprehensive income 9,990 (33,501 ) Purchases 34,157 47,182 Disposals (45,937 ) - Effect of exchange rate change - (1,036 ) Balance at the end of the year $ 176,025 188,670 (5) Description of valuation processes and quantitative disclosures for fair value measurements categorized within Level 3 The Company’s management reviews the policy and procedures of fair value measurements at least once at the end of the annual reporting period, or more frequently as deemed necessary. When a fair value measurement involves one or more significant inputs that are unobservable, the Company monitors the valuation process discreetly and examines whether the inputs are used the most relevant market data available. Item Valuation technique Significant Inter-relationship between significant Financial assets at FVTOCI–equity instruments without active market Market approach Ÿ Price-Book ratio (0.99~5.2 at Dec. 31, 2018 and 0.7~2.95 at Dec. 31, 2019) Ÿ Price-Earnings ratio (14.69~112.13 at Dec. 31, 2018 and 7.85~31.28 at Dec. 31, 2019) Ÿ Discount for lack of marketability (20% at Dec. 31, 2018 and 20% ~28% at Dec. 31, 2019) Ÿ The higher the price-book ratio is, the higher the fair value is. Ÿ The higher the price-earnings ratio is, the higher the fair value is. Ÿ The greater degree of lack of marketability is, the lower the fair value is.

Financial Risk Management

Financial Risk Management	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Financial Risk Management	41. Financial Risk Management (a) Risk management framework The managerial officers of related divisions are appointed to review, control, trace and monitor the strategic risks, financial risks and operational risks faced by the Company. The managerial officers report to executive officers the progress of risk controls from time to time and, if necessary, report to the board of directors, depending on the extent of impact of risks. (b) Financial risk information Hereinafter discloses information about the Company’s exposure to variable risks, and the goals, policies and procedures of the Company’s risk measurement and risk management. The Company is exposed to the following risks due to usage of financial instruments: (1) Credit risk Credit risk is the risk of financial loss to the Company if a customer or counterparty to a financial instrument fails to meet its contractual obligations. The Company’s exposures to credit risk are mainly from: (i) The carrying amount of financial assets recognized in the consolidated statements of financial position. (ii) The amount of contingent liabilities as a result from the Company providing financial guarantee to its customers. The Company’s potential credit risk is derived primarily from cash in bank, cash equivalents and trade receivables. The Company deposits its cash and cash equivalent investments with various reputable financial institutions of high credit quality. The Company also entered into reverse repurchase agreements with securities firms or banks in Taiwan covering government bonds that classified as cash equivalents. There should be no major concerns for the performance capability of trading counterparts. Management performs periodic evaluations of the relative credit standing of these financial institutions and limits the amount of credit exposure with any one institution. Management believes that there is a limited concentration of credit risk in cash and cash equivalent investments. The majority of the Company’s customers are in high technology industries. Management continuously evaluates and controls the credit quality, credit limit and financial strength of its customers to ensure any overdue receivables are taken necessary procedures. The Company also flexibly makes use of prepayments, accounts receivable factoring and credit insurance as credit enhancement instruments. If necessary, the Company will request collaterals or assurance from its customers in order to reduce the credit risk from particular customers. Additionally, on the reporting date, the Company reviews the recoverability of its receivables to provide appropriate valuation allowances. Consequently, management believes there is a limited concentration of its credit risk. For the years ended December 31, 2018 and 2019, the Company’s five largest customers accounted for 36.6% and 38.7%, respectively, of the Company’s consolidated net revenue. There is no other significant concentration of credit risk. Refer to note 11 for expected credit loss analysis of accounts receivable and the movement in the loss allowance of accounts receivable. For credit of guarantee, the Company’s policy is to provide financial guarantees only to subsidiaries. (2) Liquidity risk Liquidity risk is the risk that the Company will encounter difficulty in meeting the obligations associated with its financial liabilities that are settled by delivering cash or another financial asset due to an economic downturn or unbalanced demand and supply resulting in a significant drop in product prices. Liquidity risk of the Company is monitored through its corporate treasury department which tracks the development of the actual cash flow position for the Company and uses input from a number of sources in order to forecast the overall liquidity position both on a short and long term basis. Corporate treasury invests surplus cash in money market deposits with appropriate maturities to ensure sufficient liquidity is available to meet liabilities when due, without incurring unacceptable losses or risking damage to the Company’s reputation. The following, except for payables (including related parties) and equipment and construction payable, are the contractual maturities of other financial liabilities. The amounts include estimated interest payments (except for short-term borrowings) but exclude the impact of netting agreements. Contractual cash 2019.1.1~ 2020.1.1~ 2022.1.1~ 2024 and (in thousands) December 31, 2018 Non-derivative financial liabilities Short-term borrowings $ 546,472 546,472 - - - Long-term borrowings (including current installments) 92,485,536 31,854,500 45,935,987 14,395,139 299,910 Guarantee deposits 816,512 36,977 - - 779,535 Derivative financial instruments Foreign currency forward contracts － inflows (12,453,853 ) (12,453,853 ) - - - Foreign currency forward contracts － 12,436,885 12,436,885 - - - $ 93,831,552 32,420,981 45,935,987 14,395,139 1,079,445 Contractual cash 2020.1.1~ 2021.1.1~ 2023.1.1~ 2025 and (in thousands) December 31, 2019 Non-derivative financial liabilities Short-term borrowings $ 1,725,602 1,725,602 - - - Long-term borrowings (including current installments) 119,185,207 12,149,855 55,120,591 50,630,751 1,284,010 Guarantee deposits 785,456 23,510 11,187 - 750,759 Derivative financial instruments Foreign currency forward contracts － inflows (8,731,109 ) (8,731,109 ) - - - Foreign currency forward contracts － 8,727,770 8,727,770 - - - $ 121,692,926 13,895,628 55,131,778 50,630,751 2,034,769 The Company is not expecting that the cash flows included in the maturity analysis could occur significantly earlier or at significantly different amounts. As at December 31, 2019, the Company’s total current assets exceeded its total current liabilities by $52,664,413 thousand. Management believes the Company’s existing unused credit facilities under its existing loan agreements, together with net cash flows expected to be generated from its operating activities, will be sufficient for the Company to fulfill its payment obligations over the next twelve months. Therefore, management believes that the Company does not have significant liquidity risk. (3) Market risk Market risk is the risk that changes in market prices, such as foreign exchange rates, interest rates and equity prices, which will affect the Company’s income or the value of its holdings of financial instruments. The objective of market risk management is to manage and control market risk exposures within acceptable range, while optimizing the return. The Company buys and sells derivatives, and also incurs financial assets and liabilities, in order to manage market risks. All such transactions are executed in accordance with the Company’s handling procedures for conducting derivative transactions, and also monitored by internal audit department. (i) Currency risk The Company is exposed to currency risk on foreign currency denominated financial assets and liabilities arising from operating, financing and investing activities such that the Company uses forward exchange contracts to hedge its currency risk. Gains and losses derived from the foreign currency fluctuations on underlying assets and liabilities are likely to offset. However, transactions of derivative financial instruments help minimize the impact of foreign currency fluctuations, but the risk cannot be fully eliminated. The Company periodically examines portions exposed to currency risks for individual asset and liability denominated in foreign currency and uses forward contracts as hedging instruments to hedge positions exposed to risks. The contracts have maturity dates that do not exceed one year, and do not meet the criteria for hedge accounting. A. Exposure of currency risk The Company’s significant exposure to foreign currency risk was as follows: Foreign currency amounts Exchange NTD (in thousands) (in thousands) December 31, 2018 Financial assets Monetary items USD $ 2,092,501 30.8020 64,453,216 JPY 11,872,572 0.2775 3,294,639 EUR 29,681 35.2036 1,044,878 Foreign currency amounts Exchange NTD (in thousands) (in thousands) Non-monetary items USD $ 2,799 30.8020 86,215 RMB 20,258 4.4813 90,782 Financial liabilities Monetary items USD 1,188,175 30.8020 36,598,166 JPY 25,296,499 0.2775 7,019,778 EUR 209 35.2036 7,358 December 31, 2019 Financial assets Monetary items USD $ 1,499,405 30.1350 45,184,570 JPY 22,122,120 0.2768 6,123,403 EUR 46,595 33.7422 1,572,218 Non-monetary items USD 1,726 30.1350 52,013 RMB - 4.3155 - Financial liabilities Monetary items USD 1,515,582 30.1350 45,672,064 JPY 22,187,729 0.2768 6,141,563 EUR 239 33.7422 8,064 B. Sensitivity analysis The Company’s exposure to foreign currency risk arises mainly from the translation of the foreign currency exchange gains and losses on cash and cash equivalents, trade receivables, loans and borrowings and trade payables that are denominated in foreign currency. Depreciation or appreciation of the NTD by 1% against the USD, EUR and JPY at December 31, 2018 and 2019, while all other variables were remained constant, would have increased or decreased the net profit before tax for the years ended December 31, 2018 and 2019 as follows: For the years ended December 31, 2018 2019 (in thousands) 1% of depreciation $ 251,674 10,585 1% of appreciation (251,674 ) (10,585 ) C. Foreign exchange gain (loss) on monetary items With varieties of functional currencies within the consolidated entities of the Company, the Company disclosed foreign exchange gain (loss) on monetary items in aggregate. The aggregate of realized and unrealized foreign exchange losses for the years ended December 31, 2017, 2018 and 2019 were $1,364,929 thousand, $41,391 thousand and $168,499 thousand, respectively. (ii) Interest rate risk The Company’s exposure to changes in interest rates is mainly from floating-rate long-term debt obligations. Any change in interest rates will cause the effective interest rates of long-term borrowings to change and thus cause the future cash flows to fluctuate over time. The Company will, depending on the market condition, enter into and designate interest rate swaps as hedges of the variability in cash flows attributable to interest rate risk. Assuming the amount of floating-rate debts at the end of the reporting period had been outstanding for the entire year and all other variables were remained constant, an increase or a decrease in the interest rate by 0.25% would have resulted in a decrease or an increase in the net profit before tax for the years ended December 31, 2017, 2018 and 2019 by $277,612 thousand, $216,955 thousand and $280,558 thousand, respectively. (iii) Equity price risk See note 9 and note 10 for disclosure of equity price risk analysis.

Capital Management

Capital Management	12 Months Ended
	Dec. 31, 2019
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Capital Management	42. Capital Management Through clear understanding and managing of significant changes in external environment, related industry characteristics, and corporate growth plan, the Company manages its capital structure to ensure it has sufficient financial resources to sustain proper liquidity, to invest in capital expenditures and research and development expenses, to repay debts and to distribute dividends in accordance to its plan. The management pursues the most suitable capital structure by monitoring and maintaining proper financial ratios as below. The Company aims to enhance the returns of its shareholders through achieving an optimized debt-to-equity ratio from time to time. December 31, 2018 2019 (in thousands) Short-term borrowings $ 546,472 1,725,602 Long-term borrowings (including current installments) 86,305,318 111,968,392 Total liabilities 190,765,874 207,455,122 Total equity 207,785,306 178,901,874 Debt-to-equity ratio 92 % 116 % Net debt-to-equity ratio (1) 9 % 19 % (1) Net debt-to-equity ratio is defined as short-term borrowings plus long-term borrowings less cash and cash equivalents and divided by total equity.

Related-party Transactions

Related-party Transactions	12 Months Ended
	Dec. 31, 2019
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Related-party Transactions	43. Related-party Transactions All inter-company transactions and balances between AUO and its subsidiaries are eliminated in the consolidated financial statements. The transactions between the Company and other related parties are set out as follows: (a) Compensation to key management personnel Key management personnel’s compensation comprised: For the years ended December 31, 2017 2018 2019 (in thousands) Short-term employee benefits $ 566,231 345,019 243,203 Post-employment benefits 2,244 2,547 2,633 $ 568,475 347,566 245,836 (b) Except for otherwise disclosed in other notes to the consolidated financial statements, the Company’s significant related party transactions and balances were as follows: (1) Sales Sales Accounts receivable For the years ended December 31, December 31, 2017 2018 2019 2018 2019 (in thousands) Associates $ 1,216,868 1,898,336 1,227,987 696,423 280,009 Others (i) 11,959,720 12,050,450 10,347,963 2,057,830 1,498,490 $ 13,176,588 13,948,786 11,575,950 2,754,253 1,778,499 The collection terms for sales to related parties were 25 to 55 days from the end of the month during which the invoice is issued. The pricing for sales to related parties were not materially different from those with third parties. (2) Purchases Purchases Accounts payable to related parties For the years ended December 31, December 31, 2017 2018 2019 2018 2019 (in thousands) Associates $ 8,667,555 9,185,563 8,664,439 3,664,742 2,825,292 Joint ventures 1,057,106 1,449,636 1,027,147 - 72,942 Others (i) 17,549,228 18,589,791 17,077,497 4,496,444 4,052,594 $ 27,273,889 29,224,990 26,769,083 8,161,186 6,950,828 The payment terms for purchases from related parties were 30 to 120 days. The pricing and payment terms with related parties were not materially different from those with third parties. (3) Acquisition of property, plant and equipment For the years ended December 31, 2017 2018 2019 (in thousands) Associates $ 1,549 6,527 6,555 Others (i) 2,801 4,449 17,436 $ 4,350 10,976 23,991 (4) Disposal of property, plant and equipment and others Proceeds from disposal For the years ended December 31, 2017 2018 2019 (in thousands) Others (i) $ 3,352 - 835 Gains on disposal For the years ended December 31, 2017 2018 2019 (in thousands) Others (i) $ 2,212 - 72 (5) Other related party transactions Other receivables due from December 31, 2018 2019 (in thousands) Associates $ 8,161 2,727 Others (i) 4,784 1,229 $ 12,945 3,956 Other payables due to related parties (including payable for equipment) December 31, 2018 2019 (in thousands) Associates $ 18,148 13,980 Others (i) 10,027 35,991 $ 28,175 49,971 Rental income For the years ended December 31, 2017 2018 2019 (in thousands) Associates $ 48,223 55,044 52,227 Joint ventures 6,611 6,611 6,611 Others (i) 82,427 91,222 107,587 $ 137,261 152,877 166,425 Administration and other income For the years ended December 31, 2017 2018 2019 (in thousands) Associates $ 14,311 18,580 17,980 Joint ventures - 1,060 223 Others (i) 9,246 8,789 7,996 $ 23,557 28,429 26,199 Other expenses For the years ended December 31, 2017 2018 2019 (in thousands) Associates $ 28,017 37,155 20,157 Joint ventures 1,389 567 36 Others (i) 35,040 29,336 59,287 $ 64,446 67,058 79,480 (i) Entities which are substantive related parties of the Company but not been accounted for using the equity method, mainly Qisda Corporation and its subsidiaries. The Company leased portion of its facilities to related parties. The collection term was 15 days from quarter-end, and the pricing was not materially different from that with third parties. For the years ended December 31, 2017, 2018 and 2019, the Company had received cash dividends from related parties of $420,547 thousand, $668,228 thousand and $566,865 thousand, respectively.

Pledged Assets

Pledged Assets	12 Months Ended
	Dec. 31, 2019
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Pledged Assets	44. Pledged Assets The carrying amounts of the assets which the Company pledged as collateral were as follows: December 31, Pledged assets Pledged to secure 2018 2019 (in thousands) Restricted cash in banks (i) Customs duties and guarantee for warranties $ 91,753 35,809 Land and building Long-term borrowings 27,696,480 28,423,642 Machinery and equipment Long-term borrowings 37,317,602 42,968,184 $ 65,105,835 71,427,635 (i) Classified as other current financial assets and other noncurrent assets by its liquidity.

Contingent Liabilities and Comm

Contingent Liabilities and Commitments	12 Months Ended
	Dec. 31, 2019
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Contingent Liabilities and Commitments	45. Contingent Liabilities and Commitments The significant commitments and contingencies of the Company as of December 31, 2019, in addition to those disclosed in other notes to the consolidated financial statements, were as follows: (a) Outstanding letters of credit As at December 31, 2019, the Company had the following outstanding letters of credit for the purpose of purchasing machinery and equipment and materials: Currency December 31, (in thousands) USD 5,768 JPY 1,951,409 (b) Technology licensing agreements Starting in 1998, AUO has entered into technical collaboration, patent licensing, and/or patent cross licensing agreements with Fujitsu Display Technologies Corp. (subsequently assumed by Fujitsu Limited), Toppan Printing Co., Ltd. (“Toppan Printing”), Semiconductor Energy Laboratory Co., Ltd., Japan Display Inc. (formerly Japan Display East Inc./Hitachi Displays, Ltd.), Panasonic Liquid Crystal Display Co., Ltd. (formerly IPS Alpha Technology, Ltd.), LG Display Co., Ltd., Sharp Corporation, Samsung Electronics Co., Ltd., Hydis Technologies Co., Ltd., Sanyo Electric Co., Ltd., Seiko Epson Corporation and others. AUO believes that it is in compliance with the terms and conditions of the aforementioned agreements. (c) Purchase commitments Starting from 2006, DPTW has entered into a long-term materials supply agreement with Evonik Forhouse Optical Polymers Corp. (“EFOP”), a joint venture of the Company. Under the agreement, DPTW and EFOP agreed on the supply of certain optical-grade molding compounds at agreed prices and quantities. As at December 31, 2019, significant outstanding purchase commitments for construction in progress, property, plant and equipment totaled $7,639,758 thousand. (d) Litigation (1) Antitrust civil actions lawsuits in the United States and other jurisdictions A lawsuit was filed by certain consumers in Israel against certain LCD manufacturers including AUO in the District Court of the Central District in Israel (“Israeli Court”). The defendants contested various issues including whether the lawsuit was properly served. In December 2016, the Israeli Court overturned the original decision and revoked the permission for this case to serve out of Israeli jurisdiction. The plaintiffs lodged an appeal to the Israeli Supreme Court but the Israeli Supreme Court overruled the appeal in August 2017. In January 2018, the parties reached a settlement agreement and agreed to commence the required proceedings for withdrawing the lawsuit. In April 2019, the Central District Court of Israel in Lod approved the settlement. AUO has complied with all the court ordered directives to finalize the settlement, so the settlement is now completed. In May 2014, LG Electronics Nanjing Display Co., Ltd. and seven of its affiliates filed a lawsuit in Seoul Central District Court against certain LCD manufacturers including AUO, alleging overcharge and claiming damages. AUO does not believe service has been properly made, but in order to protect its rights, AUO has retained counsel to handle the related matter, and at this stage, the final outcome of these matters is uncertain. AUO has been reviewing the merits of this lawsuit on an on-going basis. In September 2018, AUUS received a complaint filed by the Government of Puerto Rico on its own behalf and on behalf of all consumers and governmental agencies of Puerto Rico against certain LCD manufacturers including AUO and AUUS in the Superior Court of San Juan, Court of First Instance alleging unjust enrichment and claiming unspecified monetary damages. AUO has retained counsel to handle the related matter and intends to defend this lawsuit vigorously, and at this stage, the final outcome of these matters is uncertain. AUO is reviewing the merits of this lawsuit on an on-going basis. (2) Alleged patent infringements In July 2018, Vista Peak Ventures, LLC (“VPV”) filed three lawsuits in the United States District Court for the Eastern District of Texas against AUO, claiming infringement of certain of VPV’s patents in the United States relating to the manufacturing of TFT-LCD panels. In the complaints, VPV seeks, among other things, unspecified monetary damages for past damages and an injunction against future infringement. On September 27, 2019, the relevant parties reached a settlement agreement, and all pending lawsuits that have been filed by VPV against AUO were dismissed on October 10, 2019. In addition to the matters described above, the Company is also a party to other litigations or proceedings that arise during the ordinary course of business. Except as mentioned above, the Company, to its knowledge, is not involved as a defendant in any material litigation or proceeding which could be expected to have a material adverse effect on the Company’s business or results of operations. The Company has made certain provisions with respect to certain of the above lawsuits as the management deems appropriate, considering factors such as the nature of the litigation or claims, the materiality of the amount of possible loss, the progress of the cases and the opinions or views of legal counsel and other advisors. However, for certain cases described above where the legal proceedings and/or lawsuits are in their early stage or where management does not have sufficient information for assessment of the financial exposure, management is unable to determine if the final outcome of the cases will be unfavorable to the Company and/or to estimate the potential losses. The ultimate resolution of the legal proceedings and/or lawsuits cannot be predicted with certainty. While management intends to defend certain of the lawsuits described above vigorously, there is a possibility that one or more legal proceedings or lawsuits may result in an unfavorable outcome to the Company. Management will reassess all litigation and claims at each reporting date based on the facts and circumstances that exist at that time, and will make additional provisions or adjustments to previous provisions, as considered necessary under IFRS. Such additional provisions or adjustments may have a material adverse effect on the Company’s business, results of operations and future prospects. See note 25 for further information about legal provisions and the movements in those legal provisions. (e) Others There have been environmental proceedings relating to the development project of the Central Taiwan Science Park in Houli, Taichung, which AUO’s second 8.5-generation fab is located at and which has been established since 2010. The proceedings were initiated by six residents in Houli District, Taichung City (the “Plaintiffs”) to object the administrative dispositions of the environmental assessment and development approval issued in 2010 by the Environmental Protection Administration (“EPA”) of the Executive Yuan of Taiwan to the third phrase development area in the Central Taiwan Science Park (the “Project”). On August 8, 2014, the Plaintiffs reached a settlement with the defendants (i.e. the governmental authorities, including the EPA of the Executive Yuan of Taiwan, the Ministry of Science and Technology (former National Science Council of the ROC Executive Yuan) and the Central Taiwan Science Park Development Office) in the Taipei High Administrative Court. The second phase environmental impact assessment for the Project continues to proceed. On December 14, 2017, the EPA of the Executive Yuan of Taiwan held the third review meeting of the investigation group. The review meeting reached the conclusion of suggesting approval for the Project. On November 6, 2018, the EPA approved the Project, but on December 6, 2018, five residents in Houli District, Taichung City filed administrative appeal to the Appeals Review Committee of the Executive Yuan requesting a withdrawal of the approval. The appeal was rejected by the Appeal Review Committee on October 24, 2019 and the residents have proceeded to file an administrative action for invalidating the environmental assessment again, this time against the EPA. Currently management does not believe that this event will have a material adverse effect on the Company’s operation and will continue to monitor the development of this event.

Segment, Geographic and Revenue

Segment, Geographic and Revenue Information	12 Months Ended
	Dec. 31, 2019
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Segment, Geographic and Revenue Information	46. Segment, Geographic and Revenue Information (a) Operating segment information The Company has two operating segments: display and energy. The display segment generally is engaged in the research, development, design, manufacturing and sale of flat panel displays and most of our products are TFT-LCD panels. The energy segment primarily is engaged in the design, manufacturing and sale of ingots, solar wafers and solar modules, as well as providing technical engineering services and maintenance services for solar system projects. The Company’s operating segment information for the years ended December 31, 2017, 2018 and 2019 was as follows: For the year ended December 31, 2017 Display segment Energy segment Total (in thousands) Net revenue from external customers $ 322,335,330 18,692,937 341,028,267 Depreciation and amortization $ 34,816,463 1,613,373 36,429,836 Inventory write-down $ 3,423,097 333,629 3,756,726 Segment profit (loss) (i) $ 39,971,375 (832,251 ) 39,139,124 Other income 3,829,897 Other gains and losses (976,560 ) Finance costs (2,867,861 ) Share of profit of equity-accounted investees 239,006 Consolidated profit before income tax $ 39,363,606 For the year ended December 31, 2018 Display segment Energy segment Total (in thousands) Net revenue from external customers $ 290,784,754 16,849,635 307,634,389 Depreciation and amortization $ 32,981,240 1,246,290 34,227,530 Inventory write-down $ 5,094,195 77,557 5,171,752 Segment profit (loss) (i) $ 7,792,505 (1,124,640 ) 6,667,865 Other income 5,412,125 Other gains and losses 1,488,052 Finance costs (2,663,605 ) Share of profit of equity-accounted investees 311,714 Consolidated profit before income tax $ 11,216,151 For the year ended December 31, 2019 Display segment Energy segment Total (in thousands) Net revenue from external customers $ 256,667,222 12,124,472 268,791,694 Depreciation and amortization $ 35,237,582 1,020,137 36,257,719 Inventory write-down $ 5,109,473 76,031 5,185,504 Segment profit (loss) (i) $ (19,484,401 ) (983,547 ) (20,467,948 ) Other income 5,320,271 Other gains and losses (1,595,614 ) Finance costs (3,251,370 ) Share of profit of equity-accounted investees 149,907 Consolidated loss before income tax $ (19,844,754 ) (i) There were no intersegment revenues or other transactions between operating segments for the years ended December 31, 2017, 2018 and 2019. (b) Geographic information The geographic breakdown for the years ended December 31, 2017, 2018 and 2019 was as follows: (1) Net revenue from external customers For the years ended December 31, 2017 2018 2019 Region (in thousands) PRC $ 125,341,648 113,632,037 98,362,235 Taiwan 108,288,387 99,357,882 83,229,594 Singapore 35,939,290 39,370,930 38,534,291 Japan 32,739,262 21,166,864 20,924,003 Others 38,719,680 34,106,676 27,741,571 $ 341,028,267 307,634,389 268,791,694 (2) Consolidated noncurrent assets (ii) December 31, 2018 2019 Region (in thousands) Taiwan $ 161,358,754 163,237,676 PRC 61,284,667 54,890,846 Others 6,941,674 6,301,996 $ 229,585,095 224,430,518 (ii) Noncurrent assets are not inclusive of financial instruments, deferred tax assets, and prepaid pension. (c) Major customer information For the years ended December 31, 2017, 2018 and 2019, sales to individual customers representing greater than 10% of consolidated net revenue were as follows: For the years ended December 31, 2017 % 2018 % 2019 % (in thousands) Customer A $ 43,645,518 13 35,358,013 11 33,142,985 12 (d) Product information The consolidated net revenue by principal products was as follows: For the years ended December 31, 2017 2018 2019 (in thousands) Products for Televisions $ 152,442,198 113,194,567 87,269,763 Products for Mobile PCs and Devices 71,068,304 74,375,305 69,305,510 Products for Monitors 45,696,144 47,024,353 39,522,268 Products for Commercial and Others (iii) 53,128,684 56,190,529 60,569,681 Solar Products 18,692,937 16,849,635 12,124,472 Total $ 341,028,267 307,634,389 268,791,694 (iii) Others include sales from products for other applications and sales of raw materials, components and from service charges.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2019
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Subsequent Events	47. Subsequent Events On February 5, 2020, AUO's Board of Directors resolved to acquire common shares of ADLINK Technology Inc. through tender offer. The tender offer consideration for each common share is NT$57 in cash. On March 12, 2020, we successfully completed the tender offer to acquire a total of 42,310 thousand common shares from ADLINK Technology Inc., which approximately accounts for 19.45% equity interest in ADLINK Technology Inc.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2019
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Statement of IFRS Compliance	(a) Statement of compliance The consolidated financial statements have been prepared in accordance with IFRSs as issued by the IASB.
Disclosure of Basis of Preparation of Financial Statements	(b) Basis of preparation (1) Basis of measurement The consolidated financial statements have been prepared on the historical cost basis except for the following material items in the consolidated statements of financial position: (i) Financial instruments at fair value through profit or loss (including derivative financial instruments) (note 8); (ii) Financial assets at fair value through other comprehensive income (note 9); (iii) Available-for-sale financial assets measured at fair value (note 10); and (iv) Defined benefit asset (liability) is recognized as the fair value of the plan assets less the present value of the defined benefit obligation (note 27). (2) Functional and presentation currency The functional currency of each individual consolidated entity is determined based on the primary economic environment in which the entity operates. The Company’s consolidated financial statements are presented in New Taiwan Dollar (“NTD”), which is also AUO’s functional currency. All financial information presented in NTD has been rounded to the nearest thousand, unless otherwise noted.
Disclosure of Basis of Consolidation	(c) Basis of consolidation (1) Principle of preparation of the consolidated financial statements The Company includes in its consolidated financial statements the results of operations of all controlled entities in which the Compa ny is exposed to, or has rights to, variable returns from its involvement with the entity and has the ability to affect those returns through its power over the entity The financial statements of subsidiaries are included in the consolidated financial statements from the date that control commences until the date that control ceases. Total comprehensive income (loss) in a subsidiary is allocated to the shareholders of AUO and the non-controlling interests even if this results in the non-controlling interests having a deficit balance. Subsidiaries’ financial statements are adjusted to align the accounting policies with those of the Company. Changes in the Company’s ownership interests in a subsidiary that do not result in a loss of control are accounted for as equity transactions. The carrying amounts of the Company’s investment and non-controlling interests are adjusted to reflect the changes in their relative interests in the subsidiary. Any difference between such adjustment and the fair value of the consideration paid or received is recognized directly in equity and attributed to shareholders of AUO. Upon the loss of control, the Company derecognizes the carrying amounts of the assets and liabilities of the subsidiary and non-controlling interests. Any interest retained in the former subsidiary is remeasured at fair value when control is lost. Any surplus or deficit arising from the loss of control is recognized in profit or loss. The gain or loss is measured as the difference between: (i) The aggregate of: a. the fair value of the consideration received, and b. the fair value of any retained investment in the former subsidiary at the date when the Company loses control. (ii) The aggregate of the carrying amount of the former subsidiary’s assets (including goodwill), liabilities and non-controlling interests at the date when the Company loses control. When the Company loses control of a subsidiary, the Company accounts for all amounts previously recognized in other comprehensive income in relation to that subsidiary on the same basis as would be required if the Company had directly disposed of the related assets or liabilities. (2) List of subsidiaries in the consolidated financial statements The consolidated entities were as follows: Name of Investor Name of Subsidiary Main Activities and Location Percentage of Ownership (%) December 31, 2018 December 31, 2019 AUO AU Optronics (L) Corp. (AULB) Holding and trading company (Malaysia) 100.00 100.00 AUO Konly Venture Corp. (Konly) Venture capital investment (Taiwan ROC) 100.00 100.00 AUO Ronly Venture Corp. (Ronly) Venture capital investment (Taiwan ROC) 100.00 100.00 AUO Space Money Inc. (SMI) Sales and leasing of content management system and hardware (Taiwan ROC) 100.00 100.00 AUO U-Fresh Technology Inc. (UTI) Planning, design and development of construction for environmental protection and related project management (Taiwan ROC) 100.00 100.00 AUO ComQi Ltd. (CQIL) Holding company (Israel) 100.00 (1) 100.00 AUO AU Optronics Europe B.V. (AUNL) Sales and sales support of TFT-LCD panels (Netherlands) 100.00 (2) 100.00 AUO, Konly and Ronly Darwin Precisions Corporation (DPTW) Manufacturing, design and sales of TFT-LCD modules, TV set, backlight modules and related parts (Taiwan ROC) 41.05 (3) 41.05 (3) AUO and Konly AUO Crystal Corp. (ACTW) Manufacturing and sales of ingots and solar wafers (Taiwan ROC) 96.02 (4) 100.00 (4) ACTW Sanda Materials Corporation (SDMC) Holding company (Taiwan ROC) 100.00 (5) 100.00 ACTW AUO Crystal (Malaysia) Sdn. Bhd. (ACMK) Manufacturing and sales of solar wafers (Malaysia) 100.00 100.00 SDMC M.Setek Co., Ltd. (M.Setek) Manufacturing and sales of ingots (Japan) 99.9991 99.9991 AULB AU Optronics Corporation America (AUUS) Sales and sales support of TFT-LCD panels (United States) 100.00 100.00 AULB AU Optronics Corporation Japan (AUJP) Sales support of TFT-LCD panels (Japan) 100.00 100.00 Name of Investor Name of Subsidiary Main Activities and Location Percentage of Ownership (%) December 31, 2018 December 31, 2019 AULB AU Optronics Korea Ltd. (AUKR) Sales support of TFT-LCD panels (South Korea) 100.00 100.00 AULB AU Optronics Singapore Pte. Ltd. (AUSG) Holding company and sales support of TFT-LCD panels (Singapore) 100.00 100.00 AULB AU Optronics (Czech) s.r.o. (AUCZ) (6) Assembly of solar modules (Czech Republic) 100.00 100.00 AULB AU Optronics (Shanghai) Co., Ltd. (AUSH) Sales support of TFT-LCD panels (PRC) 100.00 100.00 AULB AU Optronics (Xiamen) Corp. (AUXM) Manufacturing, assembly and sales of TFT-LCD modules (PRC) 100.00 100.00 AULB AU Optronics (Suzhou) Corp., Ltd. (AUSZ) Manufacturing, assembly and sales of TFT-LCD modules (PRC) 100.00 100.00 AULB AU Optronics Manufacturing (Shanghai) Corp. (AUSJ) Manufacturing and assembly of TFT-LCD modules; leasing (PRC) 100.00 100.00 AULB AU Optronics (Slovakia) s.r.o. (AUSK) Repairing of TFT-LCD modules (Slovakia Republic) 100.00 100.00 AULB AFPD Pte., Ltd. (AUST) Manufacturing TFT-LCD panels based on low temperature polysilicon technology (Singapore) 100.00 100.00 AULB AU Optronics (Kunshan) Co., Ltd. (AUKS) Manufacturing and sales of 51.00 51.00 AULB a.u. Vista Inc. (AUVI) Research and development and IP related business (United States) 100.00 100.00 AULB and DPTW BriView (L) Corp. (BVLB) Holding company (Malaysia) 100.00 100.00 AUSG AUO Energy (Tianjin) Corp. (AETJ) (6) Manufacturing and sales of solar modules (PRC) 100.00 - AUSG AUO Green Energy America Corp. (AEUS) Sales support of solar-related products (United States) 100.00 100.00 AUSG AUO Green Energy Europe B.V. (AENL) Sales support of solar-related products (Netherlands) 100.00 100.00 AUXM BriView (Xiamen) Corp. (BVXM) Manufacturing and sales of liquid crystal products and related parts (PRC) 100.00 100.00 AUSH AUO Care Information Tech. (Suzhou) Co., Ltd. (A-Care) Design, development and sales of software and hardware for health care industry (PRC) 100.00 100.00 Name of Investor Name of Subsidiary Main Activities and Location Percentage of Ownership (%) December 31, 2018 December 31, 2019 AUSH U-Fresh Technology (Suzhou) Co., Ltd. (UFSZ) Planning, design and development of construction project for environmental protection and related project management (PRC) 100.00 (7) 100.00 AUSH Edgetech Data Technologies (Suzhou) Corp., Ltd. (EDT) Design and sales of software and hardware integration system and equipment relating to intelligent manufacturing (PRC) 100.00 (7) 100.00 AUSH Mega Insight Smart Manufacturing (Suzhou) Corp., Ltd. (MIS) Development and licensing of software relating to intelligent manufacturing, and related consulting services (PRC) 100.00 (7) 100.00 UFSZ U-Fresh Environmental Technology (Shandong) Co., Ltd. (UFSD) Planning, design and development of construction project for environmental protection and related project management (PRC) - 100.00 (7) CQIL ComQi Holdings Ltd. (CQHLD) Holding company (United Kingdom) 100.00 (1) 100.00 CQHLD ComQi UK Ltd. (CQUK) Sales support of content management system (United Kingdom) 100.00 (1) 100.00 CQHLD ComQi Inc. (CQUS) Sales of content management system and hardware (United States) 100.00 (1) 100.00 CQHLD ComQi Canada Inc. (CQCA) Research and development of content management system (Canada) 100.00 (1) 100.00 CQUS JohnRyan Limited (JRUK) Development and sales of content management system and sales of related hardware (United Kingdom) - 100.00 (7) CQUS JohnRyan Inc. (JRUS) Development and sales of content management system and sales of related hardware (United States) - 100.00 (7) DPTW Darwin Precisions (L) Corp. (DPLB) Holding company (Malaysia) 100.00 100.00 DPTW Forhouse International Holding Ltd. (FHVI) Holding company (BVI) 100.00 100.00 DPTW Force International Holding Ltd. (FRVI) (6) Holding company (BVI) 100.00 - DPTW and FRVI Forefront Corporation (FFMI) Holding company (Mauritius) 100.00 100.00 (6) Name of Investor Name of Subsidiary Main Activities and Location Percentage of Ownership (%) December 31, 2018 December 31, 2019 FHVI Fortech International Corp. (FTMI) Holding company (Mauritius) 100.00 100.00 FHVI Forward Optronics International Corp. (FWSA) Holding company (Samoa) 100.00 100.00 FHVI Prime Forward International Ltd. (PMSA) Holding company (Samoa) 100.00 100.00 FFMI Forhouse Electronics (Suzhou) Co., Ltd. (FHWJ) Manufacturing of motorized treadmills (PRC) 100.00 100.00 FTMI Fortech Electronics (Suzhou) Co., Ltd. (FTWJ) Manufacturing and sales of backlight modules and related parts (PRC) 100.00 100.00 FWSA and FTMI Suzhou Forplax Optronics Co., Ltd. (FPWJ) Manufacturing and sales of precision plastic parts (PRC) 100.00 100.00 PMSA Fortech Electronics (Kunshan) Co., Ltd. (FTKS) Manufacturing and sales of backlight modules and related parts (PRC) 100.00 100.00 DPLB Darwin Precisions (Hong Kong) Limited (DPHK) Holding company (Hong Kong) 100.00 100.00 DPLB Darwin Precisions (Slovakia) s.r.o. (DPSK) Manufacturing and sales of automotive parts (Slovakia Republic) 100.00 100.00 DPHK Darwin Precisions (Suzhou) Corp. (DPSZ) Manufacturing and sales of backlight modules and related parts (PRC) 100.00 100.00 DPHK Darwin Precisions (Xiamen) Corp. (DPXM) Manufacturing and sales of backlight modules and related parts (PRC) 100.00 100.00 BVLB BriView (Hefei) Co., Ltd. (BVHF) Manufacturing and sales of liquid crystal products and related parts (PRC) 100.00 100.00 Note 1: In March 2018, the Company acquired 100% of the shareholdings of CQIL and its subsidiaries (hereinafter referred to as “ComQi”) and therefore, obtained control over ComQi. Refer to note 15 for further details. Note 2: As part of a business restructuring, AULB disposed all of its shareholdings in AUNL to AUO in December 2018. This was treated as an equity transaction as there was no change in control of AUNL by the Company. Note 3: Although the Company did not own more than 50% of the DPTW’s ownership interests, it was considered to have de facto control over the main operating policies of DPTW. As a result, DPTW was accounted for as a subsidiary of the Company. Note 4: As part of a business restructuring, Konly and Ronly successively disposed its shareholdings in ACTW to AUO in December 2018 and February 2019. This was treated as an equity transaction as there was no change in control of ACTW by the Company. Note 5: As part of a business restructuring, AUO, Konly and Ronly disposed all of their shareholdings in SDMC to ACTW during the second quarter of 2018. This was treated as an equity transaction as there was no change in control of SDMC by the Company. Note 6: As of December 31, 2019, AETJ and FRVI were liquidated and AUCZ is still in the process of liquidation. After the liquidation of FRVI, its ownership of FFMI was transferred to DPTW. Note 7: UFSZ was incorporated in February 2018. EDT and MIS were incorporated in August 2018. UFSD was incorporated in May 2019. JRUK and JRUS were incorporated in October 2019.
Description of Accounting Policy for Foreign Currency Translation	(d) Foreign currency (1) Foreign currency transactions Transactions in foreign currencies are translated to the respective functional currencies of the individual entities of the Company at exchange rates at the dates of the transactions. Monetary assets and liabilities denominated in foreign currencies at the reporting date are retranslated to the functional currency at the exchange rate at that date and the resulting exchange differences are included in profit or loss for the year. Non-monetary assets and liabilities denominated in foreign currencies that are measured at fair value are retranslated to the functional currency at the exchange rate at the date when the fair value was determined. The resulting e xchange differences are included in profit or loss for the year except for those arising from the retranslation of non-monetary items in respect of which gains and losses are recognized directly in other comprehensive income, in which case, the exchange differences are also recognized directly in other comprehensive income Exchange differences arising from the effective portion of changes in the fair value of derivatives that are designated and qualified as cash flow hedges are recognized in other comprehensive income. (2) Foreign operations For the purpose of presenting consolidated financial statements, the assets and liabilities of the Company’s foreign operations are translated into NTD using the exchange rates at each reporting date. Income and expenses of foreign operations are translated at the average exchange rates for the period unless the exchange rates fluctuate significantly during the period; in that case, the exchange rates at the dates of the transactions are used. Foreign currency differences are recognized in other comprehensive income and accumulated in equity (attributed to shareholders of AUO and non-controlling interests as appropriate).
Description of Accounting Policy for Classification of Current and Non Current Assets and Liabilities	(e) Classification of current and non-current assets and liabilities An asset is classified as current when: (1) The asset expected to realize, or intends to sell or consume, in its normal operating cycle; (2) The asset primarily held for the purpose of trading; (3) The asset expected to realize within twelve months after the reporting date; or (4) Cash and cash equivalent excluding the asset restricted to be exchanged or used to settle a liability for at least twelve months after the reporting date. All other assets are classified as non-current. A liability is classified as current when: (1) The liability expected to settle in its normal operating cycle; (2) The liability primarily held for the purpose of trading; (3) The liability is due to be settled within twelve months after the reporting date; or (4) The Company does not have an unconditional right to defer settlement of the liability for at least twelve months after the reporting 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. All other liabilities are classified as non-current.
Description of Accounting Policy for Determining Components of Cash and Cash Equivalents	(f) Cash and cash equivalents Cash comprises cash balances and demand deposits. Cash equivalents comprise short-term highly liquid investments that are readily convertible into known amount of cash and are subject to an insignificant risk of changes in their fair value. Time deposits with short-term maturity but not for investments and other purposes and are qualified with the aforementioned criteria are classified as cash equivalent.
Description of Accounting Policy for Financial Instruments	(g) Financial instruments (1) Financial assets (policy applicable from January 1, 2018) (i) Classification of financial assets The Company classifies financial assets into the following categories: financial assets at amortized cost, financial assets at fair value through other comprehensive income and financial assets at fair value through profit or loss. When, and only when, the Company changes its business model for managing financial assets it shall reclassify all affected financial assets. a. Financial assets at amortized cost A financial asset is measured at amortized cost if it meets both of the following conditions and is not designated as measured at fair value through profit or loss: i. it is held within a business model whose objective is to hold financial assets to collect contractual cash flows; and ii. its contractual terms give rise on specified dates to cash flows that are solely payments of principal and interest on the principal amount outstanding. Such financial assets are initially recognized at fair value, plus any directly attributable transaction costs. Subsequently, these assets are measured at amortized cost using the effective interest method, less any impairment losses. Interest income, foreign exchange gains and losses, and recognition (reversal) of impairment losses, are recognized in profit or loss. b. Financial assets at fair value through other comprehensive income On initial recognition, the Company is able to make an irrevocable election to present subsequent changes in the fair value of investments in equity instruments that is not held for trading in other comprehensive income. This election is made on an instrument-by-instrument basis. Such financial assets are initially recognized at fair value, plus any directly attributable transaction costs. Subsequent to initial recognition, they are measured at fair value and changes therein are recognized in other comprehensive income and accumulated in equity － Dividends on investments in equity instruments are recognized on the date that the Company’s right to receive the dividends is established. c. Financial assets at fair value through profit or loss All financial assets not classified as at amortized cost or at fair value through other comprehensive income as described above are measured at fair value through profit or loss. This includes all derivative financial assets. Such financial assets are initially recognized at fair value, and attributable transaction costs are recognized in profit or loss as incurred. Subsequent to initial recognition, they are measured at fair value and changes therein are recognized in profit or loss. (ii) Impairment of financial assets The Company recognizes loss allowances for expected credit losses on financial assets at amortized cost, including cash and cash equivalents, receivables, refundable deposits and other financial assets, etc., and contract assets. Loss allowances for financial assets are deducted from the gross carrying amount of the assets. The recognition or reversal of the loss allowance is recognized in profit or loss. The expected credit loss is the weighted average of credit losses with the respective risks of a default occurring on the financial instrument as the weights. The Company measures the loss allowance for a financial instrument at an amount equal to lifetime expected credit losses, except for the financial instrument that is determined to have low credit risk at the reporting date and the credit risk thereof has not increased significantly since initial recognition, which is measured at an amount equal to the 12-month expected credit losses. For trade receivables and contract assets, t When determining whether the credit risk of a financial asset has increased significantly since initial recognition, the Company considers reasonable and supportable information that is relevant. This includes both qualitative and quantitative information and analysis, based on the Company’s historical experience and credit assessment as well as forward-looking information. In the circumstance that a financial asset is past due or the borrower is unlikely to pay its credit obligations to the Company in full, the Company considers the credit risk on that financial asset has significantly increased, or further, to be in default. At each reporting date, the Company assesses whether financial assets at amortized cost are credit-impaired. A financial asset is “credit-impaired” when one or more events that have a detrimental impact on the estimated future cash flows of the financial asset have occurred. (iii) De-recognition of financial assets The Company derecognizes financial assets when the contractual rights to the cash flows from the asset expire, or when the Company transfers substantially all the risks and rewards of ownership of the financial assets to another entity. (2) Financial assets (policy applicable before January 1, 2018) (i) Classification of financial assets The Company classifies financial assets into the following categories: financial assets at fair value through profit or loss, receivables and available-for-sale financial assets. a. Financial assets at fair value through profit or loss The Company has certain financial assets to hedge its exposure to foreign exchange risk arising from operating and financing activities. When a financial asset is not effective as a hedge, the Company accounts for it as a financial asset at fair value through profit or loss. b. Available-for-sale financial assets Available-for-sale financial assets are non-derivative financial assets that are either designated as available-for-sale or are not classified as receivables or financial assets at fair value through profit or loss. Available-for-sale financial assets are recognized initially at fair value, plus any directly attributable transaction cost. Subsequent to initial recognition, they are measured at fair value and changes therein, other than impairment losses, dividend income and foreign currency differences related to monetary financial assets, are recognized in other comprehensive income and presented within equity in unrealized gains (losses) on available-for-sale financial assets. When an investment is derecognized, the cumulative gain or loss in equity is reclassified to profit or loss. A regular way, purchase or sale of financial assets shall be recognized and derecognized, as applicable, using trade date accounting. Investments in equity instruments that do not have a quoted market price in an active market, and whose fair value cannot be reliably measured, are carried at their cost less any impairment losses. Cash dividends on equity instruments are recognized in profit or loss on the date that the Company’s right to receive dividends is established. c. Receivables Receivables are financial assets with fixed or determinable payments that are not quoted in an active market. Receivables comprise trade receivables and other receivables. Such assets are recognized initially at fair value, plus any directly attributable transaction costs. Subsequently, receivables are measured at amortized cost using the effective interest method, less any impairment. If the effect of discounting is immaterial, the short-term receivables are measured at the original amount. (ii) Impairment of financial assets Financial assets not measured at fair value through profit or loss are assessed at each reporting date for indicators of impairment. Financial assets are considered to be impaired if an objective evidence indicates that, as a result of one or more events that occurred after the initial recognition of the financial asset, the estimated future cash flows of those assets have been negatively impacted. When an available-for-sale equity security is considered to be impaired, cumulative gains or losses previously recognized in other comprehensive income are reclassified to profit or loss. Such impairment losses are not reversed through profit or loss. However, any subsequent recovery in the fair value of an impaired available-for-sale equity security is recognized in other comprehensive income and accumulated in other components of equity. For receivables, the Company first assesses whether objective evidence of impairment exists that are individually significant. If there is objective evidence that an impairment loss has occurred, the amount of impairment loss is assessed individually. For receivables other than those aforementioned, the Company groups those assets and collectively assesses them for impairment. An impairment loss for trade receivables is reflected in an allowance account against the receivables. When it is determined a receivable is uncollectible, it is written off from the allowance account. If any subsequent recovery of receivable previously written off can be related objectively to an event occurring after the impairment loss was recognized, it is credited against the allowance account and recognized in profit or loss. For equity instruments without a quoted market price in an active market, the objective evidence of impairment includes the investees’ financial information, current operating result, future business plans and relevant industry and public market information. An impairment loss for this kind of equity instruments is reduced from the carrying amount and any impairment loss recognized is not reversed through profit or loss in subsequent periods. Bad debt expenses and reversal of allowance for doubtful debts for trade receivables are recognized in general and administrative expenses while impairment losses and reversal of impairment for financial assets other than receivables are recognized in other gains and losses. (iii) De-recognition of financial assets The Company derecognizes financial assets when the contractual rights to the cash inflow from the asset expire, or when the Company transfers substantially all the risks and rewards of ownership of the financial assets to another entity. On de-recognition of a financial asset in its entirety, the difference between the carrying amount and the sum of the consideration received or receivable and any cumulative gain or loss that had been recognized in other comprehensive income is recognized in profit or loss. (3) Financial liabilities (i) Classification of financial liabilities The Company classifies financial liabilities into the following categories: financial liabilities at fair value through profit or loss and other financial liabilities. a. Financial liabilities at fair value through profit or loss The Company designates financial liabilities as held for trading for the purpose of hedging exposure to foreign exchange risk arising from operating and financing activities. When a financial liability is not effective as a hedge, the Company accounts for it as a financial liability at fair value through profit or loss. The Company designates financial liabilities, other than the one mentioned above, as at fair value through profit or loss at initial recognition. Attributable transaction costs are recognized in profit or loss as incurred. Financial liabilities in this category are subsequently measured at fair value and changes therein, which takes into account any interest expense, are recognized in profit or loss. b. Other financial liabilities Financial liabilities not classified as held for trading, or not designated as at fair value through profit or loss (including loans and borrowings, trade and other payables), are measured at fair value, plus any directly attributable transaction cost at the time of initial recognition. Subsequent to initial recognition, they are measured at amortized cost calculated using the effective interest method, except for insignificant recognition of interest expense from short-term borrowings and payables. Interest expense not capitalized as an asset cost is recognized in profit or loss. (ii) De-recognition of financial liabilities The Company derecognizes financial liabilities when the contractual obligation has been discharged, cancelled or expired. The difference between the carrying amount and the consideration paid or payable, including any non-cash assets transferred or liabilities assumed is recognized in profit or loss. (4) Offsetting of financial assets and liabilities The Company presents financial assets and liabilities on a net basis in the consolidated statement of financial position when the Company has the legally enforceable rights to offset, and intends to settle such financial assets and liabilities on a net basis or to realize the assets and settle the liabilities simultaneously.
Description of Accounting Policy for Measuring Inventories	(h) Inventories The cost of inventories includes all necessary expenditures and charges for bringing the inventory to a stable, useable and marketable condition and location. The production overhead is allocated to finished goods and work in progress based on the normal capacity of the production facilities. Subsequently, inventories are measured at the lower of cost and net realizable value. Cost is determined using the weighted-average method. Net realizable value is calculated based on the estimated selling price less all estimated costs of completion and the estimated costs necessary to make the sale.
Description of Accounting Policy for Non-Current Assets or Disposal Groups Classified as Held for Sale	(i) Noncurrent assets held for sale Noncurrent assets are classified as held for sale when their carrying amounts are expected to be recovered primarily through sale rather than through continuing use. Such noncurrent assets must be available for immediate sale in their present condition and the sale is highly probable within one year. When classified as held for sale, the assets are measured at the lower of their carrying amount and fair value less costs to sell. Impairment losses on initial classification as held for sale and subsequent gains or losses on re-measurement are recognized in profit or loss. However, subsequent gains are not recognized in excess of the cumulative impairment loss that has been recognized. When intangible assets and property, plant and equipment are classified as held for sale, they are no longer amortized or depreciated. In addition, once an equity-accounted investee is classified as held for sale, it is no longer equity accounted.
Description of Accounting Policy for Investment in Associates and Joint Ventures	(j) Investments in associates and joint ventures Associates are those entities in which the Company has the power to exercise significant influence, but not control or joint control, over their financial and operating policies. Joint venture is a joint arrangement whe reby the Company and other parties agreed to share the control of the arrangement, and have rights to the net assets of the arrangement. Unanimous consent from the parties sharing control is required when making decisions for the relevant activities of the arrangement. Investments in associates or joint ventures are accounted for using the equity method and are recognized initially at cost. The cost of the investment includes transaction costs. The consolidated financial statements include the Company’s share of the profit or loss and other comprehensive income of associates or joint ventures. When an associate or a joint venture incurs changes in its equity not derived from profit or loss and other comprehensive income, the Company recognizes all the equity changes in proportion to its ownership interest in the associate or joint venture as capital surplus provided that the ownership interest in the associate or joint venture remains unchanged. The difference between acquisition cost and fair value of associates’ or joint ventures’ identifiable assets and liabilities as of the acquisition date is accounted for as goodwill. Goodwill is included in the original investment cost of acquired associates or joint ventures and is not amortized. If the fair value of identified assets and liabilities is in excess of acquisition cost, the remaining excess over acquisition cost is recognized as a gain in profit or loss. The Company discontinues the use of the equity method from the date when its investment ceases to be an associate or a joint venture, and then measures the retained interests at fair value at that date. The difference between the carrying amount of the investment at the date the equity method was discontinued and the fair value of the retained interests along with any proceeds from disposing of a part interest in the associate or joint venture is recognized in profit or loss. Moreover, the Company accounts for all amounts previously recognized in other comprehensive income in relation to that investment on the same basis as would be required if the investee had directly disposed of the related assets or liabilities. When the Company subscribes for additional shares in an associate or a joint venture at a percentage different from its existing ownership percentage, the resulting carrying amount of the investment differs from the amount of the Company’s proportionate interest in the net assets of the associate or joint venture. The Company records such a difference as an adjustment to investments with the corresponding amount charged or credited to capital surplus. If the capital surplus arising from investment accounted for under the equity method in associates or joint ventures is insufficient to offset with the said corresponding amount, the differences will be charged or credited to retained earnings. If the Company’s ownership interest in an associate or a joint venture is reduced due to disposal of or disproportionate subscription to the shares, but the Company continues to apply the equity method, the Company shall reclassify to profit or loss the proportion of the gain or loss that had previously been recognized in other comprehensive income relating to that reduction in ownership interest on the same basis as would be required if the investee had directly disposed of the related assets or liabilities. At the end of each reporting period, if there is any indication of impairment, the entire carrying amount of the investment including goodwill is tested for impairment as a single asset, by comparing its recoverable amount with its carrying amount. An impairment loss recognized forms part of the carrying amount of the investment in associates or joint ventures. Accordingly, any reversal of that impairment loss is recognized to the extent that the recoverable amount of the investment subsequently increases. Profits and losses resulting from the transactions between the Company and associates or joint ventures are recognized in the Company’s consolidated financial statements only to the extent of interests in the associate or joint venture that are not related to the Company. When the Company’s share of losses exceeds its interest in an associate or a joint venture, the carrying amount of that interest, including any long-term investments that form part thereof, is reduced to zero, and the recognition of further losses is discontinued except to the extent that the Company has a legal or constructive obligation, or has made payments on behalf of the investee.
Description of Accounting Policy for Investment Property	(k) Investment property Investment property is the property held either to earn rental income or for capital appreciation or for both, but not for sale in the ordinary course of business, use in the production or supply of goods or services or for administrative purposes. Investment property is measured at cost on initial recognition. Subsequent to initial recognition, investment properties are measured using the cost model. Depreciation is charged and recognized in profit or loss based on the depreciable amount. Depreciation methods, useful lives and residual values are in accordance with the policy of property, plant and equipment. Cost includes expenditure that is directly attributable to the acquisition of the investment property. An investment property is reclassified to property, plant and equipment at its carrying amount when the use of the investment property changes.
Description of Accounting Policy for Property, Plant and Equipment	(l) Property, plant and equipment (1) Recognition and measurement Items of property, plant and equipment are measured at cost less accumulated depreciation and accumulated impairment losses. Cost includes expenditure that is directly attributed to the acquisition of the asset, any cost directly attributable to bringing the asset to the location and condition necessary for it to be capable of operating in the manner intended by management, the initial estimate of the costs of dismantling and removing the item and restoring the site on which it is located, and any borrowing cost that is eligible for capitalization. The cost of the software is capitalized as part of the equipment if the purchase of the software is necessary for the equipment to be capable of operating. When part of an item of property, plant and equipment with a cost that is significant in relation to the total cost of the item and the useful life or the depreciation method of the significant part is different from another significant part of that same item, it is accounted for as a separate item (significant component) of property, plant and equipment. The gain or loss arising from the derecognition of an item of property, plant and equipment is determined as the difference between the net disposal proceeds, if any, and the carrying amount of the item, and is recognized in profit or loss. (2) Subsequent costs Subsequent expenditure is capitalized only when it is probable that the future economic benefits associated with the expenditure will flow to the Company and the cost of the item can be measured reliably. Ongoing repairs and maintenance expenses are recognized in profit or loss as incurred. (3) Depreciation Depreciation is determined by depreciable amount allocated over the estimated useful lives of the respective assets, considering significant components of an individual asset on a straight-line basis. If a component has a useful life that is different from the remainder of that asset, that component is depreciated separately. Depreciation is recognized in profit or loss. Leased assets are depreciated over their useful lives if it is reasonably certain that the Company will obtain ownership by the end of the lease term. Otherwise, leased assets are depreciated over the shorter of the lease term and their useful lives. Except for land, which is not depreciated, the estimated useful lives of the assets are as follows: (i) Buildings: 20~50 years (ii) Machinery and equipment: 3~10 years (iii) Other equipment: 3~6 years Depreciation methods, useful lives, and residual values are reviewed at each annual reporting date and, if necessary, adjusted as appropriate. Any changes therein are accounted for as changes in accounting estimates. (4) Reclassification to investment property A property is reclassified to investment property at its carrying amount when the use of the property changes from owner-occupied to investment purpose.
Description of Accounting Policy for Long Term Prepaid Rent	(m) Long-term prepaid rent (policy applicable before January 1, 2019) Long-term prepaid rent is for the right to use of land (classified as other noncurrent assets), which is amortized over the shorter of economic useful life or the covenant period on a straight-line basis.
Description of Accounting Policy for Leases	(n) Leases (1) Leases (policy applicable from January 1, 2019) (i) Identifying a lease A contract is, or contains, a lease when all the following conditions are satisfied: a. the contract involves the use of an identified asset, and the supplier does not have a substantive right to substitute the asset; and b. the Company has the right to obtain substantially all of the economic benefits from use of the identified asset throughout the period of use; and c. the Company has the right to direct the use of the identified asset throughout the period of use. (ii) As a lessee Payments for leases of low-value assets and short-term leases are recognized as expenses on a straight-line basis during the lease term for which the recognition exemption is applied. Except for leases described above, a right-of-use asset and a lease liability shall be recognized for all other leases at the lease commencement date. The Company recognizes a right-of-use asset and a lease liability at the lease commencement date. The lease liability is initially measured at the present value of the lease payments (including fixed payments and variable lease payments that depend on an index or a rate), discounted using the lessee’s incremental borrowing rate. The right-of-use asset is initially measured at cost, which comprises the initial amount of the lease liability, adjusted for any lease payments made at or before the commencement date, less any lease incentives received, plus any initial direct costs incurred and an estimate of costs to be incurred in restoring the underlying asset. The right-of-use asset is subsequently depreciated using the straight-line method over the shorter of the useful life of the right-of-use asset or the lease term. The lease liability is subsequently measured at amortized cost using the effective interest method. It is remeasured (i) if there is a change in the lease term; (ii) if there is a change in future lease payments arising from a change in an index or a rate; (iii) if there is a change in the amounts expected to be payable under a residual value guarantee; or (iv) if the Company changes its assessment of whether it will exercise a purchase, extension or termination option. When the lease liability is remeasured in the circumstances aforementioned, a corresponding adjustment is made to the carrying amount of the right-of-use asset. However, if the carrying amount of the right-of-use asset is reduced to zero, any remaining amount of the remeasurement is recognized in profit or loss. Moreover, the lease liability is remeasured when lease modifications occur that decrease the scope of the lease. The Company accounts for the remeasurement of the lease liability by decreasing the carrying amount of the right-of-use asset to reflect the partial or full termination of the lease, and recognizes in profit or loss any gain or loss relating to the partial or full termination of the lease. (iii) As a lessor Lease income from an operating lease is recognized in profit or loss on a straight-line basis over the lease term. Initial direct costs incurred in negotiating and arranging an operating lease are added to the carrying amount of the asset leased to others and recognized as an expense on a straight-line basis over the lease term. (2) Leases (policy applicable before January 1, 2019) (i) Lessor Lease income from an operating lease is recognized in profit or loss on a straight-line basis over the lease term. Initial direct costs incurred in negotiating and arranging an operating lease are added to the carrying amount of the leased asset and recognized as an expense on a straight-line basis over the lease term. (ii) Lessee Payments made under operating lease (excluding insurance and maintenance expenses) are recognized in profit or loss on a straight-line basis over the term of the lease.
Description of Accounting Policy for Intangible Assets and Goodwill	(o) Intangible assets (1) Goodwill Goodwill is recognized when the purchase price exceeds the fair value of identifiable net assets acquired in a business combination. Goodwill is measured at cost less accumulated impairment losses. Equity-method goodwill is included in the carrying amounts of the equity investments. The impairment losses for the goodwill within the equity-accounted investees are accounted for as deductions of carrying amounts of investments in equity-accounted investees. (2) Research and development During the research phase, activities are carried out to obtain and understand new scientific or technical knowledge. Expenditures during this phase are recognized in profit or loss as incurred. Expenditure arising from development is capitalized as an intangible asset when the Company demonstrates all of the following: (i) the technical feasibility of completing the intangible asset so that it will be available for use or sale; (ii) its intention to complete the intangible asset and use or sell it; (iii) its ability to use or sell the intangible asset; (iv) the probability that the intangible asset will generate probable future economic benefits; (v) the availability of adequate technical, financial and other resources to complete the development and to use or sell the intangible asset; and (vi) its ability to measure reliably the expenditure attributable to the intangible asset during its development. Development expenditure which fails to meet the criteria for recognition as an intangible asset is reflected in profit or loss when incurred. Capitalized development expenditure is measured at cost less accumulated amortization and any accumulated impairment losses. (3) Other intangible assets Other intangible assets acquired are measured at cost less accumulated amortization and any accumulated impairment losses. (4) Subsequent expenditure Subsequent expenditure is capitalized only when it increases the future economic benefits embodied in the specific asset to which it relates. All other expenditure, including expenditure on internally generated goodwill and brands, is recognized in profit or loss as incurred. (5) Amortization The depreciable amount of an intangible asset is the cost less its residual value. Other than goodwill and intangible assets with indefinite useful life, an intangible asset with a finite useful life is amortized over 3 to 20 years using the straight-line method from the date that the asset is made available for use. The amortization charge is recognized in profit or loss. The residual value, amortization period, and amortization method are reviewed at least annually at each annual reporting date, and any changes therein are accounted for as changes in accounting estimates.
Description of Accounting Policy for Impairment of Non-Financial Assets	(p) Impairment – non-financial assets Other than inventories, deferred tax assets and noncurrent assets held for sale, the carrying amounts of the Company’s investment property measured at cost and other long-term non-financial assets (property, plant and equipment, right-of-use assets and other intangible assets with finite useful lives), are reviewed at the reporting date to determine whether there is any indication of impairment. When there is an indication of impairment exists for the aforementioned assets, the recoverable amount of the asset is estimated. If it is not possible to estimate the recoverable amount of an individual asset, the Company estimates the recoverable amount of CGU to which the asset has been allocated to. In performing an impairment test for other long-term non-financial assets, the estimated recoverable amount is evaluated in terms of an asset or a CGU. Any excess of the carrying amount of the asset or its related CGU over its recoverable amount is recognized as an impairment loss. The recoverable amount of an asset or a CGU is the higher of its fair value less costs of disposal and its value in use. If there is evidence that the accumulated impairment loss of an asset other than goodwill and intangible assets with indefinite useful lives in prior years no longer exists or has decreased, the amount previously recognized as an impairment loss is reversed, and the carrying amount of the asset or CGU is increased to the revised estimate of its recoverable amount. The increased carrying amount shall not exceed the carrying amount that would have been determined (net of depreciation or amortization) had no impairment loss been recognized for the asset in prior years. For goodwill and intangible assets with indefinite useful lives or that are not yet available for use, are required to be tested for impairment at least annually. Any excess of the carrying amount of the asset over its recoverable amount is recognized as an impairment loss. For the purpose of impairment test, goodwill acquired in a business combination is allocated to CGUs that are expected to benefit from the synergies of the combination. If the recoverable amount of a CGU is less than its carrying amount, the difference is allocated first to reduce the carrying amount of any goodwill allocated to the unit, then the carrying amounts of the other assets in the unit on a pro rata basis. The impairment loss recognized on goodwill is not reversed in a subsequent period.
Description of Accounting Policy for Provisions	(q) Provisions A provision is recognized when the Company has a present obligation arising from a past event, it is probable that the Company will be required to make an outflow of resources embodying economic benefits to settle the obligation, and the amount of the obligation can be estimated reliably. Provisions are determined by discounting the expected future cash flows at a pre-tax rate that reflects the current market assessments of the time value of money and the risks specific to the liability. The unwinding of the discount is recognized as interest expense. (1) Warranties A provision for warranties is recognized when the underlying products or services are sold. The provision is weighting factors based on historical experience of warranty claims rate and other possible outcomes against their associated probabilities. (2) Decommissioning obligation The Company is subject to decommissioning obligations related to certain items of property, plant and equipment. Such decommissioning obligations are primarily attributable to clean-up costs, including deconstruction, transportation, and recover costs. The unwinding of the discount based on original discount rate is recognized in profit or loss as interest expense over the periods with corresponding increase in the carrying amounts of the accrued decommissioning costs. The carrying amount of the accruals at the end of the assets’ useful lives is the same as the estimated decommissioning costs. (3) Onerous contracts A provision for onerous contracts is recognized when the expected benefits to be derived by the Company from a contract are lower than the unavoidable cost of meeting its obligations under the contract. The provision is measured at the present value of the lower of the expected cost of terminating the contract and the expected net cost of continuing with the contract. Before a provision is established, the Company recognizes any impairment loss on the assets associated with that contract. (4) Loss contingencies Management periodically assesses the obligation of all litigation and claims and relative legal costs. Provision for loss contingencies arising from claims, assessments, litigation, fines, and penalties and other sources are recognized when it is probable the present obligation as a result of a past event will result in an outflow of resources and the amount can be reasonably estimated. Provisions recognized are the best estimates of the expenditure for settling the present obligation at each reporting date.
Description of Accounting Policy for Treasury Shares	(r) Treasury shares Where the Company repurchases its common stock that has been issued, the consideration paid, including all directly attributable costs is recorded as treasury share and deducted from equity. When treasury share is reissued, the excess of sales proceeds over cost is accounted for as capital surplus – If treasury share is retired, the weighted-average cost of the retired treasury share is written off against the par value and the capital surplus premium, if any, of the stock retired on a pro rata basis. If the weighted-average cost written off exceeds the sum of the par value and the capital surplus premium, the difference is accounted for as a reduction of capital surplus – – –
Description of Accounting Policy For Revenue From Contracts With Customers	(s) Revenue from contracts with customers (policy applicable from January 1, 2018) Revenue is measured based on the consideration that the Company expects to be entitled in the transfer of goods or services to a customer. The Company recognizes revenue when it satisfies a performance obligation by transferring control over a product or service to a customer. The following is a description of the Company’s major revenues: (1) Sales of goods Revenue is recognized when the control over a product has been transferred to the customer. The transfer of control refers to the product has been delivered to and accepted by the customer without remaining performance obligations from the Company. Delivery occurs when the product has been shipped to the specified location and the risk of loss over the product has been transferred to the customer, as well as when the product has been accepted by the customer according to the terms of sales contract, or when the Company has objective evidence that all criteria for acceptance have been satisfied. For certain contracts with volume discounts offer to customers, revenue is recognized on a net basis of contract price less estimated volume discounts, and only to the extent that it is highly probable that a significant reversal will not occur. The amount of volume discounts is estimated based on the expected value with reference to the historical experience, and is recorded as refund liability (presented under other current liabilities). Trade receivable is recognized when the Company is entitled for unconditional right to receive payment upon delivery of goods to customers. The consideration received in advance from the customer according to the sales contract but without delivery of goods is recognized as a contract liability, for which revenue is recognized when the control over the goods is transferred to the customer. The Company provides standard warranties for goods sold and has obligation to refund payments for defective goods, in which the Company has recognized provisions for warranties to fulfill the obligation. Refer to note 25 for further details. (2) Construction contracts For construction contracts, revenue is recognized progressively based on the progress towards complete satisfaction of contract activities, and only to the extent that it is highly probable that a significant reversal in the amount of cumulative revenue recognized will not occur. If the Company cannot reasonably measure its progress towards complete satisfaction of performance obligations in accordance with the construction contracts, revenue is recognized only to the extent of contract costs incurred that it is expected to be recoverable. The consideration is paid by the customer according to the agreed payment terms. The excess of the amount that has been recognized as revenue over the amount that the Company has issued a bill is recognized as a contract asset. When the entitlement to the payment becomes unconditional, the contract asset is transferred to receivables. A contract liability is recognized for an advance consideration that the Company has billed to customers arising from construction contracts. When the construction is completed and accepted by the customers, the contract liability is transferred to revenue. If there are changes in circumstances, the estimates of revenue, cost and the progress towards complete satisfaction of contract will be amended. Any changes therein are recognized in profit or loss during the period in which the changes and amendments are made. The Company provides standard warranties for construction contracts and has recognized provisions for warranties to fulfill the obligation. Refer to note 25 for further details. (3) Financing components The Company expects that the length of time when the Company transfers the goods or services to the customer and when the customer pays for those goods or services will be less than one year. Therefore, the amount of consideration is not adjusted for the time value of money.
Description of Accounting Policy for Recognition of Revenue	(t) Revenue recognition (1) Goods sold (policy applicable before January 1, 2018) Revenue from the sale of goods in the course of ordinary activities is measured at the fair value of the consideration received or receivable, net of returns, trade discounts and volume rebates. Revenue is recognized when the significant risks and rewards of ownership have been transferred to the customer, recovery of the consideration is probable, the associated costs and possible return of goods can be estimated reliably, there is no continuing management involvement with the goods, and the amount of revenue can be measured reliably. If it is probable that discounts will be granted and the amount can be measured reliably, then the discount is recognized as a reduction of revenue as the sales are recognized. The timing of the transfers of risks and rewards varies depending on the individual terms of the sales agreement. (2) Government grants (i) Grants for compensating the research and development expenditures Grants that compensate the Company for research and development expenditures are recognized in profit or loss on a systematic basis in the periods in which the expenses are recognized. (ii) Grants related to the purchase of assets Grants related to the purchase of assets are set up as deferred income and are recognized in profit or loss on a systematic basis over the useful life of the assets. (iii) Other grants Other grants from government that becomes receivable as compensation for expenses or losses already incurred or for the purpose of giving immediate financial support to the Company with no future related costs are recognized in profit or loss of the period in which it becomes receivable.
Description of Accounting Policy for Employee Benefits	(u) Employee benefits (1) Defined contribution plans Obligations for contributions to defined contribution pension plans are recognized as an employee benefit expense in profit or loss in the periods during which services are rendered by employees. (2) Defined benefit plans The Company’s net obligation in respect of defined benefit pension plans is calculated separately for each benefit plan by estimating the amount of future benefit that employees have earned in the current and prior periods, discounting that amount and deducting the fair value of any plan assets. Discount rate is determined by reference to the yield rate of Taiwan government bonds at the reporting date. The calculation of defined benefit obligations is performed annually by a qualified actuary using the Projected Unit Credit Cost Method. Remeasurements of the net defined benefit liability (asset) which comprise actuarial gains and losses, the return on plan assets (excluding interest) and the effect of the asset ceiling (if any, excluding interest), are recognized in other comprehensive income in the period in which they occur, and which then are reflected in retained earnings and will not be reclassified to profit or loss. (3) Short-term employee benefits Short-term employee benefit obligations, which are due to be settled within twelve months are measured on an undiscounted basis and are expensed as the related service is provided. The expected cost of cash bonus or profit-sharing plans, which is anticipated to be paid within one year, are recognized as a liability when the Company has a present legal or constructive obligation to pay this amount as a result of past service provided by the employee, and the obligation can be estimated reliably.
Description of Accounting Policy for Share-Based Payment Transactions	(v) Share-based payment arrangements The compensation cost of employee share-based payment arrangements is measured based on the fair value at the date on which they are granted. The compensation cost is recognized, together with a corresponding increase in equity, over the periods in which the employees become unconditionally entitled to the awards. The amount recognized as an expense is adjusted to reflect the number of awards whose related service and non-market performance conditions are expected to be met, such that the amount ultimately recognized as an expense is based on the number of awards that meet the related service and non-market performance conditions at the vesting date. For share-based payment awards with non-vesting conditions, the grant-date fair value of the share-based payment is measured to reflect such conditions, and there is no true-up for differences between expected and actual outcomes.
Description of Accounting Policy for Income Tax	(w) Income taxes Income tax expense comprises current and deferred taxes. (1) Current taxes Current taxes comprise the expected tax payable or receivable on the taxable income or losses for the year and any adjustments to tax payable or receivable in respect of previous years. It is measured using the statutory tax rate or the actual legislative tax rate at the reporting date. In accordance with the ROC Income Tax Act, undistributed earnings from the companies located in the Republic of China, if any, is subject to an additional surtax. The surtax on unappropriated earnings is recognized during the period the earnings arise and adjusted to the extent that distributions are approved by the shareholders in the following year. (2) Deferred taxes Deferred taxes are recognized in respect of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. Deferred tax liabilities are recognized for temporary difference of future taxable income. Deferred tax assets are recognized for unused tax losses, unused tax credits and deductible temporary differences to the extent that it is probable that future taxable profits will be available against which they can be utilized. Deferred tax assets are reviewed at annual reporting date, by considering global economic environment, industry environment, statutory tax deduction years and projected future taxable income, and reduced to the extent that it is no longer probable that the related tax benefit will be realized. Deferred tax assets which originally not recognized is also reviewed at annual reporting date and recognized to the extent that it is probable that future taxable profits will be available to allow all or part of the deferred tax asset to be recovered. Deferred taxes liabilities for taxable temporary differences related to investments in subsidiaries, associates and joint arrangements are recognized, unless the Company is able to control the timing of the reversal of the taxable temporary differences and it is probable that they will not reverse in the foreseeable future. Deferred tax is measured at the tax rates that are expected to be applied to temporary differences when the reverse, using the statutory tax rate or the actual legislative tax rate on the reporting date. Deferred tax assets and liabilities are offset only if certain criteria are met. Current taxes and deferred taxes are recognized in profit or loss except to the extent that it relates to items recognized directly in equity or other comprehensive income.
Description of Accounting Policy for Business Combinations	(x) Business combinations The consideration transferred in the acquisition is measured at fair value, as are identifiable net assets acquired. Goodwill is measured as the excess of the aggregate of the fair value of consideration transferred and the amount of any non-controlling interests in the acquiree over the net identifiable assets acquired and liabilities assumed. If the fair value of the net assets acquired is in excess of the aggregate consideration transferred and the amount of any non-controlling interests in the acquiree, after reassessing all of the assets acquired and all of the liabilities assumed being properly identified, the difference is recognized in profit or loss as a gain on bargain purchase. Acquisition-related costs are expensed as incurred, except that the costs are related to the issue of debt or equity instruments. Non-controlling interests in an acquiree that are present ownership interests and entitle their holders to a proportionate share of the entity’s net assets in the event of liquidation are measured, on a case-by-case basis, at either fair value or the present ownership instruments’ proportionate share in the recognized amounts of the acquiree’s net identifiable assets. All other components of non-controlling interests shall be measured at their acquisition-date fair values, unless another measurement basis is required by IFRSs. Any contingent consideration included in the consideration transferred is recognized at fair value at the date of acquisition. Subsequent changes to the fair value of the contingent consideration during the measurement period shall adjust to the cost of the acquisition and the resulting goodwill retrospectively. An adjustment made during the measurement period is to reflect additional information obtained by the Company about facts and circumstances that existed as of the acquisition date. The measurement period shall not exceed one year from the acquisition date. The accounting treatment for those changes to the fair value of the contingent consideration that are not measurement period adjustments is depending on the classification of the contingent consideration. If the contingent consideration is classified as equity, it is not remeasured and the subsequent settlement is accounted for within equity. Otherwise, other contingent consideration is remeasured at fair value at each reporting date and subsequent changes in the fair value are recognized in profit or loss.
Description of Accounting Policy for Earnings (Loss) Per Share	(y) Earnings (loss) per share Basic earnings (loss) per share is computed by dividing profit or loss attributable to the shareholders of AUO by the weighted-average number of common shares outstanding during the period. In computing diluted earnings per share, profit or loss attributable to the shareholders of AUO and the weighted-average number of common shares outstanding during the period are adjusted for the effects of dilutive potential common stock, assuming dilutive share equivalents had been issued. The weighted-average outstanding shares are retroactively adjusted for the effects of stock dividends transferred from retained earnings or capital surplus to common stock.
Description of Accounting Policy for Segment Reporting	(z) Operating segments An operating segment is a component of an entity: (1) that engages in business activities from which it may earn revenue and incur expenses (including revenues and expenses relating to transactions with other components of the same entity), (2) whose operating results are reviewed regularly by the entity’s chief operating decision maker (“CODM”) to make decisions pertaining to the allocation of resources to the segment and to assess its performance, and (3) for which discrete financial information is available. Management has determined that the Company has two operating segments: display and energy (formerly named “solar”). The accounting policies for the operating segments are the same as those used in the preparation of the consolidated financial statements of the Company. Segment profit (loss) is determined by deducting selling, administrative and research and development expenses from gross profit. Segment profit (loss) excludes long-lived asset impairments, gains and losses on disposal of assets, litigation provisions, foreign currency exchange gains or losses, finance cost, income taxes, share of profit (loss) from equity-accounted investees, and other miscellaneous income and expenses. The CODM does not receive asset and liability information by operating segment. Consequently, no operating segment asset and liability information is disclosed. Geographic net revenue information is based upon the location of customers placing orders.

Changes in Significant Accoun_2

Changes in Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2019
Disclosure of initial application of standards or interpretations [line items]
Disclosure of Initial Application of Standards or Interpretations	The reconciliation between the lease liabilities recognized and the future minimum lease payments of non-cancellable operating leases on December 31, 2018 is presented as follows: Amounts (in thousands) The future minimum lease payments of non-cancellable operating leases on December 31, 2018 $ 5,942,211 Recognition exemption for short-term leases (43,032 ) Other leases in scope of IFRS 16 125,328 Undiscounted amount on January 1, 2019 $ 6,024,507 Discounted amount using the incremental borrowing rate on January 1, 2019 $ 5,445,818 Finance lease liabilities recognized on December 31, 2018 2,496 Extension of lease that reasonably certain to be exercised 7,241,212 Lease liabilities recognized on January 1, 2019 $ 12,689,526
Initial Application of IFRS16 [member]
Disclosure of initial application of standards or interpretations [line items]
Disclosure of Initial Application of Standards or Interpretations	The following table summarized the impacts of initially applying IFRS 16 on the Company’s assets, liabilities and equity as at January 1, 2019. January 1, 2019 Carrying amount under IAS 17 and related standards and interpretations Adjustments from changes in accounting policies Carrying amount under IFRS 16 (in thousands) Other current assets $ 2,941,598 (6,638 ) 2,934,960 Property, plant and equipment 221,586,475 (1,765 ) 221,584,710 Right-of-use assets - 14,059,544 14,059,544 Other noncurrent assets 5,171,646 (1,364,111 ) 3,807,535 Impacts to total assets $ 12,687,030 Lease liabilities–current $ - 708,167 708,167 Other current liabilities 24,291,532 (931 ) 24,290,601 Lease liabilities–noncurrent - 11,981,359 11,981,359 Other noncurrent liabilities 2,029,651 (1,565 ) 2,028,086 Impacts to total liabilities $ 12,687,030 Impacts to total equity $ -

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Disclosure of Subsidiaries	The consolidated entities were as follows: Name of Investor Name of Subsidiary Main Activities and Location Percentage of Ownership (%) December 31, 2018 December 31, 2019 AUO AU Optronics (L) Corp. (AULB) Holding and trading company (Malaysia) 100.00 100.00 AUO Konly Venture Corp. (Konly) Venture capital investment (Taiwan ROC) 100.00 100.00 AUO Ronly Venture Corp. (Ronly) Venture capital investment (Taiwan ROC) 100.00 100.00 AUO Space Money Inc. (SMI) Sales and leasing of content management system and hardware (Taiwan ROC) 100.00 100.00 AUO U-Fresh Technology Inc. (UTI) Planning, design and development of construction for environmental protection and related project management (Taiwan ROC) 100.00 100.00 AUO ComQi Ltd. (CQIL) Holding company (Israel) 100.00 (1) 100.00 AUO AU Optronics Europe B.V. (AUNL) Sales and sales support of TFT-LCD panels (Netherlands) 100.00 (2) 100.00 AUO, Konly and Ronly Darwin Precisions Corporation (DPTW) Manufacturing, design and sales of TFT-LCD modules, TV set, backlight modules and related parts (Taiwan ROC) 41.05 (3) 41.05 (3) AUO and Konly AUO Crystal Corp. (ACTW) Manufacturing and sales of ingots and solar wafers (Taiwan ROC) 96.02 (4) 100.00 (4) ACTW Sanda Materials Corporation (SDMC) Holding company (Taiwan ROC) 100.00 (5) 100.00 ACTW AUO Crystal (Malaysia) Sdn. Bhd. (ACMK) Manufacturing and sales of solar wafers (Malaysia) 100.00 100.00 SDMC M.Setek Co., Ltd. (M.Setek) Manufacturing and sales of ingots (Japan) 99.9991 99.9991 AULB AU Optronics Corporation America (AUUS) Sales and sales support of TFT-LCD panels (United States) 100.00 100.00 AULB AU Optronics Corporation Japan (AUJP) Sales support of TFT-LCD panels (Japan) 100.00 100.00 Name of Investor Name of Subsidiary Main Activities and Location Percentage of Ownership (%) December 31, 2018 December 31, 2019 AULB AU Optronics Korea Ltd. (AUKR) Sales support of TFT-LCD panels (South Korea) 100.00 100.00 AULB AU Optronics Singapore Pte. Ltd. (AUSG) Holding company and sales support of TFT-LCD panels (Singapore) 100.00 100.00 AULB AU Optronics (Czech) s.r.o. (AUCZ) (6) Assembly of solar modules (Czech Republic) 100.00 100.00 AULB AU Optronics (Shanghai) Co., Ltd. (AUSH) Sales support of TFT-LCD panels (PRC) 100.00 100.00 AULB AU Optronics (Xiamen) Corp. (AUXM) Manufacturing, assembly and sales of TFT-LCD modules (PRC) 100.00 100.00 AULB AU Optronics (Suzhou) Corp., Ltd. (AUSZ) Manufacturing, assembly and sales of TFT-LCD modules (PRC) 100.00 100.00 AULB AU Optronics Manufacturing (Shanghai) Corp. (AUSJ) Manufacturing and assembly of TFT-LCD modules; leasing (PRC) 100.00 100.00 AULB AU Optronics (Slovakia) s.r.o. (AUSK) Repairing of TFT-LCD modules (Slovakia Republic) 100.00 100.00 AULB AFPD Pte., Ltd. (AUST) Manufacturing TFT-LCD panels based on low temperature polysilicon technology (Singapore) 100.00 100.00 AULB AU Optronics (Kunshan) Co., Ltd. (AUKS) Manufacturing and sales of 51.00 51.00 AULB a.u. Vista Inc. (AUVI) Research and development and IP related business (United States) 100.00 100.00 AULB and DPTW BriView (L) Corp. (BVLB) Holding company (Malaysia) 100.00 100.00 AUSG AUO Energy (Tianjin) Corp. (AETJ) (6) Manufacturing and sales of solar modules (PRC) 100.00 - AUSG AUO Green Energy America Corp. (AEUS) Sales support of solar-related products (United States) 100.00 100.00 AUSG AUO Green Energy Europe B.V. (AENL) Sales support of solar-related products (Netherlands) 100.00 100.00 AUXM BriView (Xiamen) Corp. (BVXM) Manufacturing and sales of liquid crystal products and related parts (PRC) 100.00 100.00 AUSH AUO Care Information Tech. (Suzhou) Co., Ltd. (A-Care) Design, development and sales of software and hardware for health care industry (PRC) 100.00 100.00 Name of Investor Name of Subsidiary Main Activities and Location Percentage of Ownership (%) December 31, 2018 December 31, 2019 AUSH U-Fresh Technology (Suzhou) Co., Ltd. (UFSZ) Planning, design and development of construction project for environmental protection and related project management (PRC) 100.00 (7) 100.00 AUSH Edgetech Data Technologies (Suzhou) Corp., Ltd. (EDT) Design and sales of software and hardware integration system and equipment relating to intelligent manufacturing (PRC) 100.00 (7) 100.00 AUSH Mega Insight Smart Manufacturing (Suzhou) Corp., Ltd. (MIS) Development and licensing of software relating to intelligent manufacturing, and related consulting services (PRC) 100.00 (7) 100.00 UFSZ U-Fresh Environmental Technology (Shandong) Co., Ltd. (UFSD) Planning, design and development of construction project for environmental protection and related project management (PRC) - 100.00 (7) CQIL ComQi Holdings Ltd. (CQHLD) Holding company (United Kingdom) 100.00 (1) 100.00 CQHLD ComQi UK Ltd. (CQUK) Sales support of content management system (United Kingdom) 100.00 (1) 100.00 CQHLD ComQi Inc. (CQUS) Sales of content management system and hardware (United States) 100.00 (1) 100.00 CQHLD ComQi Canada Inc. (CQCA) Research and development of content management system (Canada) 100.00 (1) 100.00 CQUS JohnRyan Limited (JRUK) Development and sales of content management system and sales of related hardware (United Kingdom) - 100.00 (7) CQUS JohnRyan Inc. (JRUS) Development and sales of content management system and sales of related hardware (United States) - 100.00 (7) DPTW Darwin Precisions (L) Corp. (DPLB) Holding company (Malaysia) 100.00 100.00 DPTW Forhouse International Holding Ltd. (FHVI) Holding company (BVI) 100.00 100.00 DPTW Force International Holding Ltd. (FRVI) (6) Holding company (BVI) 100.00 - DPTW and FRVI Forefront Corporation (FFMI) Holding company (Mauritius) 100.00 100.00 (6) Name of Investor Name of Subsidiary Main Activities and Location Percentage of Ownership (%) December 31, 2018 December 31, 2019 FHVI Fortech International Corp. (FTMI) Holding company (Mauritius) 100.00 100.00 FHVI Forward Optronics International Corp. (FWSA) Holding company (Samoa) 100.00 100.00 FHVI Prime Forward International Ltd. (PMSA) Holding company (Samoa) 100.00 100.00 FFMI Forhouse Electronics (Suzhou) Co., Ltd. (FHWJ) Manufacturing of motorized treadmills (PRC) 100.00 100.00 FTMI Fortech Electronics (Suzhou) Co., Ltd. (FTWJ) Manufacturing and sales of backlight modules and related parts (PRC) 100.00 100.00 FWSA and FTMI Suzhou Forplax Optronics Co., Ltd. (FPWJ) Manufacturing and sales of precision plastic parts (PRC) 100.00 100.00 PMSA Fortech Electronics (Kunshan) Co., Ltd. (FTKS) Manufacturing and sales of backlight modules and related parts (PRC) 100.00 100.00 DPLB Darwin Precisions (Hong Kong) Limited (DPHK) Holding company (Hong Kong) 100.00 100.00 DPLB Darwin Precisions (Slovakia) s.r.o. (DPSK) Manufacturing and sales of automotive parts (Slovakia Republic) 100.00 100.00 DPHK Darwin Precisions (Suzhou) Corp. (DPSZ) Manufacturing and sales of backlight modules and related parts (PRC) 100.00 100.00 DPHK Darwin Precisions (Xiamen) Corp. (DPXM) Manufacturing and sales of backlight modules and related parts (PRC) 100.00 100.00 BVLB BriView (Hefei) Co., Ltd. (BVHF) Manufacturing and sales of liquid crystal products and related parts (PRC) 100.00 100.00 Note 1: In March 2018, the Company acquired 100% of the shareholdings of CQIL and its subsidiaries (hereinafter referred to as “ComQi”) and therefore, obtained control over ComQi. Refer to note 15 for further details. Note 2: As part of a business restructuring, AULB disposed all of its shareholdings in AUNL to AUO in December 2018. This was treated as an equity transaction as there was no change in control of AUNL by the Company. Note 3: Although the Company did not own more than 50% of the DPTW’s ownership interests, it was considered to have de facto control over the main operating policies of DPTW. As a result, DPTW was accounted for as a subsidiary of the Company. Note 4: As part of a business restructuring, Konly and Ronly successively disposed its shareholdings in ACTW to AUO in December 2018 and February 2019. This was treated as an equity transaction as there was no change in control of ACTW by the Company. Note 5: As part of a business restructuring, AUO, Konly and Ronly disposed all of their shareholdings in SDMC to ACTW during the second quarter of 2018. This was treated as an equity transaction as there was no change in control of SDMC by the Company. Note 6: As of December 31, 2019, AETJ and FRVI were liquidated and AUCZ is still in the process of liquidation. After the liquidation of FRVI, its ownership of FFMI was transferred to DPTW. Note 7: UFSZ was incorporated in February 2018. EDT and MIS were incorporated in August 2018. UFSD was incorporated in May 2019. JRUK and JRUS were incorporated in October 2019.

Cash and Cash Equivalents (Tabl

Cash and Cash Equivalents (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Cash and Bank Balances	December 31, 2018 2019 (in thousands) Cash on hand, demand deposits and checking accounts $ 30,134,051 46,290,722 Time deposits 38,939,198 34,124,011 Government bonds with reverse repurchase agreements 90,047 35,039 $ 69,163,296 80,449,772

Financial Assets and Liabilit_2

Financial Assets and Liabilities at Fair Value through Profit or Loss ("FVTPL") (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Disclosure of Financial Instruments	December 31, 2018 2019 (in thousands) Financial assets mandatorily measured at FVTPL: Foreign currency forward contracts $ 70,074 42,815 Structured deposits 1,639,457 1,478,591 $ 1,709,531 1,521,406 Financial liabilities held for trading: Foreign currency forward contracts $ 22,115 18,859
Schedule of Outstanding Foreign Currency Forward Contracts	As of December 31, 2018 and 2019, the Company’s outstanding foreign currency forward contracts were as follows: December 31, 2018 Contract item Maturity date Contract amount (in thousands) Sell USD / Buy NTD Jan. 2019 USD223,000 / NTD6,858,785 Sell USD / Buy JPY Jan. 2019 – Apr. 2019 USD147,470 / JPY16,493,633 Sell NTD / Buy JPY Jan. 2019 – Mar. 2019 NTD2,054,260 / JPY7,400,000 Sell USD / Buy CNY Jan. 2019 – Jun. 2019 USD87,000 / CNY597,420 December 31, 2018 Contract item Maturity date Contract amount (in thousands) Sell EUR / Buy JPY Jan. 2019 EUR12,000 / JPY1,536,180 Sell EUR / Buy USD Jan. 2019 EUR28,500 / USD32,441 Sell EUR / Buy CZK Jan. 2019 – Mar. 2019 EUR3,240 / CZK84,081 Sell USD / Buy MYR Jan. 2019 – Mar. 2019 USD879 / MYR3,670 Sell CNY / Buy JPY Jan. 2019 – Feb. 2019 CNY60,800 / JPY981,383 Sell USD / Buy SGD Jan. 2019 USD5,793 / SGD7,940 Sell CNY / Buy USD Jan. 2019 – Feb. 2019 CNY853,328 / USD124,000 December 31, 2019 Contract item Maturity date Contract amount (in thousands) Sell USD / Buy NTD Jan. 2020 USD176,600 / NTD5,319,611 Sell USD / Buy JPY Jan. 2020 – Apr. 2020 USD47,292 / JPY5,150,510 Sell USD / Buy CNY Jan. 2020 – Jun. 2020 USD61,500 / CNY432,823 Sell USD / Buy SGD Jan. 2020 – Feb. 2020 USD39,276 / SGD53,372 Sell USD / Buy MYR Jan. 2020 – Mar. 2020 USD703 / MYR2,905 Sell CNY / Buy USD Feb. 2020 – Mar. 2020 CNY1,935,305 / USD276,672 Sell EUR / Buy JPY Jan. 2020 – Feb. 2020 EUR23,000 / JPY2,788,285 Sell HKD / Buy USD Jan. 2020 HKD60,177 / USD7,721

Financial Assets at Fair Valu_2

Financial Assets at Fair Value through Other Comprehensive Income ("FVTOCI") (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Disclosure of Fair Value of Investments in Equity Instruments Designated at Fair Value Through Other Comprehensive Income	December 31, 2018 2019 (in thousands) Investments in equity instruments at FVTOCI: Equity securities – listed stocks $ 6,803,900 7,356,501 Equity securities – non-listed stocks 176,025 188,670 $ 6,979,925 7,545,171

Accounts Receivable, net (Inc_2

Accounts Receivable, net (Including Related and Unrelated Parties) (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Trade Receivables	December 31, 2018 2019 (in thousands) Accounts receivable $ 47,453,087 32,104,912 Less: loss allowance (50,853 ) (17,738 ) $ 47,402,234 32,087,174 Accounts receivable, net $ 44,647,981 30,308,675 Accounts receivable from related parties, net $ 2,754,253 1,778,499
Analysis of Expected Credit Losses for Accounts Receivable	Analysis of expected credit losses which was measured based on the aforementioned method, was as follows: December 31, 2018 Carrying amount of accounts receivable Weighted-average loss rate Loss allowance for lifetime expected credit losses (in thousands) (in thousands) Not past due $ 46,529,408 0.00 % 89 Past due less than 60 days 862,373 0.05 % 439 Past due 61~180 days 11,090 0.98 % 109 Past due over 180 days 475 100 % 475 $ 47,403,346 1,112 December 31, 2019 Carrying amount of accounts receivable Weighted-average loss rate Loss allowance for lifetime expected credit losses (in thousands) (in thousands) Not past due $ 31,061,173 0.00 % 1 Past due less than 60 days 1,010,918 0.00 % 4 Past due 61~180 days 15,233 0.95 % 145 $ 32,087,324 150
Schedule of Loss Allowance for Accounts Receivable	The movement of the loss allowance for accounts receivable was as follows: For the years ended December 31, 2017 (i) Individually assessed for impairment Collectively assessed for impairment 2018 2019 (in thousands) Balance at beginning of the year $ 41,812 62,805 93,053 50,853 Provisions (reversals) charged to (against) expense (28,236 ) 18,396 (24,302 ) (14,543 ) Write-offs (6 ) - (17,985 ) (18,404 ) Effect of changes in foreign currency exchange rates (805 ) (913 ) 87 (168 ) Balance at end of the year $ 12,765 80,288 50,853 17,738 (i) The movement of 2017 was under IAS 39. There were no adjustments for the beginning balance of 2018 on the initial application of IFRS 9.
Schedule of Trade Receivables Factoring	The Company entered into financing facilities with banks to factor certain of its accounts receivable without recourse. As at December 31, 2018, the Company did not sell its accounts receivables to banks. As at December 31, 2019, the Company’s accounts receivables sold and derecognized were as follows: December 31, 2019 Underwriting bank Factoring Amount Amount Principal (in thousands) (in thousands) (in thousands) CTBC bank USD 152,000 USD 18,526 NTD 500,000 See Notes(a)~(d) Taipei Fubon Bank USD 120,000 USD 56,020 NTD 1,500,000 See Notes(a)~(d) DBS Bank USD 154,000 USD 56,730 NTD 1,520,000 See Notes(a)~(d) Bank of Taiwan USD 250,000 USD 15,718 USD 14,000 See Notes(a)~(d) Note (a): Under these facilities, the Company transferred accounts receivable to the respective underwriting banks, which are without recourse subject to the underwriting consents. Note (b): The Company informed its customers pursuant to the respective facilities to make payment directly to the respective underwriting banks. Note (c): As of December 31, 2019, total outstanding receivables after the above transactions, net of fees charged by underwriting banks, of $487,754 thousand was recognized under other current financial assets. In addition, interest rate for the balance of advanced amount as of December 31, 2019 was ranging from 1.07% to 2.44%. Note (d): To the extent of the amount transferred to the underwriting banks, risks of non-collection or potential payment default by customers in the event of insolvency are borne by respective banks. The Company is not responsible for the collection of receivables subject to these facilities, or for any legal proceedings and costs thereof in collecting these receivables. In case any commercial dispute between the Company and customers or other reasons results in the Company’s failure to perform the obligation under these facilities, the banks have requested the Company to issue promissory notes in the amounts equal to 10 percent of respective facilities or to transfer receivables in the amounts equal to 10 percent of respective facilities. Other than such arrangements, no collaterals were provided by the Company.

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Inventory	December 31, 2018 2019 (in thousands) Finished goods $ 9,406,248 9,005,001 Work-in-progress 11,133,846 9,537,700 Raw materials 5,769,010 4,917,371 $ 26,309,104 23,460,072

Investments in Equity-account_2

Investments in Equity-accounted Investees (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Interests in Other Entities	December 31, 2018 2019 (in thousands) Associates $ 5,973,127 5,820,759 Joint ventures 312,738 178,720 $ 6,285,865 5,999,479
Schedule of Interests in Associates	(a) Associates Principal December 31, 2018 December 31, 2019 Name of associate Principal activities place of business Ownership interest Amount Ownership interest Amount % (in thousands) % (in thousands) Lextar Electronics Corp. (“Lextar”) Manufacturing and sales of Light Emitting Diode Taiwan ROC 27 $ 3,082,178 27 $ 2,909,521 Star Shining Energy Corporation Investment Taiwan ROC 33 1,002,874 33 1,015,512 Raydium Semiconductor Corporation (“Raydium”) IC design Taiwan ROC 18 716,381 17 740,504 Daxin Materials Corp. (“Daxin”) Research, manufacturing, and sales of display related chemicals Taiwan ROC 25 654,940 25 688,813 Star River Energy Corp. (“SREC”) Investment Taiwan ROC 34 434,421 34 444,550 Others 82,333 21,859 $ 5,973,127 $ 5,820,759 None of the above associates is considered individually material to the Company. The following table summarized the amount recognized by the Company at its share of those associates. For the years ended December 31, 2017 2018 2019 (in thousands) The Company’s share of profits of associates $ 251,699 307,992 195,865 The Company’s share of other comprehensive loss of associates (62,084 ) (15,477 ) (35,224 ) The Company’s share of total comprehensive income of associates $ 189,615 292,515 160,641
Schedule of Joint Ventures	The following table summarized the amount recognized by the Company at its share of those joint ventures. For the years ended December 31, 2017 2018 2019 (in thousands) The Company’s share of profits (loss) of joint ventures $ (12,693 ) 3,722 (45,958 ) The Company’s share of other comprehensive income of joint ventures - - - The Company’s share of total comprehensive income (loss) of joint ventures $ (12,693 ) 3,722 (45,958 )

Acquisition of Subsidiaries (Ta

Acquisition of Subsidiaries (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Disclosure of Detailed Information About Business Combinations	(a) Consideration transferred Amounts (in thousands) Cash $ 467,920 Contingent consideration 283,354 $ 751,274 (b) Identifiable assets acquired and liabilities assumed The following table summarized the fair value of identifiable assets acquired and liabilities assumed recognized at the acquisition date: Fair value (in thousands) Cash $ 19,432 Accounts receivable and other current assets 36,851 Property, plant and equipment 3,712 Intangible assets 150,436 Accounts payable and other current liabilities (57,361 ) Other liabilities (2,120 ) $ 150,950 (c) Goodwill arising from the acquisition for which is attributable mainly to the synergies expected to be achieved from integrating ComQi into the Company’s existing business has been recognized as follows: Amounts (in thousands) Consideration transferred $ 751,274 Less: Fair value of identifiable net assets (150,950 ) $ 600,324

Disposal of Part of Ownership_2

Disposal of Part of Ownership Interest in Subsidiary without Losing Control (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Disclosure Of Effects Of Changes In Parents Ownership Interest In Subsidiary That Do Not Result In Loss Of Control On Equity Attributable To Owners Of Parent Explanatory	In November 2017, the Company disposed its ownership interest in DPTW totaling of 9.99% with consideration (net of costs of disposal) amounting to $1,776,984 thousand in cash. The effect of changes in ownership interest of the subsidiary which was attributable to owners of the parent was summarized as follows: For the year ended December 31, 2017 (in thousands) Consideration received $ 1,776,984 Carrying amount of the equity interest disposed of (1,190,529 ) Capital surplus – changes in ownership interest of subsidiary (12,099 ) Other equity – effect from foreign currency translation differences arising from foreign operations (56,160 ) Capital surplus – differences between consideration and carrying amount arising from disposal of interest in subsidiary $ 518,196

Disposal of Subsidiaries (Table

Disposal of Subsidiaries (Tables)	12 Months Ended
	Dec. 31, 2019
FGPC and TGPC to SSEC [Member]
Statement [LineItems]
Disclosure of Detailed Information About Carrying Value of Assets and Liabilities in Subsidiary or Businesses Acquired or Disposed	The carrying amounts of the assets and liabilities of the subsidiaries disposed of by the Company were as follows: Amounts (in thousands) Cash and cash equivalents $ 203,607 Accounts receivable and other receivables 4,513 Other current assets 38,649 Property, plant and equipment 260,828 Other assets 54,397 Payable for equipment (71,076 ) Accrued expense and other current liabilities (3,062 ) Long-term borrowings (84,187 ) Net assets disposed of $ 403,669
CGPC To SSEC [Member]
Statement [LineItems]
Disclosure of Detailed Information About Carrying Value of Assets and Liabilities in Subsidiary or Businesses Acquired or Disposed	The carrying amounts of the assets and liabilities of the subsidiary disposed of by the Company were as follows: Amounts (in thousands) Cash and cash equivalents $ 70,516 Other current assets 48,148 Payable for equipment (19,933 ) Net assets disposed of $ 98,731

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Property, Plant and Equipment	For the year ended December 31, 2018 Balance, Beginning of Year Additions Disposal or write off Reclassification, effect of change in exchange rate and others Balance, (in thousands) Cost: Land $ 9,008,659 - (161,728 ) 12,392 8,859,323 Buildings 124,010,869 53,706 (5,271,527 ) 2,426,312 121,219,360 Machinery and equipment 800,164,310 2,145,769 (13,164,282 ) 46,787,823 835,933,620 Other equipment 29,359,148 5,077,326 (1,775,217 ) 2,467,867 35,129,124 962,542,986 7,276,801 (20,372,754 ) 51,694,394 1,001,141,427 Accumulated depreciation and impairment loss: Buildings 33,825,375 3,097,807 (1,754,678 ) 862,822 36,031,326 Machinery and equipment 707,334,411 25,620,993 (12,828,449 ) 1,706,393 721,833,348 Other equipment 23,717,580 5,367,124 (1,775,840 ) 782,123 28,090,987 764,877,366 34,085,924 (16,358,967 ) 3,351,338 785,955,661 Prepayments for purchase of land and equipment, and construction in progress 27,267,469 26,228,260 - (47,095,020 ) 6,400,709 Net carrying amounts $ 224,933,089 221,586,475 For the year ended December 31, 2019 Balance, Beginning of Year Adjustments on initial application of new standards Additions Disposal or write off Reclassification, effect of change in exchange rate and others Balance, (in thousands) Cost: Land $ 8,859,323 - - - (675 ) 8,858,648 Buildings 121,219,360 - 325,184 (9,075 ) (1,838,220 ) 119,697,249 Machinery and equipment 835,933,620 - 1,320,958 (9,123,165 ) 13,450,424 841,581,837 Other equipment 35,129,124 (2,620 ) 4,910,462 (5,764,497 ) 1,561,968 35,834,437 1,001,141,427 (2,620 ) 6,556,604 (14,896,737 ) 13,173,497 1,005,972,171 Accumulated depreciation and impairment loss: Buildings 36,031,326 - 4,195,265 (9,021 ) (1,046,822 ) 39,170,748 Machinery and equipment 721,833,348 - 27,348,497 (9,080,856 ) (2,808,161 ) 737,292,828 Other equipment 28,090,987 (855 ) 5,575,376 (5,747,362 ) (271,736 ) 27,646,410 785,955,661 (855 ) 37,119,138 (14,837,239 ) (4,126,719 ) 804,109,986 Prepayments for purchase of land and equipment, and construction in progress 6,400,709 - 18,469,787 (4,837 ) (19,993,301 ) 4,872,358 Net carrying amounts $ 221,586,475 206,734,543
Summarized Capitalized Borrowing Costs and Interest Rate	The following table summarized the Company’s capitalized borrowing costs and the interest rate range applied for the capitalization: For the years ended December 31, 2017 2018 2019 (in thousands) Capitalized borrowing costs $ 624,235 421,618 141,966 Interest rate range 1.09%~ 1.04%~ 1.07%~ 5.71%

Lease Arrangements (Tables)

Lease Arrangements (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Quantitative Information Right Of Use Assets	(1) Right-of-use assets December 31, (in thousands) Carrying amount of right-of-use assets Land $ 11,595,815 Buildings 575,724 Other equipment 36,229 $ 12,207,768 For the year (in thousands) Additions to right-of-use assets $ 192,655 Depreciation charge for right-of-use assets Land $ 566,982 Buildings 238,969 Other equipment 66,590 $ 872,541
Schedule of Quantitative Information Lease liabilities	(2) Lease liabilities December 31, 2019 Future minimum lease payments Interests Present value of minimum lease payments (in thousands) Less than one year $ 879,518 197,151 682,367 Between one and five years 2,874,682 678,576 2,196,106 More than five years 9,588,087 1,375,483 8,212,604 $ 13,342,287 2,251,210 11,091,077 Lease liabilities － $ 682,367 Lease liabilities － $ 10,408,710
Schedule of Additional Information about Lease	The amounts recognized in profit or loss during the lease term were as follows: For the year (in thousands) Expenses relating to short-term leases $ 15,832 Expenses relating to leases of low-value assets, excluding short-term leases of low-value assets $ 315
Schedule of Maturity Analysis of Discounted Operating Lease Receivable	The maturity analysis of undiscounted operating lease receivable for the abovementioned assets are as follows: December 31, 2019 (in thousands) Year 1 $ 110,905 Year 2 110,316 Year 3 110,025 Year 4 106,272 Year 5 105,721 Year 6 onwards 2,079,849 Total undiscounted operating lease receivable $ 2,623,088

Investment Property (Tables)

Investment Property (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Investment Property	For the year ended December 31, 2018 Balance, Beginning Additions Reclassification and effect of change in exchange rate Balance, (in thousands) Land $ 717,823 - 12,483 730,306 Fair Value $ 2,213,184 2,252,170 For the year ended December 31, 2019 Balance, Beginning Additions Reclassification and effect of change in exchange rate Balance, (in thousands) Cost: Land $ 730,306 - (667 ) 729,639 Buildings - - 1,418,652 1,418,652 Right-of-use assets - - 28,570 28,570 730,306 - 1,446,555 2,176,861 Accumulated Depreciation: Buildings - 7,363 612,618 619,981 Right-of-use assets - 302 1,448 1,750 - 7,665 614,066 621,731 Net carrying amounts $ 730,306 1,555,130 Fair Value $ 2,252,170 4,057,848
Schedule of Fair Value Measurements Inputs	The significant inputs used in the fair value measurement were as follows: December 31, 2018 2019 Overall capital interest rate 1.86 % 2.53 % Rate of return 10.00 % 15.00 % Capitalization rate 12.00 % 8.00%~12.00 %

Intangible Assets (Tables)

Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Intangible Assets	For the year ended December 31, 2018 Balance, Beginning Additions Effect of change in consolidated entities Effect of change in exchange rate Balance, End of Year (in thousands) Cost: Goodwill $ - - 600,324 - 600,324 Patent and technology fee 12,275,548 - - (3,806 ) 12,271,742 Others - - 150,436 - 150,436 12,275,548 - 750,760 (3,806 ) 13,022,502 Accumulated amortization: Patent and technology fee 10,385,251 518,404 - (386 ) 10,903,269 Others - 22,565 - - 22,565 10,385,251 540,969 - (386 ) 10,925,834 Net carrying amounts $ 1,890,297 2,096,668 For the year ended December 31, 2019 Balance, Beginning Additions Effect of change in exchange rate Balance, End of Year (in thousands) Cost: Goodwill $ 600,324 - - 600,324 Patent and technology fee 12,271,742 1,711 (7,140 ) 12,266,313 Others 150,436 - - 150,436 13,022,502 1,711 (7,140 ) 13,017,073 Accumulated amortization: Patent and technology fee 10,903,269 436,815 (1,178 ) 11,338,906 Others 22,565 127,871 - 150,436 10,925,834 564,686 (1,178 ) 11,489,342 Net carrying amounts $ 2,096,668 1,527,731
Disclosure of Goodwill	The Company acquired goodwill and other intangible assets arising from the business combination in March 2018. Please refer to note 15 for the relevant information. For the purpose of impairment test, the following table shows the information of the operating business that the Company’s goodwill allocating to. December 31, 2018 2019 (in thousands) Display business $ 600,324 600,324

Other Current Assets and Othe_2

Other Current Assets and Other Noncurrent Assets (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Other Assets	December 31, 2018 2019 (in thousands) Refundable and overpaid tax $ 1,351,646 1,458,170 Refundable deposits 716,097 663,911 Prepayment for equipment 650,727 453,300 Prepayments for purchases 230,793 158,521 Long-term receivables 930,001 5,812 Long-term prepaid rents 1,364,111 - Others 2,869,869 2,961,194 8,113,244 5,700,908 Less: current (2,941,598 ) (3,295,562 ) Noncurrent $ 5,171,646 2,405,346

Short-term Borrowings (Tables)

Short-term Borrowings (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Short Term Borrowings	December 31, 2018 2019 (in thousands) Unsecured borrowings $ 546,472 1,725,602 Unused credit facilities $ 43,533,037 37,982,721 Interest rate range 2.54%~ 1.20%~

Long-term Borrowings (Tables)

Long-term Borrowings (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Long-term Borrowings	Bank or agent bank Durations December 31, 2018 December 31, 2019 (in thousands) Syndicated loans: Bank of Taiwan and others From Feb. 2019 to Feb. 2024 $ - 42,000,000 Bank of Taiwan and others From Mar. 2019 to Apr. 2023 - 23,000,000 Bank of Taiwan and others From May 2017 to May 2022 10,000,000 10,000,000 Bank of Taiwan and others From Apr. 2016 to Apr. 2019 36,175,000 - Bank of Taiwan and others From Feb. 2015 to Feb. 2019 5,912,000 - Bank of Taiwan and others From Jul. 2018 to Oct. 2019 210,000 - First Commercial Bank and others From Feb. 2016 to Jan. 2019 1,775,236 - Bank of China and others From Nov. 2015 to Nov. 2023 27,743,519 21,500,826 Unsecured loans From Apr. 2017 to Aug. 2023 2,976,158 8,050,310 Secured loans From Apr. 2017 to Apr. 2032 1,990,175 7,671,932 86,782,088 112,223,068 Less: transaction costs (476,770 ) (254,676 ) 86,305,318 111,968,392 Less: current portion (29,595,931 ) (9,535,198 ) $ 56,709,387 102,433,194 Unused credit facilities $ 79,933,812 32,265,575 Interest rate range 1.07%~ 1.00%~

Provisions (Tables)

Provisions (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Provisions	Warranties (i) Litigation and claims Others Total (in thousands) Balance at January 1, 2018 $ 1,546,960 89,520 249,483 1,885,963 Additions 276,846 336,061 571,113 1,184,020 Usage (259,109 ) - (187,842 ) (446,951 ) Reversals (100,754 ) - (215 ) (100,969 ) Effect of change in exchange rate (74 ) 5,647 10,413 15,986 Balance at December 31, 2018 1,463,869 431,228 642,952 2,538,049 Less: current (686,424 ) (431,228 ) (389,912 ) (1,507,564 ) Noncurrent $ 777,445 - 253,040 1,030,485 Balance at January 1, 2019 $ 1,463,869 431,228 642,952 2,538,049 Additions 554,935 - 11,800 566,735 Usage (422,976 ) (156,521 ) (63,661 ) (643,158 ) Reversals (303,423 ) (116,094 ) (264,008 ) (683,525 ) Effect of change in exchange rate (159 ) (6,312 ) (10,072 ) (16,543 ) Balance at December 31, 2019 1,292,246 152,301 317,011 1,761,558 Less: current (486,517 ) (152,301 ) (69,450 ) (708,268 ) Noncurrent $ 805,729 - 247,561 1,053,290 (i) The provisions for warranties were estimated based on historical experience of warranty claims rate associated with similar products and services. The Company expects most warranty claims will be made within two years from the date of the sale of the product.

Operating Leases (Tables)

Operating Leases (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Future Maturities of Operating Lease Payments	Future minimum lease payments under non-cancellable operating leases as of December 31, 2018 was as follows: December 31, 2018 (in thousands) Less than one year $ 927,351 Between one and five years 2,928,983 More than five years 2,085,877 $ 5,942,211
Schedule of Future Maturities of Operating Lease Receivable	Future minimum lease receivables under non-cancellable operating leases as of December 31, 2018 was as follows: December 31, 2018 (in thousands) Less than one year $ 105,788 Between one and five years 423,150 More than five years 2,188,728 $ 2,717,666

Employee Benefits (Tables)

Employee Benefits (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Net Defined Benefit Liability	(1) Reconciliation for AUO’s and M.Setek’s present value of defined benefit obligation and the fair value of plan assets December 31, 2018 2019 (in thousands) Present value of defined benefit obligation $ (3,257,962 ) (3,155,988 ) Fair value of plan assets 2,367,273 2,542,831 Net defined benefit liability $ (890,689 ) (613,157 )
Schedule of Reconciliation for Net Defined Benefit Liability and Its Components	(2) Movement in net defined benefit asset (liability) Defined benefit obligation Fair value of plan assets Net defined benefit asset (liability) 2018 2019 2018 2019 2018 2019 (in thousands) Balance at January 1, $ (3,128,927 ) (3,257,962 ) 2,213,018 2,367,273 (915,909 ) (890,689 ) Included in profit or loss Service cost (5,289 ) (4,104 ) - - (5,289 ) (4,104 ) Interest cost (49,598 ) (39,337 ) - - (49,598 ) (39,337 ) Expected return on plan assets - - 35,408 28,880 35,408 28,880 (54,887 ) (43,441 ) 35,408 28,880 (19,479 ) (14,561 ) Included in other comprehensive income Remeasurements (loss) gain: Actuarial (loss) gain arising from: - demographic assumptions (15,795 ) 89,851 - - (15,795 ) 89,851 - financial assumptions (178,212 ) (206,995 ) - - (178,212 ) (206,995 ) - experience adjustment 84,437 228,466 - - 84,437 228,466 Return on plan assets excluding interest income - - 52,614 76,788 52,614 76,788 (109,570 ) 111,322 52,614 76,788 (56,956 ) 188,110 Other Contributions paid by the employer - - 102,831 101,019 102,831 101,019 Benefits paid 36,915 33,936 (36,598 ) (31,129 ) 317 2,807 Effect of changes in exchange rates and others (1,493 ) 157 - - (1,493 ) 157 35,422 34,093 66,233 69,890 101,655 103,983 Balance at December 31, $ (3,257,962 ) (3,155,988 ) 2,367,273 2,542,831 (890,689 ) (613,157 )
Schedule of Principal Actuarial Assumptions Used	(i) Principal actuarial assumptions December 31, 2018 2019 Discount rate 0.21%~1.22% 0.18%~0.88% Rate of increase in future salary 0.77%~4.49% 0.77%~4.49%
Disclosure of Additional Information About Defined Benefit Plans	Reasonably possible changes at December 31, 2018 and 2019 to one of the relevant actuarial assumptions, holding other assumptions constant, would have affected the defined benefit obligation by the amounts shown below. December 31, 2018 December 31, 2019 Changes in assumptions Changes in assumptions + 0.25% - 0.25% + 0.25% - 0.25% (in thousands) (in thousands) Discount rate $ (160,307 ) 169,544 (150,970 ) 159,425 Rate of increase in future salary $ 166,250 (158,100 ) 156,774 (148,385 )

Capital and Other Components _2

Capital and Other Components of Equity (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Reserves Within Equity	The components of capital surplus as of December 31, 2018 and 2019 were as follows: December 31, 2018 2019 (in thousands) From common stock $ 52,756,091 52,756,091 From convertible bonds 6,049,862 6,049,862 From others 1,814,271 1,737,730 $ 60,620,224 60,543,683
Disclosure of Appropriation of Earnings	AUO’s appropriations of earnings for 2017 had been approved in the shareholders’ meeting held on June 15, 2018. The appropriations and dividends per share were as follows: For fiscal year 2017 Appropriation of earnings Dividends per share (in thousands, except for per share data) Legal reserve $ 3,235,942 Cash dividends to shareholders 14,436,368 $ 1.50 $ 17,672,310 The aforementioned appropriation of earnings for 2017 was consistent with the resolutions of the board of directors’ meeting held on March 23, 2018. AUO’s appropriations of earnings for 2018 had been approved in the shareholders’ meeting held on June 14, 2019. The appropriations and dividends per share were as follows: For fiscal year 2018 Appropriation of earnings Dividends per share (in thousands, except for per share data) Legal reserve $ 1,016,060 Special reserve 847,770 Cash dividends to shareholders 4,812,122 $ 0.50 $ 6,675,952 The aforementioned appropriation of earnings for 2018 was consistent with the resolutions of the board of directors’ meeting held on March 22, 2019.
Related Information On Treasury Share Transactions	The related information on treasury share transactions was as follows: Year Ended December 31, 2019 Reason for Number of shares, Beginning of Year Additions Reductions Number of shares, (in thousands of shares) Transferring to employees - 125,000 - 125,000
Schedule of Other Components of Equity	Cumulative translation differences Unrealized gains (losses) on available-for-sale financial Unrealized gains (losses) on cash flow hedges Total (in thousands) Balance at January 1, 2017 $ 531,006 224,299 21,992 777,297 Foreign operations – foreign currency translation differences (1,882,545 ) - - (1,882,545 ) Effective portion of changes in fair value of cash flow hedges - - (21,992 ) (21,992 ) Net change in fair value of available-for-sale financial assets - 1,146,422 - 1,146,422 Equity-accounted investees – share of other comprehensive income (68,637 ) 6,310 - (62,327 ) Related tax 299,207 - - 299,207 Balance at December 31, 2017 $ (1,120,969 ) 1,377,031 - 256,062 Cumulative translation differences Unrealized gains (losses) on financial Unrealized gains (losses) on available-for-sale financial Total (in thousands) Balance at January 1, 2018 $ (1,120,969 ) - 1,377,031 256,062 Adjustments on initial application of new standards - 1,303,816 (1,377,031 ) (73,215 ) Foreign operations – foreign currency translation differences (336,902 ) - - (336,902 ) Net change in fair value of financial assets at FVTOCI - (754,813 ) - (754,813 ) Equity-accounted investees – share of other comprehensive income (19,716 ) 3,053 - (16,663 ) Realized gain on sales of securities reclassified to profit or loss (107,457 ) - - (107,457 ) Cumulative unrealized loss of equity instruments transferred to retained earnings due to disposal - 50,084 - 50,084 Group reorganization (22,225 ) - - (22,225 ) Related tax 157,359 - - 157,359 Balance at December 31, 2018 $ (1,449,910 ) 602,140 - (847,770 ) Cumulative translation differences Unrealized gains (losses) on financial Total (in thousands) Balance at January 1, 2019 $ (1,449,910 ) 602,140 (847,770 ) Foreign operations – foreign currency translation differences (2,043,931 ) - (2,043,931 ) Net change in fair value of financial assets at FVTOCI - 519,100 519,100 Equity-accounted investees – share of other comprehensive income (38,512 ) 3,358 (35,154 ) Realized gain on sales of securities reclassified to profit or loss (9,098 ) - (9,098 ) Related tax 411,469 - 411,469 Balance at December 31, 2019 $ (3,129,982 ) 1,124,598 (2,005,384 )
Schedule of NonControlling Interests	For the years ended December 31, 2017 2018 2019 (in thousands) Balance at the beginning of the year $ 18,388,204 17,068,501 14,416,559 Equity attributable to non-controlling interests: 　Loss for the year (2,120,737 ) (2,177,869 ) (2,413,718 ) 　Adjustment of changes in ownership of investees (6,421 ) (20,998 ) 110,028 　Foreign currency translation differences (355,700 ) (306,963 ) (404,575 ) 　Unrealized losses on financial assets at FVTOCI - (1,474 ) - 　Remeasurement of defined benefit plans 201 - - 　Effect of disposal of interest in subsidiary to non-controlling interests 1,258,788 - - 　Effect of acquisition of non-controlling interests - - (389,430 ) 　Proceeds from subsidiaries capital increase and others (95,834 ) (144,638 ) (13,957 ) Balance at the end of the year $ 17,068,501 14,416,559 11,304,907

Share-based Payments (Tables)

Share-based Payments (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Number and Weighted Average Exercise Prices of DPTW Option Plan	Information about DPTW’s outstanding stock options is as follows: For the year ended Weighted-average exercise price Number of options (shares) Outstanding at January 1 $ 19.04 2,913,000 Options expired - (2,913,000 ) Outstanding at December 31 - - Exercisable at December 31 -
Schedule of Terms and Conditions of ACTW Option Plan	(1) The key terms and conditions related to the grants under ACTW’s outstanding employee stock option plan were disclosed as follows: Grant date Total number of options issued (units in thousands) Contractual life of options Exercisable period Exercise price 2014 Employee stock option plan Sep. 1, 2014 20 Sep.1, 2014 – Aug. 31, 2019 After Aug. 31, 2016 $10
Schedule of Valuation Information of ACTW Option Plan	The fair value of the employee stock options granted by ACTW was measured at the dates of grant using the Binomial option pricing model. The valuation information was as follows: 2014 Employee Stock Option Plan Expected volatility 38.88% Risk-free interest rate 1.1648% Expected duration 5 years Fair value at the grant date NT$0.20/per share
Schedule of Number and Weighted Average Exercise Prices of ACTW Option Plan	(4) Information about ACTW’s outstanding stock options is as follows: For the years ended December 31, 2018 2019 Weighted-average exercise price Number of options (shares) Weighted-average exercise price Number of options (shares) Outstanding at January 1 $ 10 16,601,000 $ 10 13,291,000 Options exercised 10 (2,260,000 ) 10 (11,995,000 ) Options expired - (1,050,000 ) - (1,296,000 ) Outstanding at December 31 10 13,291,000 - - Exercisable at December 31 13,291,000 -

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Revenue from Contracts with Customers on Primary Geographical Markets	For the year ended December 31, 2018 Display segment Energy segment Total segments (in thousands) Primary geographical markets: PRC $ 112,542,529 1,089,508 113,632,037 Taiwan 93,126,115 6,231,767 99,357,882 Singapore 39,363,415 7,515 39,370,930 Japan 19,748,373 1,418,491 21,166,864 Others 26,004,322 8,102,354 34,106,676 $ 290,784,754 16,849,635 307,634,389 For the year ended December 31, 2019 Display segment Energy segment Total segments (in thousands) Primary geographical markets: PRC $ 97,084,436 1,277,799 98,362,235 Taiwan 78,394,325 4,835,269 83,229,594 Singapore 38,526,625 7,666 38,534,291 Japan 19,877,671 1,046,332 20,924,003 Others 22,784,165 4,957,406 27,741,571 $ 256,667,222 12,124,472 268,791,694
Schedule of Revenue from Contracts on Major Customers	For the year ended December 31, 2018 Display segment Energy segment Total segments (in thousands) Major products: Products for Televisions $ 113,194,567 - 113,194,567 Products for Mobile PCs and Devices 74,375,305 - 74,375,305 Products for Monitors 47,024,353 - 47,024,353 Products for Commercial and Others (i) 56,190,529 - 56,190,529 Solar Products - 16,849,635 16,849,635 $ 290,784,754 16,849,635 307,634,389 For the year ended December 31, 2019 Display segment Energy segment Total segments (in thousands) Major products: Products for Televisions $ 87,269,763 - 87,269,763 Products for Mobile PCs and Devices 69,305,510 - 69,305,510 Products for Monitors 39,522,268 - 39,522,268 Products for Commercial and Others (i) 60,569,681 - 60,569,681 Solar Products - 12,124,472 12,124,472 $ 256,667,222 12,124,472 268,791,694
Schedule of Revenue from Contracts on Major Customers	For the year ended December 31, 2018 Display segment Energy segment Total segments (in thousands) Major customers: Customer A $ 35,358,013 - 35,358,013 Others (individually not greater than 10%) 255,426,741 16,849,635 272,276,376 $ 290,784,754 16,849,635 307,634,389 For the year ended December 31, 2019 Display segment Energy segment Total segments (in thousands) Major customers: Customer A $ 33,142,985 - 33,142,985 Others (individually not greater than 10%) 223,524,237 12,124,472 235,648,709 $ 256,667,222 12,124,472 268,791,694 (i) Others include sales from products for other applications and sales of raw materials, components and from service charges.

Revenue (Tables)

Revenue (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Revenues	For the year ended December 31, 2017 (in thousands) Sale of goods $ 329,584,136 Other operating revenue 11,444,131 $ 341,028,267

The Nature of Expenses (Tables)

The Nature of Expenses (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Depreciation of Property, Plant and Equipment	(a) Depreciation of property, plant and equipment For the years ended December 31, 2017 2018 2019 (in thousands) Recognized in cost of sales $ 31,660,279 29,980,415 31,599,910 Recognized in operating expenses (i) 4,140,951 3,706,146 4,093,123 $ 35,801,230 33,686,561 35,693,033
Schedule of Amortization of Intangible Assets	(b) Amortization of intangible assets For the years ended December 31, 2017 2018 2019 (in thousands) Recognized in cost of sales $ 628,606 518,403 436,815 Recognized in operating expenses (i) - 22,566 127,871 $ 628,606 540,969 564,686
Schedule of Employee Benefits Expenses	(c) Employee benefits expenses For the years ended December 31, 2017 2018 2019 (in thousands) Salaries and wages $ 37,818,321 34,933,925 30,824,887 Labor and health insurances 1,967,688 2,009,652 1,917,244 Retirement benefits 1,917,136 1,967,557 1,776,638 Other employee benefits 3,197,324 3,839,988 3,635,371 $ 44,900,469 42,751,122 38,154,140 Employee benefits expense summarized by function Recognized in cost of sales $ 34,703,579 33,455,273 29,453,257 Recognized in operating expenses (i) 10,196,890 9,295,849 8,700,883 $ 44,900,469 42,751,122 38,154,140 (i) Operating expenses are inclusive of selling and distribution expenses, general and administrative expenses and research and development expenses.

Other Income (Tables)

Other Income (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Other Income	For the years ended December 31, 2017 2018 2019 (in thousands) Interest income on bank deposits $ 591,995 832,621 879,053 Interest income on government bonds with reverse repurchase agreements and others 20,215 8,994 6,467 Rental income, net 531,442 628,401 488,811 Dividend income 248,514 468,263 295,575 Grants 1,801,585 2,716,197 2,734,987 Others 636,146 757,649 915,378 $ 3,829,897 5,412,125 5,320,271

Other Gains and Losses (Tables)

Other Gains and Losses (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Other Gains and Losses	For the years ended December 31, 2017 2018 2019 (in thousands) Foreign exchange gains (losses), net $ (1,364,929 ) (41,391 ) (168,499 ) Gains on valuation of financial instruments at FVTPL, net 1,646,034 507,532 381,620 Gains (losses) on disposals of investments and financial assets, net 42,788 - (13,154 ) Gains on disposals of property, plant and equipment, net 330,814 1,923,044 106,546 Impairment losses on assets (1,046,668 ) (399,363 ) (2,298,646 ) Gains (losses) from litigation and others (584,599 ) (501,770 ) 396,519 $ (976,560 ) 1,488,052 (1,595,614 )

Finance Costs (Tables)

Finance Costs (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Finance Costs	For the years ended December 31, 2017 2018 2019 (in thousands) Interest expense on bank borrowings $ 2,519,839 2,442,872 2,714,080 Interest expense on lease liabilities - - 209,607 Interest expense on others 348,022 220,733 327,683 $ 2,867,861 2,663,605 3,251,370

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Components of Income Tax Expense	(a) The components of income tax expense (benefit) for the years ended December 31, 2017, 2018 and 2019 were as follows: For the years ended December 31, 2017 2018 2019 (in thousands) Current income tax expense (benefit): Current year $ 3,719,483 1,444,698 752,863 Adjustment to prior years and others 246,264 (1,772,898 ) (684,197 ) 3,965,747 (328,200 ) 68,666 Deferred tax expense (benefit): Temporary differences (1,271,415 ) (632,785 ) 584,559 Investment tax credit and tax losses carryforwards (3,819,489 ) 1,998,662 682,930 Effect of changes in statutory income tax rate - (715,303 ) - (5,090,904 ) 650,574 1,267,489 Total income tax expense (benefit) $ (1,125,157 ) 322,374 1,336,155
Schedule of information About Income Taxes Expense Benefit Recognized Directly in Other Comprehensive Income	(b) Income taxes expense (benefit) recognized directly in other comprehensive income for the years ended December 31, 2017, 2018 and 2019 were as follows: For the years ended December 31, 2017 2018 2019 (in thousands) Items that will never be reclassified to profit or loss: Remeasurement of defined benefit obligations $ (155,930 ) (38,908 ) 37,622 Items that are or may be reclassified subsequently to profit or loss: Foreign operations – foreign currency translation differences $ (316,372 ) (191,809 ) (459,729 )
Schedule of Income Tax Reconciliation	(c) Reconciliation of the expected income tax expense (benefit) calculated based on the ROC statutory income tax rate compared with the actual income tax expense (benefit) as reported in the consolidated statements of comprehensive income for the years ended December 31, 2017, 2018 and 2019, was as follows: For the years ended December 31 2017 2018 2019 (in thousands) Profit (Loss) before income taxes $ 39,363,606 11,216,151 (19,844,754 ) Income tax expense at AUO’s statutory tax rate 6,691,813 2,243,230 (3,968,951 ) Effect of different subsidiaries income tax rate 348,192 (484,055 ) 38,756 Share of profit (loss) of equity-accounted subsidiaries (708,417 ) 795,459 (73,968 ) Effect of changes in statutory income tax rate - (715,303 ) - Effect of change of unrecognized deductible temporary differences, tax losses carryforwards, and investment tax credits (10,645,339 ) 138,969 5,947,778 Net of non-taxable income and non-deductible expense 698,540 (186,957 ) 265,119 Tax on undistributed earnings, net 2,987,763 323,559 7,709 Adjustments to prior year (528,662 ) (1,772,898 ) (684,197 ) Others 30,953 (19,630 ) (196,091 ) Income tax expense (benefit) $ (1,125,157 ) 322,374 1,336,155 Effective tax rate (2.85 )% 2.87 % (6.73 )%
Schedule of Deferred Taxes	(d) The components of deferred tax assets and liabilities were as follows: Deferred tax assets Deferred tax liabilities Total December 31, 2018 December 31, 2019 December 31, 2018 December 31, 2019 December 31, 2018 December 31, 2019 (in thousands) Investment tax credits $ 542,115 385,728 - - 542,115 385,728 Tax losses carryforwards 2,760,163 2,223,440 - - 2,760,163 2,223,440 Unrealized loss and expenses 310,192 166,393 (5,556 ) (5,321 ) 304,636 161,072 Inventories write-down 1,027,680 879,267 - - 1,027,680 879,267 Foreign investment gains under the equity method - - (1,049,091 ) (1,043,486 ) (1,049,091 ) (1,043,486 ) Remeasurement of defined benefit plans 194,838 157,216 - - 194,838 157,216 Foreign operations – foreign currency translation differences 426,333 886,062 - - 426,333 886,062 Others 1,371,347 483,511 (577,517 ) (1,864 ) 793,830 481,647 Deferred tax assets (liabilities) $ 6,632,668 5,181,617 (1,632,164 ) (1,050,671 ) 5,000,504 4,130,946
Schedule of Changes in Deferred Tax Assets and Liabilities	(e) Changes in deferred tax assets and liabilities were as follows: January 1, 2018 Recognized Recognized Effect of change in consolidated entities, December Recognized Recognized Effect of change in consolidated entities, December (in thousands) Investment tax credits $ 656,480 (132,840 ) - 18,475 542,115 (148,453 ) - (7,934 ) 385,728 Tax losses carryforwards 3,942,012 (1,181,429 ) - (420 ) 2,760,163 (534,477 ) - (2,246 ) 2,223,440 Unrealized loss and expenses 222,739 81,893 - 4 304,636 (143,534 ) - (30 ) 161,072 Inventories write-down 644,887 386,558 - (3,765 ) 1,027,680 (148,035 ) - (378 ) 879,267 Foreign investment losses (gains) under the equity method (890,153 ) (158,938 ) - - (1,049,091 ) 5,605 - - (1,043,486 ) Remeasurement of defined benefit plans 155,930 - 38,908 - 194,838 - (37,622 ) - 157,216 Foreign operations – foreign currency translation differences 234,524 - 191,809 - 426,333 - 459,729 - 886,062 Others 464,368 354,182 - (24,720 ) 793,830 (298,595 ) - (13,588 ) 481,647 Total $ 5,430,787 (650,574 ) 230,717 (10,426 ) 5,000,504 (1,267,489 ) 422,107 (24,176 ) 4,130,946
Schedule of Unrecognized Deferred Tax Assets	(f) Unrecognized deferred tax assets and unrecognized deferred tax liabilities Deferred tax assets have not been recognized in respect of the following items. December 31, 2018 2019 (in thousands) Unused tax losses carryforwards $ 28,697,671 32,445,130 Unused investment tax credits 853,837 981,360 Difference in depreciation expense for tax and financial purposes 1,972,536 1,866,430 Inventories write-down 19,852 22,875 Others 646,390 1,730,739 $ 32,190,286 37,046,534
Schedule of Information About Unused Tax Losses Carryforwards	As of December 31, 2019, the expiration period for abovementioned unrecognized deferred tax assets of unused tax losses carryforwards were as follows: Year of assessment Unrecognized deferred tax assets Expiration in year (in thousands) 2011 $ 2,904,785 2020 ~ 2021 2012 11,042,933 2021 ~ 2022 2013 1,747,050 2022 ~ 2023 2014 2,347,376 2023 ~ 2024 2015 2,159,621 2020 ~ 2025 2016 4,259,267 2020 ~ 2026 2017 2,314,089 2021 ~ 2026 2018 1,279,958 2023 ~ 2028 2019 (estimated) 4,390,051 2023 ~ 2029 $ 32,445,130

Earnings (Loss) per Share (Tabl

Earnings (Loss) per Share (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Basic Earnings Per Share	(a) Basic earnings (loss) per share for the years ended December 31, 2017, 2018 and 2019 were calculated as follows: For the years ended December 31, 2017 2018 2019 (in thousands, except for per share data) Profit (loss) attributable to AUO’s shareholders $ 42,609,500 13,071,646 (18,767,191 ) Weighted-average number of common shares outstanding during the year (basic) 9,624,245 9,624,245 9,597,268 Basic earnings (loss) per share $ 4.43 1.36 (1.96 )
Schedule of Diluted Earnings Per Share	(b) Diluted earnings (loss) per share for the years ended December 31, 2017, 2018 and 2019 were calculated as follows: For the years ended December 31, 2017 2018 2019 (in thousands, except for per share data) Profit (loss) attributable to AUO’s shareholders $ 42,609,500 13,071,646 (18,767,191 ) Weighted-average number of common shares outstanding during the year (including the effect of dilutive potential common stock): Weighted-average number of common shares (basic) 9,624,245 9,624,245 9,597,268 Effect of employee remuneration in stock 347,903 164,609 - Weighted-average number of common shares (diluted) 9,972,148 9,788,854 9,597,268 Diluted earnings (loss) per share $ 4.27 1.34 (1.96 )

Cash Flow Information (Tables)

Cash Flow Information (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Disclosure of Detailed Information About Reconciliation of Liabilities to Cash Flow Arising From Financing Activities	The reconciliation of liabilities to cash flows arising from financing activities was as follows: Long-term borrowings (including current installments) Short-term borrowings Guarantee deposits Total liabilities from financing activities (in thousands) Balance at January 1, 2017 $ 124,262,620 526,723 838,263 125,627,606 Cash flows (12,571,198 ) 2,903,927 (34,654 ) (9,701,925 ) Non-cash changes: Changes in exchange rate (1,142,980 ) (6,274 ) 34,873 (1,114,381 ) Effect of change in consolidated entities (84,187 ) - - (84,187 ) Amortization on transaction costs 143,755 - - 143,755 Balance at December 31, 2017 $ 110,608,010 3,424,376 838,482 114,870,868 Cash flows (24,464,961 ) (2,817,894 ) (13,402 ) (27,296,257 ) Non-cash changes: Changes in exchange rate 27,663 (60,010 ) (8,568 ) (40,915 ) Amortization on transaction costs 134,606 - - 134,606 Balance at December 31, 2018 $ 86,305,318 546,472 816,512 87,668,302 Long-term borrowings (including current installments) Short-term borrowings Guarantee deposits Lease liabilities Total liabilities from financing activities (in thousands) Balance at January 1, 2019 $ 86,305,318 546,472 816,512 12,689,526 100,357,828 Cash flows 26,501,234 1,188,250 (1,828 ) (694,922 ) 26,992,734 Non-cash changes: Increase (decrease) in lease liabilities - - - (872,224 ) (872,224 ) Changes in exchange rate (1,059,445 ) (9,120 ) (29,228 ) (31,303 ) (1,129,096 ) Amortization on transaction costs 221,285 - - - 221,285 Balance at December 31, 2019 $ 111,968,392 1,725,602 785,456 11,091,077 125,570,527

Financial Instruments (Tables)

Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Carrying Amount and Fair Value of Financial Instruments	Other than those, the carrying amount and fair value of other financial instruments of the Company as of December 31, 2018 and 2019 were as follows: December 31, 2018 December 31, 2019 Carrying Amount Fair Value Carrying Amount Fair Value (in thousands) Financial assets: Financial assets at FVTPL: Financial assets mandatorily measured at FVTPL $ 1,709,531 1,709,531 1,521,406 1,521,406 Financial assets at FVTOCI 6,979,925 6,979,925 7,545,171 7,545,171 Financial assets at amortized cost: Long-term receivables 930,001 930,001 5,812 5,812 Refundable deposits 716,097 716,097 663,911 663,911 Financial liabilities: Financial liabilities at FVTPL: Financial liabilities held for trading 22,115 22,115 18,859 18,859 Financial liabilities at amortized cost: Long-term borrowings (including current installments) 86,305,318 86,305,318 111,968,392 111,968,392 Guarantee deposits 816,512 816,512 785,456 785,456
Schedule of Fair Value Measurement of Assets and Liabilities on a Recurring Basis	Financial assets and liabilities measured at fair value on a recurring basis were as follows: Level 1 Level 2 Level 3 Total (in thousands) December 31, 2018 Financial assets at FVTPL: Financial assets mandatorily measured at FVTPL $ - 1,709,531 - 1,709,531 Financial assets at FVTOCI 6,803,900 - 176,025 6,979,925 Financial assets at amortized cost: Long-term receivables - 930,001 - 930,001 Financial liabilities at FVTPL: Financial liabilities held for trading - 22,115 - 22,115 December 31, 2019 Financial assets at FVTPL: Financial assets mandatorily measured at FVTPL $ - 1,521,406 - 1,521,406 Financial assets at FVTOCI 7,356,501 - 188,670 7,545,171 Financial assets at amortized cost: Long-term receivables - 5,812 - 5,812 Financial liabilities at FVTPL: Financial liabilities held for trading - 18,859 - 18,859
Schedule of Changes in Level 3 Fair Value Measurement	(4) Reconciliation for recurring fair value measurements categorized within Level 3 For the year ended December 31, 2017 (in thousands) Available-for-sale financial assets without quoted market prices Balance at the beginning of the year $ 193,582 Net realized/unrealized losses included in profit or loss (i) (30,000 ) Purchases 14,233 Balance at the end of the year $ 177,815 (i) Change in unrealized losses, which were included in profit or loss, relating to those available-for-sale assets without quoted market prices held at December 31, 2017 was $30,000 thousand. For the years ended December 31, 2018 2019 (in thousands) Financial assets at FVTOCI － Balance at the beginning of the year $ - 176,025 Adjustments on initial application of IFRS 9 177,815 - Net gains (losses) included in other comprehensive income 9,990 (33,501 ) Purchases 34,157 47,182 Disposals (45,937 ) - Effect of exchange rate change - (1,036 ) Balance at the end of the year $ 176,025 188,670
Schedule of Changes in Level 3 Valuation Processes and Quantitative Fair Value Measurement	(5) Description of valuation processes and quantitative disclosures for fair value measurements categorized within Level 3 Item Valuation technique Significant Inter-relationship between significant Financial assets at FVTOCI–equity instruments without active market Market approach Ÿ Price-Book ratio (0.99~5.2 at Dec. 31, 2018 and 0.7~2.95 at Dec. 31, 2019) Ÿ Price-Earnings ratio (14.69~112.13 at Dec. 31, 2018 and 7.85~31.28 at Dec. 31, 2019) Ÿ Discount for lack of marketability (20% at Dec. 31, 2018 and 20% ~28% at Dec. 31, 2019) Ÿ The higher the price-book ratio is, the higher the fair value is. Ÿ The higher the price-earnings ratio is, the higher the fair value is. Ÿ The greater degree of lack of marketability is, the lower the fair value is.

Financial Risk Management (Tabl

Financial Risk Management (Tables)	12 Months Ended
	Dec. 31, 2019
Disclosure Of Financial Risk Management [line items]
Schedule of maturity analysis for financial liabilities	The following, except for payables (including related parties) and equipment and construction payable, are the contractual maturities of other financial liabilities. The amounts include estimated interest payments (except for short-term borrowings) but exclude the impact of netting agreements. Contractual cash 2019.1.1~ 2020.1.1~ 2022.1.1~ 2024 and (in thousands) December 31, 2018 Non-derivative financial liabilities Short-term borrowings $ 546,472 546,472 - - - Long-term borrowings (including current installments) 92,485,536 31,854,500 45,935,987 14,395,139 299,910 Guarantee deposits 816,512 36,977 - - 779,535 Derivative financial instruments Foreign currency forward contracts － inflows (12,453,853 ) (12,453,853 ) - - - Foreign currency forward contracts － 12,436,885 12,436,885 - - - $ 93,831,552 32,420,981 45,935,987 14,395,139 1,079,445 Contractual cash 2020.1.1~ 2021.1.1~ 2023.1.1~ 2025 and (in thousands) December 31, 2019 Non-derivative financial liabilities Short-term borrowings $ 1,725,602 1,725,602 - - - Long-term borrowings (including current installments) 119,185,207 12,149,855 55,120,591 50,630,751 1,284,010 Guarantee deposits 785,456 23,510 11,187 - 750,759 Derivative financial instruments Foreign currency forward contracts － inflows (8,731,109 ) (8,731,109 ) - - - Foreign currency forward contracts － 8,727,770 8,727,770 - - - $ 121,692,926 13,895,628 55,131,778 50,630,751 2,034,769
Currency risk [member]
Disclosure Of Financial Risk Management [line items]
Disclosure of detailed information about exposure to foreign currency risk	The Company’s significant exposure to foreign currency risk was as follows: Foreign currency amounts Exchange NTD (in thousands) (in thousands) December 31, 2018 Financial assets Monetary items USD $ 2,092,501 30.8020 64,453,216 JPY 11,872,572 0.2775 3,294,639 EUR 29,681 35.2036 1,044,878 Foreign currency amounts Exchange NTD (in thousands) (in thousands) Non-monetary items USD $ 2,799 30.8020 86,215 RMB 20,258 4.4813 90,782 Financial liabilities Monetary items USD 1,188,175 30.8020 36,598,166 JPY 25,296,499 0.2775 7,019,778 EUR 209 35.2036 7,358 December 31, 2019 Financial assets Monetary items USD $ 1,499,405 30.1350 45,184,570 JPY 22,122,120 0.2768 6,123,403 EUR 46,595 33.7422 1,572,218 Non-monetary items USD 1,726 30.1350 52,013 RMB - 4.3155 - Financial liabilities Monetary items USD 1,515,582 30.1350 45,672,064 JPY 22,187,729 0.2768 6,141,563 EUR 239 33.7422 8,064
Schedule of sensitivity analysis of currency risk	Depreciation or appreciation of the NTD by 1% against the USD, EUR and JPY at December 31, 2018 and 2019, while all other variables were remained constant, would have increased or decreased the net profit before tax for the years ended December 31, 2018 and 2019 as follows: For the years ended December 31, 2018 2019 (in thousands) 1% of depreciation $ 251,674 10,585 1% of appreciation (251,674 ) (10,585 )

Capital Management (Tables)

Capital Management (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of information about capital management	The Company aims to enhance the returns of its shareholders through achieving an optimized debt-to-equity ratio from time to time. December 31, 2018 2019 (in thousands) Short-term borrowings $ 546,472 1,725,602 Long-term borrowings (including current installments) 86,305,318 111,968,392 Total liabilities 190,765,874 207,455,122 Total equity 207,785,306 178,901,874 Debt-to-equity ratio 92 % 116 % Net debt-to-equity ratio (1) 9 % 19 % (1) Net debt-to-equity ratio is defined as short-term borrowings plus long-term borrowings less cash and cash equivalents and divided by total equity.

Related-party Transactions (Tab

Related-party Transactions (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Disclosure of information about key management personnel	Key management personnel’s compensation comprised: For the years ended December 31, 2017 2018 2019 (in thousands) Short-term employee benefits $ 566,231 345,019 243,203 Post-employment benefits 2,244 2,547 2,633 $ 568,475 347,566 245,836
Schedule of sales transactions between related parties	(1) Sales Sales Accounts receivable For the years ended December 31, December 31, 2017 2018 2019 2018 2019 (in thousands) Associates $ 1,216,868 1,898,336 1,227,987 696,423 280,009 Others (i) 11,959,720 12,050,450 10,347,963 2,057,830 1,498,490 $ 13,176,588 13,948,786 11,575,950 2,754,253 1,778,499
Schedule of purchases transactions between related parties	(2) Purchases Purchases Accounts payable to related parties For the years ended December 31, December 31, 2017 2018 2019 2018 2019 (in thousands) Associates $ 8,667,555 9,185,563 8,664,439 3,664,742 2,825,292 Joint ventures 1,057,106 1,449,636 1,027,147 - 72,942 Others (i) 17,549,228 18,589,791 17,077,497 4,496,444 4,052,594 $ 27,273,889 29,224,990 26,769,083 8,161,186 6,950,828
Schedule of acquisition of property, plant and equipment in related party transactions	(3) Acquisition of property, plant and equipment For the years ended December 31, 2017 2018 2019 (in thousands) Associates $ 1,549 6,527 6,555 Others (i) 2,801 4,449 17,436 $ 4,350 10,976 23,991
Schedule of disposal of property, plant and equipment in related party transactions	(4) Disposal of property, plant and equipment and others Proceeds from disposal For the years ended December 31, 2017 2018 2019 (in thousands) Others (i) $ 3,352 - 835 Gains on disposal For the years ended December 31, 2017 2018 2019 (in thousands) Others (i) $ 2,212 - 72
Schedule of other related party transactions	(5) Other related party transactions Other receivables due from December 31, 2018 2019 (in thousands) Associates $ 8,161 2,727 Others (i) 4,784 1,229 $ 12,945 3,956 Other payables due to related parties (including payable for equipment) December 31, 2018 2019 (in thousands) Associates $ 18,148 13,980 Others (i) 10,027 35,991 $ 28,175 49,971 Rental income For the years ended December 31, 2017 2018 2019 (in thousands) Associates $ 48,223 55,044 52,227 Joint ventures 6,611 6,611 6,611 Others (i) 82,427 91,222 107,587 $ 137,261 152,877 166,425 Administration and other income For the years ended December 31, 2017 2018 2019 (in thousands) Associates $ 14,311 18,580 17,980 Joint ventures - 1,060 223 Others (i) 9,246 8,789 7,996 $ 23,557 28,429 26,199 Other expenses For the years ended December 31, 2017 2018 2019 (in thousands) Associates $ 28,017 37,155 20,157 Joint ventures 1,389 567 36 Others (i) 35,040 29,336 59,287 $ 64,446 67,058 79,480 (i) Entities which are substantive related parties of the Company but not been accounted for using the equity method, mainly Qisda Corporation and its subsidiaries.

Pledged Assets (Tables)

Pledged Assets (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Assets Pledged As Collateral	The carrying amounts of the assets which the Company pledged as collateral were as follows: December 31, Pledged assets Pledged to secure 2018 2019 (in thousands) Restricted cash in banks (i) Customs duties and guarantee for warranties $ 91,753 35,809 Land and building Long-term borrowings 27,696,480 28,423,642 Machinery and equipment Long-term borrowings 37,317,602 42,968,184 $ 65,105,835 71,427,635 (i) Classified as other current financial assets and other noncurrent assets by its liquidity.

Contingent Liabilities and Co_2

Contingent Liabilities and Commitments (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Outstanding Letters of Credit	As at December 31, 2019, the Company had the following outstanding letters of credit for the purpose of purchasing machinery and equipment and materials: Currency December 31, (in thousands) USD 5,768 JPY 1,951,409

Segment, Geographic and Reven_2

Segment, Geographic and Revenue Information (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Segment Reporting Information	The Company’s operating segment information for the years ended December 31, 2017, 2018 and 2019 was as follows: For the year ended December 31, 2017 Display segment Energy segment Total (in thousands) Net revenue from external customers $ 322,335,330 18,692,937 341,028,267 Depreciation and amortization $ 34,816,463 1,613,373 36,429,836 Inventory write-down $ 3,423,097 333,629 3,756,726 Segment profit (loss) (i) $ 39,971,375 (832,251 ) 39,139,124 Other income 3,829,897 Other gains and losses (976,560 ) Finance costs (2,867,861 ) Share of profit of equity-accounted investees 239,006 Consolidated profit before income tax $ 39,363,606 For the year ended December 31, 2018 Display segment Energy segment Total (in thousands) Net revenue from external customers $ 290,784,754 16,849,635 307,634,389 Depreciation and amortization $ 32,981,240 1,246,290 34,227,530 Inventory write-down $ 5,094,195 77,557 5,171,752 Segment profit (loss) (i) $ 7,792,505 (1,124,640 ) 6,667,865 Other income 5,412,125 Other gains and losses 1,488,052 Finance costs (2,663,605 ) Share of profit of equity-accounted investees 311,714 Consolidated profit before income tax $ 11,216,151 For the year ended December 31, 2019 Display segment Energy segment Total (in thousands) Net revenue from external customers $ 256,667,222 12,124,472 268,791,694 Depreciation and amortization $ 35,237,582 1,020,137 36,257,719 Inventory write-down $ 5,109,473 76,031 5,185,504 Segment profit (loss) (i) $ (19,484,401 ) (983,547 ) (20,467,948 ) Other income 5,320,271 Other gains and losses (1,595,614 ) Finance costs (3,251,370 ) Share of profit of equity-accounted investees 149,907 Consolidated loss before income tax $ (19,844,754 ) (i) There were no intersegment revenues or other transactions between operating segments for the years ended December 31, 2017, 2018 and 2019.
Schedule of Revenue and Non Current Assets By Geographical Areas	(1) Net revenue from external customers For the years ended December 31, 2017 2018 2019 Region (in thousands) PRC $ 125,341,648 113,632,037 98,362,235 Taiwan 108,288,387 99,357,882 83,229,594 Singapore 35,939,290 39,370,930 38,534,291 Japan 32,739,262 21,166,864 20,924,003 Others 38,719,680 34,106,676 27,741,571 $ 341,028,267 307,634,389 268,791,694 (2) Consolidated noncurrent assets (ii) December 31, 2018 2019 Region (in thousands) Taiwan $ 161,358,754 163,237,676 PRC 61,284,667 54,890,846 Others 6,941,674 6,301,996 $ 229,585,095 224,430,518 (ii) Noncurrent assets are not inclusive of financial instruments, deferred tax assets, and prepaid pension.
Schedule of Revenue By Major Customers	For the years ended December 31, 2017, 2018 and 2019, sales to individual customers representing greater than 10% of consolidated net revenue were as follows: For the years ended December 31, 2017 % 2018 % 2019 % (in thousands) Customer A $ 43,645,518 13 35,358,013 11 33,142,985 12
Schedule of Revenue By Products and Services	The consolidated net revenue by principal products was as follows: For the years ended December 31, 2017 2018 2019 (in thousands) Products for Televisions $ 152,442,198 113,194,567 87,269,763 Products for Mobile PCs and Devices 71,068,304 74,375,305 69,305,510 Products for Monitors 45,696,144 47,024,353 39,522,268 Products for Commercial and Others (iii) 53,128,684 56,190,529 60,569,681 Solar Products 18,692,937 16,849,635 12,124,472 Total $ 341,028,267 307,634,389 268,791,694 (iii) Others include sales from products for other applications and sales of raw materials, components and from service charges.

Changes in Significant Accoun_3

Changes in Significant Accounting Policies - Additional Information (Detail)	Jan. 01, 2019
Disclosure of initial application of standards or interpretations [line items]
Weighted average lessee's incremental borrowing rate	1.87%

Schedule of Reconciliation Betw

Schedule of Reconciliation Between Lease Liabilities Recognized and Future Minimum Lease Payments of Non-cancellable Operating Leases on Initial Application (Detail) - TWD ($) $ in Thousands	Jan. 01, 2019	Dec. 31, 2018
Disclosure of initial application of standards or interpretations [line items]
The future minimum lease payments of non-cancellable operating leases on December 31, 2018	$ 5,942,211	$ 5,942,211
Recognition exemption for short-term leases	(43,032)
Other leases in scope of IFRS 16	125,328
Undiscounted amount on January 1, 2019	6,024,507
Discounted amount using the incremental borrowing rate on January 1, 2019	5,445,818
Finance lease liabilities recognized on December 31, 2018	2,496
Extension of lease that reasonably certain to be exercised	7,241,212
Lease liabilities recognized on January 1, 2019	$ 12,689,526

Summary impacts of Company's As

Summary impacts of Company's Asset Liabilities and Equity on initial application of IFRS 16 (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disclosure of initial application of standards or interpretations [line items]
Other current assets	$ 3,295,562		$ 2,941,598
Property, plant and equipment	206,734,543		221,586,475	$ 224,933,089
Right-of-use assets	12,207,768
Other noncurrent assets	2,405,346		5,171,646
Impacts to total assets	386,356,996		398,551,180
Lease liabilities-current	682,367
Other current liabilities	18,718,165		24,291,532
Lease liabilities-noncurrent	10,408,710
Other noncurrent liabilities	1,973,459		2,029,651
Impacts to total liabilities	207,455,122		190,765,874
Impacts to total equity	$ 178,901,874		$ 207,785,306	$ 212,817,851	$ 176,836,313
Under IAS17 And Related Standards And Interpretations [member]
Disclosure of initial application of standards or interpretations [line items]
Other current assets		$ 2,941,598
Property, plant and equipment		221,586,475
Other noncurrent assets		5,171,646
Other current liabilities		24,291,532
Other noncurrent liabilities		2,029,651
Impacts to total equity		0
Carrying amount under IFRS 16 [member]
Disclosure of initial application of standards or interpretations [line items]
Other current assets		2,934,960
Property, plant and equipment		221,584,710
Right-of-use assets		14,059,544
Other noncurrent assets		3,807,535
Lease liabilities-current		708,167
Other current liabilities		24,290,601
Lease liabilities-noncurrent		11,981,359
Other noncurrent liabilities		2,028,086
Impacts to total equity		0
Increase (decrease) due to changes in accounting policy [member] | Carrying amount under IFRS 16 [member]
Disclosure of initial application of standards or interpretations [line items]
Other current assets		(6,638)
Property, plant and equipment		(1,765)
Right-of-use assets		14,059,544
Other noncurrent assets		(1,364,111)
Impacts to total assets		12,687,030
Lease liabilities-current		708,167
Other current liabilities		(931)
Lease liabilities-noncurrent		11,981,359
Other noncurrent liabilities		(1,565)
Impacts to total liabilities		12,687,030
Impacts to total equity		$ 0

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Changes in Significant Accounting Policies (Detail)		12 Months Ended
		Dec. 31, 2019		Dec. 31, 2018
AUSH [Member] | U-Fresh Technology (Suzhou) Co Ltd (UFSZ) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%	[1]
AUSH [Member] | Edgetech Data Technologies (Suzhou) Corp Ltd (EDT) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%	[1]
AUSH [Member] | Mega Insight Smart Manufacturing (Suzhou) Corp Ltd (MIS) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%	[1]
AUSH [Member] | AUO Care Information Tech (Suzhou) Co Ltd (A-Care) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
UFSZ [member] | U-Fresh Environmental Technology (Shandong) Co Ltd (UFSD) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary	[1]	100.00%
CQIL [Member] | ComQi Holdings Ltd (CQHLD) [Member] | United Kingdom [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%	[2]
CQHLD [Member] | ComQi UK Ltd (CQUK) [Member] | United Kingdom [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%	[2]
CQHLD [Member] | ComQi Inc (CQUS) [Member] | United States [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%	[2]
CQHLD [Member] | ComQi Canada Inc (CQCA) [Member] | Canada [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%	[2]
CQUS [member] | JohnRyan Limited (JRUK) [Member] | United Kingdom [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary	[1]	100.00%
CQUS [member] | JohnRyan Inc (JRUS) [Member] | United States [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary	[1]	100.00%
DPTW [Member] | Darwin Precisions (L) Corp. (DPLB) [Member] | Malaysia [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
DPTW [Member] | Forhouse International Holding Ltd. (FHVI) [Member] | BVI [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
DPTW [Member] | Force International Holding Ltd. (FRVI) [Member] | BVI [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary	[3]			100.00%
DPTW and FRVI [Member] | Forefront Corporation (FFMI) [Member] | Mauritius [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%	[3]	100.00%
FHVI [Member] | Fortech International Corp. (FTMI) [Member] | Mauritius [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
FHVI [Member] | Forward Optronics International Corp. (FWSA) [member] | Samoa [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
FHVI [Member] | Prime Forward International Ltd. (PMSA) [Member] | Samoa [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
FFMI [Member] | Forthouse Electronics (Suzhou) Co., Ltd. (FHWJ) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
FTMI [Member] | Fortech Electronics (Suzhou) Co., Ltd. (FTWJ) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
FWSA and FTMI [Member] | Suzhou Forplax Optronics Co., Ltd. (FPWJ) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
PMSA [Member] | Fortech Electronics Kunshan Co., Ltd (FTKS) [member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
DPLB [Member] | Darwin Precisions (Hong Kong) Limited (DPHK) [Member] | Hong Kong [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
DPLB [Member] | Darwin Precisions (Slovakia) s.r.o. (DPSK) [Member] | Slovakia Republic [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
DPHK [Member] | Darwin Precisions (Suzhou) Corp. (DPSZ) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
DPHK [Member] | Darwin Precisions (Xiamen) Corp. (DPXM) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
BVLB [Member] | BriView (Hefei) Co., Ltd. (BVHF) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AUO [Member] | AU Optronics (L) Corp. (AULB) [Member] | Malaysia [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AUO [Member] | Konly Venture Corp. (Konly) [Member] | Taiwan ROC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AUO [Member] | Ronly Venture Corp. (Ronly) [Member] | Taiwan ROC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AUO [Member] | Space Money Inc. (SMI) [Member] | Taiwan ROC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AUO [Member] | U-Fresh Technology Inc. (UTI) [Member] | Taiwan ROC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AUO [Member] | ComQi Ltd (CQIL) [Member] | Israel [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%	[2]
AUO [Member] | AU Optronics Europe B.V. (AUNL) [Member] | Netherlands [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%	[4]
AUO, Konly and Ronly [Member] | Darwin Precisions Corporation (DPTW) [Member] | Taiwan ROC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary	[5]	41.05%		41.05%
AUO and Konly [member] | AUO Crystal Corp. (ACTW) [Member] | Taiwan ROC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary	[6]	100.00%		96.02%
ACTW [Member] | Sanda Materials Corporation (SDMC) [Member] | Taiwan ROC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%	[7]
ACTW [Member] | AUO Crystal (Malaysia) Sdn. Bhd. (ACMK) [Member] | Malaysia [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
SDMC [Member] | M.Setek Co., Ltd. (M.Setek) [member] | Japan [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		99.9991%		99.9991%
AULB [Member] | AU Optronics Corporation America (AUUS) [Member] | United States [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AULB [Member] | AU Optronics Corporation Japan (AUJP) [Member] | Japan [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AULB [Member] | AU Optronics Korea Ltd. (AUKR) [Member] | South Korea [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AULB [Member] | AU Optronics Singapore Pte. Ltd. (AUSG) [Member] | Singapore [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AULB [Member] | AU Optronics (Czech) s.r.o. (AUCZ) [Member] | Czech Republic [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary	[3]	100.00%		100.00%
AULB [Member] | AU Optronics (Shanghai) Co., Ltd. (AUSH) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AULB [Member] | AU Optronics (Xiamen) Corp. (AUXM) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AULB [Member] | AU Optronics (Suzhou) Corp., Ltd. (AUSZ) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AULB [Member] | AU Optronics Manufacturing (Shanghai) Corp. (AUSJ) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AULB [Member] | AU Optronics (Slovakia) s.r.o. (AUSK) [Member] | Slovakia Republic [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AULB [Member] | AFPD Pte., Ltd (AUST) [Member] | Singapore [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AULB [Member] | AU Optronics (Kunshan) Co., Ltd. (AUKS) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		51.00%		51.00%
AULB [Member] | a.u. Vista Inc. (AUVI) [Member] | United States [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AULB and DPTW [Member] | BriView (L) Corp. (BVLB) [Member] | Malaysia [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AUSG [Member] | AUO Energy (Tianjin) Corp. (AETJ) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary	[3]			100.00%
AUSG [Member] | AUO Green Energy America Corp. (AEUS) [Member] | United States [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AUSG [Member] | AUO Green Energy Europe B.V. (AENL) [Member] | Netherlands [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
AUXM [Member] | BriView (Xiamen) Corp. (BVXM) [Member] | PRC [Member]
Disclosure of significant accounting policies [Line Items]
Proportion of ownership interest in subsidiary		100.00%		100.00%
[1]	UFSZ was incorporated in February 2018. EDT and MIS were incorporated in August 2018. UFSD was incorporated in May 2019. JRUK and JRUS were incorporated in October 2019.
[2]	In March 2018, the Company acquired 100% of the shareholdings of CQIL and its subsidiaries (hereinafter referred to as "ComQi") and therefore, obtained control over ComQi. Refer to note 15 for further details.
[3]	As of December 31, 2019, AETJ and FRVI were liquidated and AUCZ is still in the process of liquidation. After the liquidation of FRVI, its ownership of FFMI was transferred to DPTW.
[4]	As part of a business restructuring, AULB disposed all of its shareholdings in AUNL to AUO in December 2018. This was treated as an equity transaction as there was no change in control of AUNL by the Company.
[5]	Although the Company did not own more than 50% of the DPTW's ownership interests, it was considered to have de facto control over the main operating policies of DPTW. As a result, DPTW was accounted for as a subsidiary of the Company.
[6]	As part of a business restructuring, Konly and Ronly successively disposed its shareholdings in ACTW to AUO in December 2018 and February 2019. This was treated as an equity transaction as there was no change in control of ACTW by the Company.
[7]	As part of a business restructuring, AUO, Konly and Ronly disposed all of their shareholdings in SDMC to ACTW during the second quarter of 2018. This was treated as an equity transaction as there was no change in control of SDMC by the Company.

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2019
Bottom of range [member]
Disclosure of significant accounting policies [Line Items]
Useful lives or amortisation rates, intangible assets other than goodwill	3 years
Top of range [member]
Disclosure of significant accounting policies [Line Items]
Useful lives or amortisation rates, intangible assets other than goodwill	20 years
Machinery and equipment [member] | Bottom of range [member]
Disclosure of significant accounting policies [Line Items]
Useful lives or depreciation rates, property, plant and equipment	3 years
Machinery and equipment [member] | Top of range [member]
Disclosure of significant accounting policies [Line Items]
Useful lives or depreciation rates, property, plant and equipment	10 years
Other property, plant and equipment [member] | Bottom of range [member]
Disclosure of significant accounting policies [Line Items]
Useful lives or depreciation rates, property, plant and equipment	3 years
Other property, plant and equipment [member] | Top of range [member]
Disclosure of significant accounting policies [Line Items]
Useful lives or depreciation rates, property, plant and equipment	6 years
Buildings [member] | Bottom of range [member]
Disclosure of significant accounting policies [Line Items]
Useful lives or depreciation rates, property, plant and equipment	20 years
Buildings [member] | Top of range [member]
Disclosure of significant accounting policies [Line Items]
Useful lives or depreciation rates, property, plant and equipment	50 years

Cash and Cash Equivalents - Sch

Cash and Cash Equivalents - Schedule of Cash and Bank Balances (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disclosure of cash and cash equivalents [Abstract]
Cash on hand, demand deposits and checking accounts	$ 46,290,722	$ 30,134,051
Time deposits	34,124,011	38,939,198
Government bonds with reverse repurchase agreements	35,039	90,047
Cash and cash equivalents	$ 80,449,772	$ 69,163,296	$ 105,020,616	$ 80,191,248

Financial Assets and Liabilit_3

Financial Assets and Liabilities at Fair Value through Profit or Loss ("FVTPL") - Disclosure of Financial Instruments (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Disclosure of detailed information about financial instruments [line items]
Financial assets at fair value through profit or loss	$ 1,521,406	$ 1,709,531
Structured Deposits [Member]
Disclosure of detailed information about financial instruments [line items]
Financial assets, mandatorily measured at FVTPL	1,478,591	1,639,457
Foreign currency forward contracts [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets, mandatorily measured at FVTPL	42,815	70,074
Financial liabilities, held for trading	$ 18,859	$ 22,115

Financial Assets and Liabilit_4

Financial Assets and Liabilities at Fair Value through Profit or Loss ("FVTPL") - Schedule of Outstanding Foreign Currency Forward Contracts (Detail) € in Thousands, ¥ in Thousands, ¥ in Thousands, RM in Thousands, Kč in Thousands, $ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands

12 Months Ended

Dec. 31, 2019TWD ($)

Dec. 31, 2018TWD ($)

Dec. 31, 2019EUR (€)

Dec. 31, 2019CNY (¥)

Dec. 31, 2019USD ($)

Dec. 31, 2019JPY (¥)

Dec. 31, 2019MYR (RM)

Dec. 31, 2019SGD ($)

Dec. 31, 2019HKD ($)

Dec. 31, 2018EUR (€)

Dec. 31, 2018CNY (¥)

Dec. 31, 2018USD ($)

Dec. 31, 2018JPY (¥)

Dec. 31, 2018CZK (Kč)

Dec. 31, 2018MYR (RM)

Dec. 31, 2018SGD ($)

Sell USD / Buy NTD [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2020-01

2019-01

Contract amount

$ 5,319,611

$ 6,858,785

$ 176,600

$ 223,000

Sell USD / Buy JPY [member]

Disclosure of detailed information about financial instruments [line items]

Contract amount

47,292

¥ 5,150,510

147,470

¥ 16,493,633

Sell USD / Buy JPY [member] | Bottom of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2020-01

2019-01

Sell USD / Buy JPY [member] | Top of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2020-04

2019-04

Sell USD / Buy CNY [member]

Disclosure of detailed information about financial instruments [line items]

Contract amount

¥ 432,823

61,500

¥ 597,420

87,000

Sell USD / Buy CNY [member] | Bottom of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2020-01

2019-01

Sell USD / Buy CNY [member] | Top of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2020-06

2019-06

Sell USD / Buy SGD [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2019-01

Contract amount

39,276

$ 53,372

5,793

$ 7,940

Sell USD / Buy SGD [member] | Bottom of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2020-01

Sell USD / Buy SGD [member] | Top of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2020-02

Sell USD / Buy MYR [member]

Disclosure of detailed information about financial instruments [line items]

Contract amount

703

RM 2,905

879

RM 3,670

Sell USD / Buy MYR [member] | Bottom of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2020-01

2019-01

Sell USD / Buy MYR [member] | Top of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2020-03

2019-03

Sell CNY / Buy USD [Member]

Disclosure of detailed information about financial instruments [line items]

Contract amount

¥ 1,935,305

276,672

853,328

124,000

Sell CNY / Buy USD [Member] | Bottom of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2020-02

2019-01

Sell CNY / Buy USD [Member] | Top of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2020-03

2019-02

Sell EUR / Buy JPY [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2019-01

Contract amount

€ 23,000

¥ 2,788,285

€ 12,000

1,536,180

Sell EUR / Buy JPY [member] | Bottom of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2020-01

Sell EUR / Buy JPY [member] | Top of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2020-02

Sell HKD / Buy USD [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2020-01

Contract amount

$ 7,721

$ 60,177

Sell NTD / Buy JPY [Member]

Disclosure of detailed information about financial instruments [line items]

Contract amount

$ 2,054,260

7,400,000

Sell NTD / Buy JPY [Member] | Bottom of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2019-01

Sell NTD / Buy JPY [Member] | Top of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2019-03

Sell EUR / Buy USD [Member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2019-01

Contract amount

28,500

$ 32,441

Sell EUR / Buy CZK [member]

Disclosure of detailed information about financial instruments [line items]

Contract amount

€ 3,240

Kč 84,081

Sell EUR / Buy CZK [member] | Bottom of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2019-01

Sell EUR / Buy CZK [member] | Top of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2019-03

Sell CNY / Buy JPY [member]

Disclosure of detailed information about financial instruments [line items]

Contract amount

¥ 60,800

¥ 981,383

Sell CNY / Buy JPY [member] | Bottom of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2019-01

Sell CNY / Buy JPY [member] | Top of range [member]

Disclosure of detailed information about financial instruments [line items]

Derivative Financial Instrument Maturity date

2019-02

Financial Assets at Fair Valu_3

Financial Assets at Fair Value through Other Comprehensive Income ("FVTOCI") - Disclosure of Fair Value of Investments in Equity Instruments Designated at Fair Value Through Other Comprehensive Income (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Disclosure of detailed information about financial instruments [line items]
Investments in equity instruments at FVTOCI	$ 7,545,171	$ 6,979,925
Equity securities - listed stocks [Member]
Disclosure of detailed information about financial instruments [line items]
Investments in equity instruments at FVTOCI	7,356,501	6,803,900
Equity securities - non-listed stocks [Member]
Disclosure of detailed information about financial instruments [line items]
Investments in equity instruments at FVTOCI	$ 188,670	$ 176,025

Financial Assets at Fair Valu_4

Financial Assets at Fair Value through Other Comprehensive Income ("FVTOCI") - Additional Information (Detail) - Equity price risk [member] - FVTOCI [member] - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019
Disclosure of detailed information about financial instruments [line items]
Assumed change in risk	10.00%
Assumed change in risk, monetary effect	$ 697,993	$ 754,517

Available-for-sale Financial _2

Available-for-sale Financial Assets-noncurrent - Additional Information (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of available-for-sale financial assets [Line Items]
Impairment loss	$ 2,298,646	$ 399,363	$ 1,046,668
Financial assets available-for-sale [member]
Disclosure of available-for-sale financial assets [Line Items]
Impairment loss			30,000
Equity price risk [member] | AFS [Member]
Disclosure of available-for-sale financial assets [Line Items]
Amount of sensitivity of equity securities to changes in share price			$ 417,032
Appreciation Or Depreciation Rate On Equity Price			10.00%

Accounts Receivable, net (Inc_3

Accounts Receivable, net (Including Related and Unrelated Parties) - Schedule of Trade Receivables (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of Notes and Accounts Receivable [Abstract]
Accounts receivable	$ 32,104,912	$ 47,453,087
Less: loss allowance	(17,738)	(50,853)	$ (93,053)
Accounts Receivable, Net Including Related Parties	32,087,174	47,402,234
Accounts receivable, net	30,308,675	44,647,981
Accounts receivable from related parties, net	$ 1,778,499	$ 2,754,253

Accounts Receivable, net (Inc_4

Accounts Receivable, net (Including Related and Unrelated Parties) (Details 1) (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Disclosure of Notes and Accounts Receivable [Line Items]
Carrying amount of accounts receivable	$ 32,087,324	$ 47,403,346
Loss allowance for lifetime expected credit losses	150	1,112
Not past due [member]
Disclosure of Notes and Accounts Receivable [Line Items]
Carrying amount of accounts receivable	$ 31,061,173	$ 46,529,408
Weighted-average loss rate	0.00%	0.00%
Loss allowance for lifetime expected credit losses	$ 1	$ 89
Past due less than 60 days [member]
Disclosure of Notes and Accounts Receivable [Line Items]
Carrying amount of accounts receivable	$ 1,010,918	$ 862,373
Weighted-average loss rate	0.00%	0.05%
Loss allowance for lifetime expected credit losses	$ 4	$ 439
Past due 61~180 days [member]
Disclosure of Notes and Accounts Receivable [Line Items]
Carrying amount of accounts receivable	$ 15,233	$ 11,090
Weighted-average loss rate	0.95%	0.98%
Loss allowance for lifetime expected credit losses	$ 145	$ 109
Past due over 180 days [member]
Disclosure of Notes and Accounts Receivable [Line Items]
Carrying amount of accounts receivable		$ 475
Weighted-average loss rate		100.00%
Loss allowance for lifetime expected credit losses		$ 475

Accounts Receivable, net (Inc_5

Accounts Receivable, net (Including Related and Unrelated Parties) - Additional Information (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019TWD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018TWD ($)	Dec. 31, 2017TWD ($)
Disclosure of Accounts Receivable [Line Items]
Allowance account for credit losses of financial assets	$ 17,738		$ 50,853	$ 93,053
Trade receivables	$ 32,104,912		47,453,087
Individually assessed for impairment [member]
Disclosure of Accounts Receivable [Line Items]
Allowance account for credit losses of financial assets		$ 17,588	49,741
Individually assessed for impairment [member] | Gross carrying amount [member]
Disclosure of Accounts Receivable [Line Items]
Trade receivables		$ 17,588	$ 49,741
Bottom of range [member]
Disclosure of Accounts Receivable [Line Items]
Payment terms granted to customers	25 days
Top of range [member]
Disclosure of Accounts Receivable [Line Items]
Payment terms granted to customers	60 days

Accounts Receivable, net (Inc_6

Accounts Receivable, net (Including Related and Unrelated Parties) - Schedule of Loss Allowance for Accounts Receivable (Detail) - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of Notes and Accounts Receivable [Line Items]
Balance at beginning of the year		$ 50,853	$ 93,053
Provisions (reversals) charged to (against) expense		(14,543)	(24,302)
Write-offs		(18,404)	(17,985)
Effect of changes in foreign currency exchange rates		(168)	87
Balance at end of the year		$ 17,738	50,853	$ 93,053
Expected credit losses individually assessed [member]
Disclosure of Notes and Accounts Receivable [Line Items]
Balance at beginning of the year	[1]		12,765	41,812
Provisions (reversals) charged to (against) expense	[1]			(28,236)
Write-offs	[1]			(6)
Effect of changes in foreign currency exchange rates	[1]			(805)
Balance at end of the year	[1]			12,765
Expected credit losses collectively assessed [member]
Disclosure of Notes and Accounts Receivable [Line Items]
Balance at beginning of the year	[1]		$ 80,288	62,805
Provisions (reversals) charged to (against) expense	[1]			18,396
Write-offs	[1]			0
Effect of changes in foreign currency exchange rates	[1]			(913)
Balance at end of the year	[1]			$ 80,288
[1]	The movement of 2017 was under IAS 39. There were no adjustments for the beginning balance of 2018 on the initial application of IFRS 9.

Accounts Receivable, net (Inc_7

Accounts Receivable, net (Including Related and Unrelated Parties) - Schedule of Trade Receivables Factoring (Detail) - 12 months ended Dec. 31, 2019 $ in Thousands, $ in Thousands	USD ($)	TWD ($)	USD ($)
CTBC Bank [member]
Disclosure of Notes and Accounts Receivable [Line Items]
Factoring limit			$ 152,000
Amount sold and derecognized	$ 18,526
Amount advanced		$ 500,000
Principal terms	See Notes(a)~(d)
Taipei Fubon Bank [member]
Disclosure of Notes and Accounts Receivable [Line Items]
Factoring limit			120,000
Amount sold and derecognized	$ 56,020
Amount advanced		1,500,000
Principal terms	See Notes(a)~(d)
Dbs Bank [member]
Disclosure of Notes and Accounts Receivable [Line Items]
Factoring limit			154,000
Amount sold and derecognized	$ 56,730
Amount advanced		1,520,000
Principal terms	See Notes(a)~(d)
Bank of Taiwan [member]
Disclosure of Notes and Accounts Receivable [Line Items]
Factoring limit			$ 250,000
Amount sold and derecognized	$ 15,718
Amount advanced		$ 14,000
Principal terms	See Notes(a)~(d)

Accounts Receivable, net (Inc_8

Accounts Receivable, net (Including Related and Unrelated Parties) - Schedule of Trade Receivables Factoring (Parenthetical) (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019TWD ($)
Other current financial assets [member]
Disclosure of Notes and Accounts Receivable [Line Items]
Net of fees charged by underwriting banks	$ 487,754
Bottom of range [member] | Factoring of receivables [member]
Disclosure of Notes and Accounts Receivable [Line Items]
Interest rate	1.07%
Top of range [member] | Factoring of receivables [member]
Disclosure of Notes and Accounts Receivable [Line Items]
Interest rate	2.44%

Inventories - Schedule Of Inven

Inventories - Schedule Of Inventory (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Disclosure of Inventories [Abstract]
Finished goods	$ 9,005,001	$ 9,406,248
Work-in-progress	9,537,700	11,133,846
Raw materials	4,917,371	5,769,010
Total	$ 23,460,072	$ 26,309,104

Inventories - Additional Inform

Inventories - Additional Information (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of Inventories [Abstract]
Amount of inventories recognised as cost of sales during period	$ 268,335,751	$ 279,494,885	$ 279,986,522
Inventory write-down	$ 5,185,504	$ 5,171,752	$ 3,756,726

Noncurrent Assets Held for Sa_2

Noncurrent Assets Held for Sale - Additional Information (Detail) - TWD ($) $ in Thousands	1 Months Ended		6 Months Ended	12 Months Ended
	Jun. 30, 2018	Mar. 31, 2018	Aug. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Noncurrent Assets Held For Sale [Line Items]
Gains (losses) on disposals of property, plant and equipment				$ 106,546	$ 1,923,044	$ 330,814
Fortech Electronics Kunshan Co., Ltd (FTKS) [member] | Non-current assets held for sale [member]
Disclosure Of Noncurrent Assets Held For Sale [Line Items]
Proceeds from disposal of non-current assets or disposal groups classified as held for sale and discontinued operations		$ 983,082
Gains (losses) on disposals of property, plant and equipment		$ 561,815
BriView (Hefei) Co., Ltd. (BVHF) [Member] | Non-current assets held for sale [member]
Disclosure Of Noncurrent Assets Held For Sale [Line Items]
Proceeds from disposal of non-current assets or disposal groups classified as held for sale and discontinued operations	$ 2,204,576
Gains (losses) on disposals of property, plant and equipment	$ 228,754
M.Setek Co., Ltd. (M.Setek) [member] | Non-current assets held for sale [member]
Disclosure Of Noncurrent Assets Held For Sale [Line Items]
Proceeds from disposal of non-current assets or disposal groups classified as held for sale and discontinued operations			$ 837,103
Gains (losses) on disposals of property, plant and equipment			$ 215,478

Investments in equity-account_3

Investments in equity-accounted Investees - Schedule of Interests in Other Entities (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Disclosure of Investments in equity-accounted Investees [Abstract]
Associates	$ 5,820,759	$ 5,973,127
Joint ventures	178,720	312,738
Total	$ 5,999,479	$ 6,285,865

Investments in equity-account_4

Investments in equity-accounted Investees - Schedule of Interests in Associates (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disclosure of Investments in equity-accounted Investees [Line Items]
Investments in associates	$ 5,820,759	$ 5,973,127
Lextar Electronics Corp [member]
Disclosure of Investments in equity-accounted Investees [Line Items]
Principal activities of business associate	Manufacturing and sales of Light Emitting Diode
Principal place of business of associate	Taiwan ROC
Proportion of ownership interest in associate	27.00%	27.00%
Investments in associates	$ 2,909,521	$ 3,082,178
Star Shining Energy Corporation [member]
Disclosure of Investments in equity-accounted Investees [Line Items]
Principal activities of business associate	Investment
Principal place of business of associate	Taiwan ROC
Proportion of ownership interest in associate	33.00%	33.00%
Investments in associates	$ 1,015,512	$ 1,002,874
Raydium Semiconductor Corporation [member]
Disclosure of Investments in equity-accounted Investees [Line Items]
Principal activities of business associate	IC design
Principal place of business of associate	Taiwan ROC
Proportion of ownership interest in associate	17.00%	18.00%
Investments in associates	$ 740,504	$ 716,381
Daxin Materials Corp [member]
Disclosure of Investments in equity-accounted Investees [Line Items]
Principal activities of business associate	Research, manufacturing, and sales of display related chemicals
Principal place of business of associate	Taiwan ROC
Proportion of ownership interest in associate	25.00%	25.00%
Investments in associates	$ 688,813	$ 654,940
Star River Energy Corporation [member]
Disclosure of Investments in equity-accounted Investees [Line Items]
Principal activities of business associate	Investment
Principal place of business of associate	Taiwan ROC
Proportion of ownership interest in associate	34.00%	34.00%
Investments in associates	$ 444,550	$ 434,421
Other associate [member]
Disclosure of Investments in equity-accounted Investees [Line Items]
Investments in associates	$ 21,859	$ 82,333

Investments in equity-account_5

Investments in equity-accounted Investees - Summary of Investment in Associates Amount Recognized (Detail) - Associates [member] - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of Investments in equity-accounted Investees [Line Items]
The Company's share of profits of associates	$ 195,865	$ 307,992	$ 251,699
The Company's share of other comprehensive loss of associates	(35,224)	(15,477)	(62,084)
The Company's share of total comprehensive income (loss) of associates	$ 160,641	$ 292,515	$ 189,615

Investments in equity-account_6

Investments in equity-accounted Investees - Schedule of Joint Ventures (Detail) - Joint ventures [member] - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of Investments in equity-accounted Investees [Line Items]
The Company's share of profits (losses) of joint ventures	$ (45,958)	$ 3,722	$ (12,693)
The Company's share of other comprehensive loss of joint ventures	0	0	0
The Company's share of total comprehensive income (loss) of joint ventures	$ (45,958)	$ 3,722	$ (12,693)

Acquisition of Subsidiaries - A

Acquisition of Subsidiaries - Additional Information (Detail) - ComQi Ltd. and its subsidiaries ("ComQi") [member] - TWD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2018
Disclosure of detailed information about business combination [line items]
Date of acquisition	Mar. 31, 2018
Description of acquiree	ComQi is engaged in integration service of content management system and hardware.
Proportion of voting equity interests acquired	100.00%
Net revenue of combined entity		$ 307,673,560
Profit (loss) of combined entity		7,956,563
Acquisition-related costs		$ 12,191
Contingent Consideration Arrangements [Member]
Disclosure of detailed information about business combination [line items]
Description of basis for determining amount of payment for contingent consideration arrangements		in the event that ComQi's annual net revenue and annual recurring revenue for the year ended December 31, 2018 are greater than the agreed revenue targets in the agreement, the Company should pay additional consideration of USD4,000 thousand and USD7,000 thousand, respectively, to the original shareholders of ComQi.
Description of estimate of range of undiscounted outcomes from contingent consideration arrangements		USD0 and USD11,000
Fair value discount rate	8.50%
Revenue volatility rate	30.80%
Credit spread	0.88%
Contingent consideration arrangements and indemnification assets recognised as of acquisition date	$ 283,354

Acquisition of Subsidiaries - S

Acquisition of Subsidiaries - Summary of Consideration Transferred (Detail) - ComQi Ltd. and its subsidiaries ("ComQi") [member] $ in Thousands	Mar. 31, 2018TWD ($)
Acquisition-date fair value of total consideration transferred [abstract]
Cash	$ 467,920
Contingent consideration	283,354
Consideration transferred, acquisition-date fair value	$ 751,274

Acquisition of Subsidiaries -_2

Acquisition of Subsidiaries - Summary of Identifiable Assets Acquired and Liabilities Assumed (Detail) - ComQi Ltd. and its subsidiaries ("ComQi") [member] $ in Thousands	Mar. 31, 2018TWD ($)
Amounts recognised as of acquisition date for each major class of assets acquired and liabilities assumed [abstract]
Cash	$ 19,432
Accounts receivable and other current assets	36,851
Property, plant and equipment	3,712
Intangible assets	150,436
Accounts payable and other current liabilities	(57,361)
Other liabilities	(2,120)
Total	$ 150,950

Acquisition of Subsidiaries -_3

Acquisition of Subsidiaries - Summary of Goodwill Acquired (Detail) - ComQi Ltd. and its subsidiaries ("ComQi") [member] $ in Thousands	Mar. 31, 2018TWD ($)
Disclosure of detailed information about business combination [line items]
Consideration transferred	$ 751,274
Less: Fair value of identifiable net assets	(150,950)
Goodwill recognised as of acquisition date	$ 600,324

Disposal of Part of Ownership_3

Disposal of Part of Ownership Interest in Subsidiary without Losing Control - Additional Information (Detail) $ in Thousands	1 Months Ended
	Nov. 30, 2017TWD ($)
Disclosure Of Disposal of Part of Ownership Interest in Subsidiary without Losing Control [Abstract]
Proportion Of Subsidiary Ownership Percentage Sold	9.99%
Total cash consideration received	$ 1,776,984

Disposal of Part of Ownership_4

Disposal of Part of Ownership Interest in Subsidiary without Losing Control - Summary of consideration (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2017TWD ($)
Disclosure Of Disposal of Part of Ownership Interest in Subsidiary without Losing Control [Abstract]
Consideration received	$ 1,776,984
Carrying amount of the equity interest disposed of	(1,190,529)
Capital surplus - changes in ownership interest of subsidiary	(12,099)
Other equity - effect from foreign currency translation differences arising from foreign operations	(56,160)
Capital surplus - differences between consideration and carrying amount arising from disposal of interest in subsidiary	$ 518,196

Disposal of Subsidiaries - Addi

Disposal of Subsidiaries - Additional Information (Detail) - Star Shining Energy Corporation [member] - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Fargen Power Corporation and TronGen Power Corporation [Member]
Disposal of Subsidiaries [Line Items]
Cash consideration received		$ 480,000
Gains on disposal of subsidiaries		$ 76,331
ChampionGen Power Corporation [Member]
Disposal of Subsidiaries [Line Items]
Cash consideration received	$ 116,000
Gains on disposal of subsidiaries	$ 17,269

Disposal of Subsidiaries - Disc

Disposal of Subsidiaries - Disclosure of Detailed Information About Carrying Value of Assets and Liabilities in Subsidiary or Businesses Acquired or Disposed (Detail) - Buyer SSEC [Member] - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Fargen Power Corporation and TronGen Power Corporation [Member]
Disposal of Subsidiaries [Line Items]
Cash and cash equivalents		$ 203,607
Accounts receivable and other receivables		4,513
Other current assets		38,649
Property, plant and equipment		260,828
Other assets		54,397
Payable for equipment		(71,076)
Accrued expense and other current liabilities		(3,062)
Long-term borrowings		(84,187)
Net assets disposed of		$ 403,669
ChampionGen Power Corporation [Member]
Disposal of Subsidiaries [Line Items]
Cash and cash equivalents	$ 70,516
Other current assets	48,148
Payable for equipment	(19,933)
Net assets disposed of	$ 98,731

Property, Plant and Equipment -

Property, Plant and Equipment - Schedule of Property Plant and Equipment (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disclosure of detailed information about property, plant and equipment [line items]
Balance, Beginning of Year	$ 221,586,475	$ 224,933,089
Balance, End of Year	206,734,543	221,586,475
Gross carrying amount [member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, Beginning of Year	1,001,141,427	962,542,986
Adjustment on initial application of new standards	(2,620)
Additions	6,556,604	7,276,801
Disposal or write off	(14,896,737)	(20,372,754)
Reclassification, effect of change in exchange rate and others	13,173,497	51,694,394
Balance, End of Year	1,005,972,171	1,001,141,427
Accumulated depreciation, amortisation and impairment [member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, Beginning of Year	785,955,661	764,877,366
Adjustment on initial application of new standards	(855)
Additions	37,119,138	34,085,924
Disposal or write off	(14,837,239)	(16,358,967)
Reclassification, effect of change in exchange rate and others	(4,126,719)	3,351,338
Balance, End of Year	804,109,986	785,955,661
Land [member] | Gross carrying amount [member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, Beginning of Year	8,859,323	9,008,659
Additions		0
Disposal or write off		(161,728)
Reclassification, effect of change in exchange rate and others	(675)	12,392
Balance, End of Year	8,858,648	8,859,323
Buildings [member] | Gross carrying amount [member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, Beginning of Year	121,219,360	124,010,869
Additions	325,184	53,706
Disposal or write off	(9,075)	(5,271,527)
Reclassification, effect of change in exchange rate and others	(1,838,220)	2,426,312
Balance, End of Year	119,697,249	121,219,360
Buildings [member] | Accumulated depreciation, amortisation and impairment [member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, Beginning of Year	36,031,326	33,825,375
Additions	4,195,265	3,097,807
Disposal or write off	(9,021)	(1,754,678)
Reclassification, effect of change in exchange rate and others	(1,046,822)	862,822
Balance, End of Year	39,170,748	36,031,326
Machinery and equipment [member] | Gross carrying amount [member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, Beginning of Year	835,933,620	800,164,310
Additions	1,320,958	2,145,769
Disposal or write off	(9,123,165)	(13,164,282)
Reclassification, effect of change in exchange rate and others	13,450,424	46,787,823
Balance, End of Year	841,581,837	835,933,620
Machinery and equipment [member] | Accumulated depreciation, amortisation and impairment [member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, Beginning of Year	721,833,348	707,334,411
Additions	27,348,497	25,620,993
Disposal or write off	(9,080,856)	(12,828,449)
Reclassification, effect of change in exchange rate and others	(2,808,161)	1,706,393
Balance, End of Year	737,292,828	721,833,348
Other equipment [member] | Gross carrying amount [member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, Beginning of Year	35,129,124	29,359,148
Adjustment on initial application of new standards	(2,620)
Additions	4,910,462	5,077,326
Disposal or write off	(5,764,497)	(1,775,217)
Reclassification, effect of change in exchange rate and others	1,561,968	2,467,867
Balance, End of Year	35,834,437	35,129,124
Other equipment [member] | Accumulated depreciation, amortisation and impairment [member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, Beginning of Year	28,090,987	23,717,580
Adjustment on initial application of new standards	(855)
Additions	5,575,376	5,367,124
Disposal or write off	(5,747,362)	(1,775,840)
Reclassification, effect of change in exchange rate and others	(271,736)	782,123
Balance, End of Year	27,646,410	28,090,987
Prepayments for purchase of land and equipment, and construction in progress [member] | Accumulated depreciation, amortisation and impairment [member]
Disclosure of detailed information about property, plant and equipment [line items]
Balance, Beginning of Year	6,400,709	27,267,469
Additions	18,469,787	26,228,260
Disposal or write off	(4,837)	0
Reclassification, effect of change in exchange rate and others	(19,993,301)	(47,095,020)
Balance, End of Year	$ 4,872,358	$ 6,400,709

Property, Plant and Equipment_2

Property, Plant and Equipment - Additional Information (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of detailed information about property, plant and equipment [line items]
Property, plant and equipment	$ 206,734,543	$ 221,586,475	$ 224,933,089
Proceeds from sales of property, plant and equipment, classified as investing activities	170,880	6,408,057	1,149,649
Display segment [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Impairment loss recognised in profit or loss, property, plant and equipment	52,829		895,954
Energy segment [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Impairment loss recognised in profit or loss, property, plant and equipment	14,949	399,363	$ 120,714
ACTW and Its subsidiaries [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Impairment loss recognised in profit or loss, property, plant and equipment	$ 2,232,739
Pre-tax discount rate for calculating estimated recoverable amount	10.63%
AUSK [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Proceeds from sales of property, plant and equipment, classified as investing activities		3,029,191
Gains on disposals of property, plant and equipment		1,080,720
Non-irrigated farmland [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Property, plant and equipment	$ 23,671	$ 23,671

Property, Plant and Equipment_3

Property, Plant and Equipment - Summarized Capitalized Borrowing Costs and Interest Rate (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of detailed information about property, plant and equipment [line items]
Capitalized borrowing costs	$ 141,966	$ 421,618	$ 624,235
Bottom of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Interest rate range	1.07%	1.04%	1.09%
Top of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Interest rate range	5.71%	5.59%	5.24%

Lease Arrangements - Schedule O

Lease Arrangements - Schedule Of Quantitative Information Right Of Use Assets (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019TWD ($)
Disclosure of quantitative information about right-of-use assets [line items]
Carrying amount of right-of-use assets	$ 12,207,768
Additions to right-of-use assets	192,655
Depreciation charge for right-of-use assets	872,541
Land [member]
Disclosure of quantitative information about right-of-use assets [line items]
Carrying amount of right-of-use assets	11,595,815
Depreciation charge for right-of-use assets	566,982
Buildings [member]
Disclosure of quantitative information about right-of-use assets [line items]
Carrying amount of right-of-use assets	575,724
Depreciation charge for right-of-use assets	238,969
Other equipment [member]
Disclosure of quantitative information about right-of-use assets [line items]
Carrying amount of right-of-use assets	36,229
Depreciation charge for right-of-use assets	$ 66,590

Lease Arrangements - Schedule_2

Lease Arrangements - Schedule of Quantitative Information Lease liabilities (Detail) $ in Thousands	Dec. 31, 2019TWD ($)
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Future minimum lease payments	$ 13,342,287
Interests	2,251,210
Present value of minimum lease payments	11,091,077
Lease liabilities-current	682,367
Lease liabilities-noncurrent	10,408,710
Less than one year [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Future minimum lease payments	879,518
Interests	197,151
Present value of minimum lease payments	682,367
Between one and five years [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Future minimum lease payments	2,874,682
Interests	678,576
Present value of minimum lease payments	2,196,106
More than five years [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Future minimum lease payments	9,588,087
Interests	1,375,483
Present value of minimum lease payments	$ 8,212,604

Lease Arrangements - Additional

Lease Arrangements - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019TWD ($)
Disclosure of quantitative information about leases for lessee [abstract]
Decrease in carrying amount of right-of-use asset due to modified lease contracts	$ 1,064,094
Income from subleasing right-of-use assets	8,199
Cash out flow for leases as a lessee	920,666
Operating lease direct cost	$ 3,007

Lease Arrangements - Schedule_3

Lease Arrangements - Schedule of Additional Information about Lease (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019TWD ($)
Disclosure of quantitative information about leases for lessee [abstract]
Expenses relating to short-term leases	$ 15,832
Expenses relating to leases of low-value assets, excluding short-term leases of low-value assets	$ 315

Lease Arrangements - Lease Arra

Lease Arrangements - Lease Arrangements - Schedule of Maturity Analysis of Undiscounted Operating Lease Receivable (Detail) $ in Thousands	Dec. 31, 2019TWD ($)
Disclosure of maturity analysis of operating lease payments [line items]
Total undiscounted operating lease receivable	$ 2,623,088
Less than one year [member]
Disclosure of maturity analysis of operating lease payments [line items]
Total undiscounted operating lease receivable	110,905
Later than one year and not later than two years [member]
Disclosure of maturity analysis of operating lease payments [line items]
Total undiscounted operating lease receivable	110,316
Later than two years and not later than three years [member]
Disclosure of maturity analysis of operating lease payments [line items]
Total undiscounted operating lease receivable	110,025
Later than three years and not later than four years [member]
Disclosure of maturity analysis of operating lease payments [line items]
Total undiscounted operating lease receivable	106,272
Later than four years and not later than five years [member]
Disclosure of maturity analysis of operating lease payments [line items]
Total undiscounted operating lease receivable	105,721
More than five years [member]
Disclosure of maturity analysis of operating lease payments [line items]
Total undiscounted operating lease receivable	$ 2,079,849

Investment Property - Summary o

Investment Property - Summary of Investment property (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disclosure of detailed information about investment property [line items]
Balance, Beginning of Year	$ 730,306
Balance, End of Year	1,555,130	$ 730,306
Net asset value [member]
Disclosure of detailed information about investment property [line items]
Balance, Beginning of Year	730,306
Balance, End of Year	1,555,130	730,306
Accumulated Depreciation [member]
Disclosure of detailed information about investment property [line items]
Additions	7,665
Reclassification and effect of change in exchange rate	614,066
Balance, End of Year	621,731
Right-of-use assets [member] | Accumulated Depreciation [member]
Disclosure of detailed information about investment property [line items]
Additions	302
Reclassification and effect of change in exchange rate	1,448
Balance, End of Year	1,750
Buildings [member] | Accumulated Depreciation [member]
Disclosure of detailed information about investment property [line items]
Additions	7,363
Reclassification and effect of change in exchange rate	612,618
Balance, End of Year	619,981
At cost [member]
Disclosure of detailed information about investment property [line items]
Balance, Beginning of Year	730,306	717,823
Reclassification and effect of change in exchange rate	1,446,555	12,483
Balance, End of Year	2,176,861	730,306
At cost [member] | Right-of-use assets [member]
Disclosure of detailed information about investment property [line items]
Reclassification and effect of change in exchange rate	28,570
Balance, End of Year	28,570
At cost [member] | Land [member]
Disclosure of detailed information about investment property [line items]
Balance, Beginning of Year	730,306
Reclassification and effect of change in exchange rate	(667)
Balance, End of Year	729,639	730,306
At cost [member] | Buildings [member]
Disclosure of detailed information about investment property [line items]
Reclassification and effect of change in exchange rate	1,418,652
Balance, End of Year	1,418,652
At fair value [member]
Disclosure of detailed information about investment property [line items]
Balance, Beginning of Year	2,252,170	2,213,184
Balance, End of Year	$ 4,057,848	$ 2,252,170

Investment Property - Additiona

Investment Property - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019TWD ($)
Disclosure of detailed information about investment property [abstract]
Transfer from property, plant and equipment to investment property	$ 832,886

Investment Property - Significa

Investment Property - Significant Inputs Used in Fair Value Measurement (Detail)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disclosure of detailed information about investment property [line items]
Rate of return	15.00%	10.00%
Capitalization rate		12.00%
Interest rate, measurement input [member]
Disclosure of detailed information about investment property [line items]
Overall capital interest rate	2.53%	1.86%
Bottom of range [member]
Disclosure of detailed information about investment property [line items]
Capitalization rate	8.00%
Top of range [member]
Disclosure of detailed information about investment property [line items]
Capitalization rate	12.00%

Intangible Assets - Summary of

Intangible Assets - Summary of Intangible Assets (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disclosure of detailed information about intangible assets [line items]
Balance, Beginning of Year	$ 2,096,668	$ 1,890,297
Balance, End of Year	1,527,731	2,096,668
Gross carrying amount [member]
Disclosure of detailed information about intangible assets [line items]
Balance, Beginning of Year	13,022,502	12,275,548
Additions	1,711
Effect of change in consolidated entities		750,760
Effect of change in exchange rate	(7,140)	(3,806)
Balance, End of Year	13,017,073	13,022,502
Gross carrying amount [member] | Goodwill [Member]
Disclosure of detailed information about intangible assets [line items]
Balance, Beginning of Year	600,324
Effect of change in consolidated entities		600,324
Balance, End of Year	600,324	600,324
Gross carrying amount [member] | Other Intangible Assets [Member]
Disclosure of detailed information about intangible assets [line items]
Balance, Beginning of Year	150,436
Effect of change in consolidated entities		150,436
Balance, End of Year	150,436	150,436
Gross carrying amount [member] | Patent and technology fee [Member]
Disclosure of detailed information about intangible assets [line items]
Balance, Beginning of Year	12,271,742	12,275,548
Additions	1,711
Effect of change in exchange rate	(7,140)	(3,806)
Balance, End of Year	12,266,313	12,271,742
Accumulated depreciation, amortisation and impairment [member]
Disclosure of detailed information about intangible assets [line items]
Balance, Beginning of Year	10,925,834	10,385,251
Additions	564,686	540,969
Effect of change in exchange rate	(1,178)	(386)
Balance, End of Year	11,489,342	10,925,834
Accumulated depreciation, amortisation and impairment [member] | Other Intangible Assets [Member]
Disclosure of detailed information about intangible assets [line items]
Balance, Beginning of Year	22,565
Additions	127,871	22,565
Balance, End of Year	150,436	22,565
Accumulated depreciation, amortisation and impairment [member] | Patent and technology fee [Member]
Disclosure of detailed information about intangible assets [line items]
Balance, Beginning of Year	10,903,269	10,385,251
Additions	436,815	518,404
Effect of change in exchange rate	(1,178)	(386)
Balance, End of Year	$ 11,338,906	$ 10,903,269

Intangible Assets - Summary o_2

Intangible Assets - Summary of information of the operating business that the company's goodwill allocated to (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Member]
Disclosure of detailed information about intangible assets [line items]
Display business	$ 600,324	$ 600,324

Intangible Assets - Additional

Intangible Assets - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disclosure of detailed information about intangible assets [abstract]
Description of discount rate on which management has based cash flow projections	12.25	11.57
Description of annual terminal growth rate on which management has based cash flow projections	(0.50%)	(1.00%)

Other Current Assets and Othe_3

Other Current Assets and Other Non current Assets - Schedule of Other Assets (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Other Current Assets and Other Noncurrent Assets [Line Items]
Other Assets	$ 5,700,908	$ 8,113,244
Less: current	(3,295,562)	(2,941,598)
Noncurrent	2,405,346	5,171,646
Refundable and overpaid tax [Member]
Other Current Assets and Other Noncurrent Assets [Line Items]
Other Assets	1,458,170	1,351,646
Refundable deposits [Member]
Other Current Assets and Other Noncurrent Assets [Line Items]
Other Assets	663,911	716,097
Prepayment for equipment [Member]
Other Current Assets and Other Noncurrent Assets [Line Items]
Other Assets	453,300	650,727
Prepayments for purchases [Member]
Other Current Assets and Other Noncurrent Assets [Line Items]
Other Assets	158,521	230,793
Long-term receivables [Member]
Other Current Assets and Other Noncurrent Assets [Line Items]
Other Assets	5,812	930,001
Long-term prepaid rents [Member]
Other Current Assets and Other Noncurrent Assets [Line Items]
Other Assets		1,364,111
Others [Member]
Other Current Assets and Other Noncurrent Assets [Line Items]
Other Assets	$ 2,961,194	$ 2,869,869

Short-term Borrowings - Schedul

Short-term Borrowings - Schedule of Short Term Borrowings (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Disclosure of detailed information about short term borrowings [Line Items]
Short-term borrowings	$ 1,725,602	$ 546,472
Unsecured Borrowings [Member]
Disclosure of detailed information about short term borrowings [Line Items]
Short-term borrowings	1,725,602	546,472
Unused Credit Facility [Member]
Disclosure of detailed information about short term borrowings [Line Items]
Unused credit facilities	$ 37,982,721	$ 43,533,037
Short-term borrowings [Member] | Bottom of range [member]
Disclosure of detailed information about short term borrowings [Line Items]
Interest rate range	1.20%	2.54%
Short-term borrowings [Member] | Top of range [member]
Disclosure of detailed information about short term borrowings [Line Items]
Interest rate range	4.35%	4.35%

Long-term Borrowings - Schedule

Long-term Borrowings - Schedule of Long-term Borrowings (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Disclosure of detailed information about long term borrowings [Line Items]
Current and Non current portion of long term barrowings	$ 112,223,068	$ 86,782,088
Less: transaction costs	(254,676)	(476,770)
Borrowings	111,968,392	86,305,318
Less: current portion	(9,535,198)	(29,595,931)
Non-current portion of non-current borrowings	102,433,194	56,709,387
Unsecured loans [member]
Disclosure of detailed information about long term borrowings [Line Items]
Current and Non current portion of long term barrowings	8,050,310	2,976,158
Secured loans [member]
Disclosure of detailed information about long term borrowings [Line Items]
Current and Non current portion of long term barrowings	7,671,932	1,990,175
Long-term borrowings [member]
Disclosure of detailed information about long term borrowings [Line Items]
Unused credit facilities	$ 32,265,575	$ 79,933,812
Bottom of range [member] | Long-term borrowings [member]
Disclosure of detailed information about long term borrowings [Line Items]
Borrowings, interest rate	1.00%	1.07%
Top of range [member] | Long-term borrowings [member]
Disclosure of detailed information about long term borrowings [Line Items]
Borrowings, interest rate	5.43%	6.32%
Repayment duration From Feb. 2019 to Feb. 2024 [member] | Syndicated loans [member]
Disclosure of detailed information about long term borrowings [Line Items]
Current and Non current portion of long term barrowings	$ 42,000,000
Repayment duration From Mar. 2019 to Apr. 2023 [member] | Syndicated loans [member]
Disclosure of detailed information about long term borrowings [Line Items]
Current and Non current portion of long term barrowings	23,000,000
Repayment duration From May. 2017 to May. 2022 [member] | Syndicated loans [member]
Disclosure of detailed information about long term borrowings [Line Items]
Current and Non current portion of long term barrowings	10,000,000	$ 10,000,000
Repayment duration From Apr. 2016 to Apr. 2019 [member] | Syndicated loans [member]
Disclosure of detailed information about long term borrowings [Line Items]
Current and Non current portion of long term barrowings		36,175,000
Repayment duration From Feb. 2015 to Feb. 2019 [member] | Syndicated loans [member]
Disclosure of detailed information about long term borrowings [Line Items]
Current and Non current portion of long term barrowings		5,912,000
Repayment duration From Jul. 2018 to Oct. 2019 [member] | Syndicated loans [member]
Disclosure of detailed information about long term borrowings [Line Items]
Current and Non current portion of long term barrowings		210,000
Repayment duration From Feb. 2016 to Jan. 2019 [member] | Syndicated loans [member]
Disclosure of detailed information about long term borrowings [Line Items]
Current and Non current portion of long term barrowings		1,775,236
Repayment duration From Nov. 2015 to Nov. 2023 [member] | Syndicated loans [member]
Disclosure of detailed information about long term borrowings [Line Items]
Current and Non current portion of long term barrowings	$ 21,500,826	$ 27,743,519

Provisions - Schedule of Provis

Provisions - Schedule of Provisions (Detail) - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018
Disclosure of movements in provisions [Line Items]
Balance at beginning of the year		$ 2,538,049	$ 1,885,963
Additions		566,735	1,184,020
Usage		(643,158)	(446,951)
Reversals		(683,525)	(100,969)
Effect of change in exchange rate		(16,543)	15,986
Balance at end of the year		1,761,558	2,538,049
Less: current		(708,268)	(1,507,564)
Noncurrent		1,053,290	1,030,485
Warranties [member]
Disclosure of movements in provisions [Line Items]
Balance at beginning of the year	[1]	1,463,869	1,546,960
Additions	[1]	554,935	276,846
Usage	[1]	(422,976)	(259,109)
Reversals	[1]	(303,423)	(100,754)
Effect of change in exchange rate	[1]	(159)	(74)
Balance at end of the year	[1]	1,292,246	1,463,869
Less: current	[1]	(486,517)	(686,424)
Noncurrent	[1]	805,729	777,445
Litigation and claims [member]
Disclosure of movements in provisions [Line Items]
Balance at beginning of the year		431,228	89,520
Additions			336,061
Usage		(156,521)
Reversals		(116,094)
Effect of change in exchange rate		(6,312)	5,647
Balance at end of the year		152,301	431,228
Less: current		(152,301)	(431,228)
Others [member]
Disclosure of movements in provisions [Line Items]
Balance at beginning of the year		642,952	249,483
Additions		11,800	571,113
Usage		(63,661)	(187,842)
Reversals		(264,008)	(215)
Effect of change in exchange rate		(10,072)	10,413
Balance at end of the year		317,011	642,952
Less: current		(69,450)	(389,912)
Noncurrent		$ 247,561	$ 253,040
[1]	The provisions for warranties were estimated based on historical experience of warranty claims rate associated with similar products and services. The Company expects most warranty claims will be made within two years from the date of the sale of the product.

Operating Leases - Schedule of

Operating Leases - Schedule of Future Maturities of Operating Lease Payments (Detail) - TWD ($) $ in Thousands	Jan. 01, 2019	Dec. 31, 2018
Disclosure of non-cancellable lease payables [line items]
Minimum lease payments under non-cancellable operating lease	$ 5,942,211	$ 5,942,211
Less than one year [member]
Disclosure of non-cancellable lease payables [line items]
Minimum lease payments under non-cancellable operating lease		927,351
Between one and five years [member]
Disclosure of non-cancellable lease payables [line items]
Minimum lease payments under non-cancellable operating lease		2,928,983
More than five years [member]
Disclosure of non-cancellable lease payables [line items]
Minimum lease payments under non-cancellable operating lease		$ 2,085,877

Operating Leases - Additional I

Operating Leases - Additional Information (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Disclosure of operating leases [Line Items]
Operating lease rent expense	$ 1,064,263	$ 1,081,731
Repairs and maintenance expense, recognized by the lessor	$ 1,723	$ 18,396
Hsinchu Science Park Administration Bureau [Member]
Disclosure of operating leases [Line Items]
Operating leasing arrangements	20 years

Operating Leases - Schedule o_2

Operating Leases - Schedule of Future Maturities of Operating Lease Receivable (Detail) $ in Thousands	Dec. 31, 2018TWD ($)
Disclosure of non-cancellable lease receivables [line Items]
Minimum lease receivable under non-cancellable operating lease	$ 2,717,666
Less than one year [member]
Disclosure of non-cancellable lease receivables [line Items]
Minimum lease receivable under non-cancellable operating lease	105,788
Between one and five years [member]
Disclosure of non-cancellable lease receivables [line Items]
Minimum lease receivable under non-cancellable operating lease	423,150
More than five years [member]
Disclosure of non-cancellable lease receivables [line Items]
Minimum lease receivable under non-cancellable operating lease	$ 2,188,728

Employee Benefits - Schedule of

Employee Benefits - Schedule of Net Defined Benefit Liability (Detail) - Defined benefit plans [member] - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Disclosure of reconciliation for net defined benefit liability and its components [line items]
Present value of defined benefit obligation	$ (3,155,988)	$ (3,257,962)
Fair value of plan assets	2,542,831	2,367,273
Net defined benefit liability	$ (613,157)	$ (890,689)

Employee Benefits - Schedule _2

Employee Benefits - Schedule of Reconciliation for Net Defined Benefit Asset (Liability) and Its Components (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Defined benefit obligation [member]
Disclosure of reconciliation for net defined benefit asset (liability) and its components [line items]
Balance at beginning	$ (3,257,962)	$ (3,128,927)
Included in profit or loss
Service cost	(4,104)	(5,289)
Interest cost	(39,337)	(49,598)
Expected return on plan assets	0	0
Subtotal in profit or loss	(43,441)	(54,887)
Included in other comprehensive income
Actuarial (loss) gain arising from demographic assumptions	89,851	(15,795)
Actuarial (loss) gain arising from financial assumptions	(206,995)	(178,212)
Actuarial (loss) gain arising from experience adjustment	228,466	84,437
Return on plan assets excluding interest income	0	0
Subtotal in other comprehensive income	111,322	(109,570)
Other changes
Contributions paid by the employer	0	0
Benefits paid	33,936	36,915
Effect of changes in exchange rates and others	157	(1,493)
Subtotal of other changes	34,093	35,422
Balance at ending	(3,155,988)	(3,257,962)
Fair value of plan assets [member]
Disclosure of reconciliation for net defined benefit asset (liability) and its components [line items]
Balance at beginning	2,367,273	2,213,018
Included in profit or loss
Service cost	0	0
Interest cost	0	0
Expected return on plan assets	28,880	35,408
Subtotal in profit or loss	28,880	35,408
Included in other comprehensive income
Actuarial (loss) gain arising from demographic assumptions	0	0
Actuarial (loss) gain arising from financial assumptions	0	0
Actuarial (loss) gain arising from experience adjustment	0	0
Return on plan assets excluding interest income	76,788	52,614
Subtotal in other comprehensive income	76,788	52,614
Other changes
Contributions paid by the employer	101,019	102,831
Benefits paid	(31,129)	(36,598)
Effect of changes in exchange rates and others	0	0
Subtotal of other changes	69,890	66,233
Balance at ending	2,542,831	2,367,273
Net defined benefit asset (liability) [Member]
Disclosure of reconciliation for net defined benefit asset (liability) and its components [line items]
Balance at beginning	(890,689)	(915,909)
Included in profit or loss
Service cost	(4,104)	(5,289)
Interest cost	(39,337)	(49,598)
Expected return on plan assets	28,880	35,408
Subtotal in profit or loss	(14,561)	(19,479)
Included in other comprehensive income
Actuarial (loss) gain arising from demographic assumptions	89,851	(15,795)
Actuarial (loss) gain arising from financial assumptions	(206,995)	(178,212)
Actuarial (loss) gain arising from experience adjustment	228,466	84,437
Return on plan assets excluding interest income	76,788	52,614
Subtotal in other comprehensive income	188,110	(56,956)
Other changes
Contributions paid by the employer	101,019	102,831
Benefits paid	2,807	317
Effect of changes in exchange rates and others	157	(1,493)
Subtotal of other changes	103,983	101,655
Balance at ending	$ (613,157)	$ (890,689)

Employee Benefits - Additional

Employee Benefits - Additional Information (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Employee Benefits Explanatory [Line Items]
Assets of benefit plan	$ 2,542,854
Estimate of contributions expected to be paid to plan for next annual reporting period	100,799
Employee benefits expense	38,154,140	$ 42,751,122	$ 44,900,469
Domestic defined contribution plans [member]
Disclosure Of Employee Benefits Explanatory [Line Items]
Employee benefits expense	977,908	1,024,700	1,003,063
Overseas defined contribution plans [Member]
Disclosure Of Employee Benefits Explanatory [Line Items]
Employee benefits expense	$ 784,169	$ 923,378	$ 892,109
Bottom of range [member]
Disclosure Of Employee Benefits Explanatory [Line Items]
Weighted-average duration of defined benefit obligation	5 years
Top of range [member]
Disclosure Of Employee Benefits Explanatory [Line Items]
Weighted-average duration of defined benefit obligation	20 years

Employee Benefits - Schedule _3

Employee Benefits - Schedule of Principal Actuarial Assumptions Used (Detail)	Dec. 31, 2019	Dec. 31, 2018
Bottom of range [member]
Disclosure of principal actuarial assumptions [Line Items]
Discount rate	0.18%	0.21%
Rate of increase in future salary	0.77%	0.77%
Top of range [member]
Disclosure of principal actuarial assumptions [Line Items]
Discount rate	0.88%	1.22%
Rate of increase in future salary	4.49%	4.49%

Employee Benefits - Disclosure

Employee Benefits - Disclosure of Additional Information About Defined Benefit Plans (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Actuarial assumption of discount rates [member]
Disclosure of affected defined benefit obligation amount with changes in assumptions [Line Items]
Increase (decrease) in defined benefit obligation due to 0.25% increase in actuarial assumption	$ (150,970)	$ (160,307)
Increase (decrease) in defined benefit obligation due to 0.25% decrease in actuarial assumption	159,425	169,544
Actuarial assumption of expected rates of salary increases [member]
Disclosure of affected defined benefit obligation amount with changes in assumptions [Line Items]
Increase (decrease) in defined benefit obligation due to 0.25% increase in actuarial assumption	156,774	166,250
Increase (decrease) in defined benefit obligation due to 0.25% decrease in actuarial assumption	$ (148,385)	$ (158,100)

Capital and Other Components _3

Capital and Other Components of Equity - Additional Information (Detail) - TWD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disclosure Of Capital And Other Components Of Equity [Line Items]
Par value per share	$ 10	$ 10
Authorized capital	$ 100,000,000	$ 100,000,000
Issued capital	$ 96,242,451	$ 96,242,451
Capital Surplus Capitalized Rate	10.00%
Legal Reserve Distribution Description	According to the ROC Company Act, 10 percent of the net profit shall be allocated as legal reserve until the accumulated legal reserve equals the paid-in capital. When a company incurs no loss, it may, pursuant to a resolution to be adopted by shareholders’ meeting, distribute its legal reserve by issuing new shares or by cash, only the portion of legal reserve which exceeds 25 percent of the paid-in capital may be distributed.
Description of distribution of earnings and dividend policy	If the current-year retained earnings available for distribution reach 2% of the paid-in capital of AUO, dividend to be distributed shall be no less than 20% of the current-year retained earnings available for distribution. If the current-year retained earnings available for distribution do not reach 2% of the paid-in capital of AUO, AUO may decide not to distribute dividend. The cash portion of the dividend, which may be in the form of cash and stock, shall not be less than 10% of the total dividend distributed during the year.
Expected shares repurchased as treasury shares transferring to employees	125,000
Maximum percentage of number of shares repurchased pursuant to the Securities and Exchange Act	10.00%
Share repurchased transferring period from the date of reaquisition	5 years
American Depositary Shares (one represents ten common shares) [member]
Disclosure Of Capital And Other Components Of Equity [Line Items]
Number of shares issued	50,123
Number of ordinary shares represented	501,229

Capital and Other Components _4

Capital and Other Components of Equity - Schedule of Components of Capital Surplus (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Disclosure of balance of capital surplus [line items]
Capital surplus	$ 60,543,683	$ 60,620,224
From convertible bonds
Disclosure of balance of capital surplus [line items]
Capital surplus	6,049,862	6,049,862
From others
Disclosure of balance of capital surplus [line items]
Capital surplus	1,737,730	1,814,271
From common stock
Disclosure of balance of capital surplus [line items]
Capital surplus	$ 52,756,091	$ 52,756,091

Capital and Other Components _5

Capital and Other Components of Equity - Summary of Appropriations and Dividend Per Share (Detail) - TWD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Disclosure of distribution of earnings [abstract]
Legal reserve	$ 1,016,060	$ 3,235,942
Special reserve	847,770
Cash dividends to shareholders	$ 4,812,122	$ 14,436,368
Cash dividends to shareholders, per share	$ 0.50	$ 1.50
Appropriation Of Earnings	$ 6,675,952	$ 17,672,310

Capital and Other Components _6

Capital and Other Components of Equity - Schedule Of Related Information On treasury Share Transactions (Detail) - Transfer to employees [member] shares in Thousands	12 Months Ended
	Dec. 31, 2019shares
Disclosure of treasury share transactions
Number of shares, Beginning of Period	0
Addition	125,000
Reductions	0
Number of shares, End of Period	125,000

Capital and Other Components _7

Capital and Other Components of Equity - Summary of Other Components of Equity (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of other components of equity [Line Items]
Group reorganization		$ 0
Related tax	$ (459,729)	(191,809)	$ (316,372)
AOCI Attributable to Parent [Member]
Disclosure of other components of equity [Line Items]
Balance beginning	(847,770)	256,062	777,297
Adjustments on initial application of new standards		(73,215)
Foreign operations - foreign currency translation differences	(2,043,931)	(336,902)	(1,882,545)
Net change in fair value of financial assets at FVTOCI	519,100	(754,813)
Effective portion of changes in fair value of cash flow hedges			(21,992)
Net change in fair value of available-for-sale financial assets			1,146,422
Equity-accounted investees - share of other comprehensive income	(35,154)	(16,663)	(62,327)
Realized gain on sales of securities reclassified to profit or loss	(9,098)	(107,457)
Cumulative unrealized loss of equity instruments transferred to retained earnings due to disposal		50,084
Group reorganization		(22,225)
Related tax	411,469	157,359	299,207
Balance ending	(2,005,384)	(847,770)	256,062
Cumulative translation differences | AOCI Attributable to Parent [Member]
Disclosure of other components of equity [Line Items]
Balance beginning	(1,449,910)	(1,120,969)	531,006
Adjustments on initial application of new standards		0
Foreign operations - foreign currency translation differences	(2,043,931)	(336,902)	(1,882,545)
Net change in fair value of financial assets at FVTOCI	0	0
Effective portion of changes in fair value of cash flow hedges			0
Net change in fair value of available-for-sale financial assets			0
Equity-accounted investees - share of other comprehensive income	(38,512)	(19,716)	(68,637)
Realized gain on sales of securities reclassified to profit or loss	(9,098)	(107,457)
Cumulative unrealized loss of equity instruments transferred to retained earnings due to disposal		0
Group reorganization		(22,225)
Related tax	411,469	157,359	299,207
Balance ending	(3,129,982)	(1,449,910)	(1,120,969)
Unrealized gains (losses) on available-for-sale financial assets [member]
Disclosure of other components of equity [Line Items]
Group reorganization		0
Unrealized gains (losses) on available-for-sale financial assets [member] | AOCI Attributable to Parent [Member]
Disclosure of other components of equity [Line Items]
Balance beginning	0	1,377,031	224,299
Adjustments on initial application of new standards		(1,377,031)
Foreign operations - foreign currency translation differences		0	0
Net change in fair value of financial assets at FVTOCI		0
Effective portion of changes in fair value of cash flow hedges			0
Net change in fair value of available-for-sale financial assets			1,146,422
Equity-accounted investees - share of other comprehensive income		0	6,310
Realized gain on sales of securities reclassified to profit or loss		0
Cumulative unrealized loss of equity instruments transferred to retained earnings due to disposal		0
Group reorganization		0
Related tax		0	0
Balance ending		0	1,377,031
Unrealized gains (losses) on cash flow hedges [member]
Disclosure of other components of equity [Line Items]
Group reorganization		0
Unrealized gains (losses) on cash flow hedges [member] | AOCI Attributable to Parent [Member]
Disclosure of other components of equity [Line Items]
Balance beginning		0	21,992
Foreign operations - foreign currency translation differences			0
Effective portion of changes in fair value of cash flow hedges			(21,992)
Net change in fair value of available-for-sale financial assets			0
Equity-accounted investees - share of other comprehensive income			0
Related tax			0
Balance ending			0
Unrealized gains (losses) on financial assets at FVTOCI | AOCI Attributable to Parent [Member]
Disclosure of other components of equity [Line Items]
Balance beginning	602,140	0
Adjustments on initial application of new standards		1,303,816
Foreign operations - foreign currency translation differences	0	0
Net change in fair value of financial assets at FVTOCI	519,100	(754,813)
Equity-accounted investees - share of other comprehensive income	3,358	3,053
Realized gain on sales of securities reclassified to profit or loss	0	0
Cumulative unrealized loss of equity instruments transferred to retained earnings due to disposal		50,084
Group reorganization		0
Related tax	0	0
Balance ending	$ 1,124,598	$ 602,140	$ 0

Capital and Other Components _8

Capital and Other Components of Equity - Schedule of Non-Controlling Interest, Net of Tax (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of Non-controlling interests net of tax [abstract]
Balance at the beginning of the year	$ 14,416,559	$ 17,068,501	$ 18,388,204
Equity attributable to non-controlling interests:
Loss for the year	(2,413,718)	(2,177,869)	(2,120,737)
Adjustment of changes in ownership of investees	110,028	(20,998)	(6,421)
Foreign currency translation differences	(404,575)	(306,963)	(355,700)
Unrealized losses on financial assets at FVTOCI	0	(1,474)	0
Remeasurement of defined benefit plans	0	0	201
Effect of disposal of interest in subsidiary to non-controlling interests	0	0	1,258,788
Effect of acquisition of non-controlling interests	(389,430)	0	0
Proceeds from subsidiaries capital increase and others	(13,957)	(144,638)	(95,834)
Balance at the end of the year	$ 11,304,907	$ 14,416,559	$ 17,068,501

Share-based Payments - Schedule

Share-based Payments - Schedule of Number and Weighted Average Exercise Prices of DPTW Option Plan (Detail) - Employee Stock Option Plan 2011 [member] - DPTW Option Plan [Member]	12 Months Ended
	Dec. 31, 2017shares$ / shares
Disclosure of outstanding stock options [Line Items]
Weighted-average exercise price (per share), Outstanding Beggining balance | $ / shares	$ 19.04
Weighted average exercise price (per share), Options expired | $ / shares	0
Weighted-average exercise price (per share), Outstanding Ending Balance | $ / shares	$ 0
Number of options, Outstanding Beggining balance	2,913,000
Number of options, Options expired	(2,913,000)
Number of options, Outstanding at Ending balance	0
Number of options, Exercisable at Ending balance	0

Share-based Payments - Schedu_2

Share-based Payments - Schedule of Terms and Conditions of ACTW Option Plan (Detail) - Employee Stock Option Plan 2014 [Member] - ACTW Option Plan [Member] Number in Thousands	12 Months Ended
	Dec. 31, 2018Number$ / shares
Disclosure of terms and conditions relating to employee stock option plan [Line Items]
Grant date	Sep. 1, 2014
Total number of options issued (units) | Number	20
Contractual life of options	Sep.1, 2014 - Aug. 31, 2019
Exercisable period	After Aug. 31, 2016
Exercise price (per share) | $ / shares	$ 10

Share-based Payments - Addition

Share-based Payments - Additional Information (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
ACTW Option Plan [Member]
Disclosure of Share-based Payments [Line Items]
Expense from share-based payment transactions with employees	$ 0	$ 167	$ 474

Share-based Payments - Schedu_3

Share-based Payments - Schedule of Valuation Information of ACTW Option Plan (Detail) - Employee Stock Option Plan 2014 [Member] - ACTW Option Plan [Member]	12 Months Ended
	Dec. 31, 2019TWD ($)yr
Disclosure of valuation information [Line Items]
Expected volatility	38.88%
Risk-free interest rate	1.1648%
Expected duration (in years) | yr	5
Fair value at the grant date (per share) | $	$ 0.20

Share-based Payments - Schedu_4

Share-based Payments - Schedule of Number and Weighted Average Exercise Prices of ACTW Option Plan (Detail) - ACTW Option Plan [Member] - Employee Stock Option Plan 2014 [Member]	12 Months Ended
	Dec. 31, 2019shares$ / shares	Dec. 31, 2018shares$ / shares
Disclosure of outstanding stock options [Line Items]
Weighted-average exercise price (per share), Outstanding Beggining balance | $ / shares	$ 10	$ 10
Weighted average exercise price (per share), Options exercised | $ / shares	10	10
Weighted average exercise price (per share), Options expired | $ / shares	0	0
Weighted-average exercise price (per share), Outstanding Ending Balance | $ / shares	$ 0	$ 10
Number of options, Outstanding Beggining balance	13,291,000	16,601,000
Number of options, Options exercised	(11,995,000)	(2,260,000)
Number of options, Options expired	(1,296,000)	(1,050,000)
Number of options, Outstanding at Ending balance	0	13,291,000
Number of options, Exercisable at Ending balance	0	13,291,000

Revenue from Contracts with C_3

Revenue from Contracts with Customers - Schedule of Revenue from Contracts with Customers on Primary Geographical Markets (Detail) - Revenue From Primary Geographical Market [Member] - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	$ 268,791,694	$ 307,634,389
PRC [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	98,362,235	113,632,037
Taiwan ROC [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	83,229,594	99,357,882
Singapore [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	38,534,291	39,370,930
Japan [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	20,924,003	21,166,864
Others [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	27,741,571	34,106,676
Dispaly segment [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	256,667,222	290,784,754
Dispaly segment [Member] | PRC [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	97,084,436	112,542,529
Dispaly segment [Member] | Taiwan ROC [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	78,394,325	93,126,115
Dispaly segment [Member] | Singapore [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	38,526,625	39,363,415
Dispaly segment [Member] | Japan [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	19,877,671	19,748,373
Dispaly segment [Member] | Others [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	22,784,165	26,004,322
Energy segment [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	12,124,472	16,849,635
Energy segment [Member] | PRC [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	1,277,799	1,089,508
Energy segment [Member] | Taiwan ROC [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	4,835,269	6,231,767
Energy segment [Member] | Singapore [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	7,666	7,515
Energy segment [Member] | Japan [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	1,046,332	1,418,491
Energy segment [Member] | Others [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	$ 4,957,406	$ 8,102,354

Revenue from Contracts with C_4

Revenue from Contracts with Customers - Schedule of Revenue from Contracts with Customers on Major Products (Detail) - Revenue From Major Products And Services [Member] - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers		$ 268,791,694	$ 307,634,389
Products for Televisions [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers		87,269,763	113,194,567
Products For Mobile PCs And Devices [member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers		69,305,510	74,375,305
Products for Monitors [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers		39,522,268	47,024,353
Products for Commercial and Others [member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	[1]	60,569,681	56,190,529
Solar Products [member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers		12,124,472	16,849,635
Dispaly segment [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers		256,667,222	290,784,754
Dispaly segment [Member] | Products for Televisions [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers		87,269,763	113,194,567
Dispaly segment [Member] | Products For Mobile PCs And Devices [member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers		69,305,510	74,375,305
Dispaly segment [Member] | Products for Monitors [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers		39,522,268	47,024,353
Dispaly segment [Member] | Products for Commercial and Others [member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	[1]	60,569,681	56,190,529
Energy segment [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers		12,124,472	16,849,635
Energy segment [Member] | Solar Products [member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers		$ 12,124,472	$ 16,849,635
[1]	Others include sales from products for other applications and sales of raw materials, components and from service charges.

Revenue from Contracts with C_5

Revenue from Contracts with Customers - Schedule of Revenue from Contracts on Major Customers (Detail) - Revenue From Major Customers [Member] - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	$ 268,791,694	$ 307,634,389
Customer A [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	33,142,985	35,358,013
Other Customers [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	235,648,709	272,276,376
Dispaly segment [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	256,667,222	290,784,754
Dispaly segment [Member] | Customer A [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	33,142,985	35,358,013
Dispaly segment [Member] | Other Customers [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	223,524,237	255,426,741
Energy segment [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	12,124,472	16,849,635
Energy segment [Member] | Other Customers [Member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Revenue from contracts with customers	$ 12,124,472	$ 16,849,635

Revenue - Schedule of Component

Revenue - Schedule of Components of Revenue (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure - Revenue - Schedule of Components of Revenue [Abstract]
Sale of goods			$ 329,584,136
Other operating revenue			11,444,131
Revenue	$ 268,791,694	$ 307,634,389	$ 341,028,267

Remuneration to Employees and_2

Remuneration to Employees and Directors - Additional Information (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of Remuneration to Employees and Directors [Abstract]
Employees' minimum remuneration percentage	5.00%
Directors' maximum remuneration percentage	1.00%
Other short-term employee benefits		$ 1,215,696	$ 4,062,114
Directors' remuneration expense		$ 27,780	$ 132,604

The Nature of Expenses - Schedu

The Nature of Expenses - Schedule of Depreciation of Property, Plant and Equipment (Detail) - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Expenses By Nature Explanatory [line items]
Depreciation expense		$ 35,693,033	$ 33,686,561	$ 35,801,230
Cost Of Sales [Member]
Disclosure Of Expenses By Nature Explanatory [line items]
Depreciation expense		31,599,910	29,980,415	31,660,279
Operating Expenses [Member]
Disclosure Of Expenses By Nature Explanatory [line items]
Depreciation expense	[1]	$ 4,093,123	$ 3,706,146	$ 4,140,951
[1]	(i) Operating expenses are inclusive of selling and distribution expenses, general and administrative expenses and research and development expenses.

The Nature of Expenses - Sche_2

The Nature of Expenses - Schedule of Amortization of Intangible Assets (Detail) - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Expenses By Nature Explanatory [line items]
Amortization expense		$ 564,686	$ 540,969	$ 628,606
Cost Of Sales [Member]
Disclosure Of Expenses By Nature Explanatory [line items]
Amortization expense		436,815	518,403	628,606
Operating Expenses [Member]
Disclosure Of Expenses By Nature Explanatory [line items]
Amortization expense	[1]	$ 127,871	$ 22,566	$ 0
[1]	(i) Operating expenses are inclusive of selling and distribution expenses, general and administrative expenses and research and development expenses.

The Nature of Expenses - Sche_3

The Nature of Expenses - Schedule of Employee Benefits Expenses (Detail) - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Detailed Information Of Employees Benefits Expenses [line items]
Salaries and wages		$ 30,824,887	$ 34,933,925	$ 37,818,321
Labor and health insurances		1,917,244	2,009,652	1,967,688
Retirement benefits		1,776,638	1,967,557	1,917,136
Other employee benefits		3,635,371	3,839,988	3,197,324
Employee benefits expense		38,154,140	42,751,122	44,900,469
Cost Of Sales [Member]
Disclosure Of Detailed Information Of Employees Benefits Expenses [line items]
Employee benefits expense		29,453,257	33,455,273	34,703,579
Operating Expenses [Member]
Disclosure Of Detailed Information Of Employees Benefits Expenses [line items]
Employee benefits expense	[1]	$ 8,700,883	$ 9,295,849	$ 10,196,890
[1]	(i) Operating expenses are inclusive of selling and distribution expenses, general and administrative expenses and research and development expenses.

Other Income - Schedule of Othe

Other Income - Schedule of Other Income (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of other income explanatory [Abstract]
Interest income on bank deposits	$ 879,053	$ 832,621	$ 591,995
Interest income on government bonds with reverse repurchase agreements and others	6,467	8,994	20,215
Rental income, net	488,811	628,401	531,442
Dividend income	295,575	468,263	248,514
Grants	2,734,987	2,716,197	1,801,585
Others	915,378	757,649	636,146
Other income	$ 5,320,271	$ 5,412,125	$ 3,829,897

Other Gains and Losses - Schedu

Other Gains and Losses - Schedule of Other Gains and Losses (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of other gains and losses [Abstract]
Foreign exchange gains (losses), net	$ (168,499)	$ (41,391)	$ (1,364,929)
Gains on valuation of financial instruments at FVTPL, net	381,620	507,532	1,646,034
Gains (losses) on disposals of investments and financial assets, net	(13,154)	0	42,788
Gains on disposals of property, plant and equipment, net	106,546	1,923,044	330,814
Impairment losses on assets	(2,298,646)	(399,363)	(1,046,668)
Gains (losses) from litigation and others	396,519	(501,770)	(584,599)
Other gains (losses)	$ (1,595,614)	$ 1,488,052	$ (976,560)

Finance Costs - Schedule of Bor

Finance Costs - Schedule of Borrowing Costs (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of finance cost explanatory [Abstract]
Interest expense on bank borrowings	$ 2,714,080	$ 2,442,872	$ 2,519,839
Interest expense on lease liabilities	209,607	0	0
Interest expense on others	327,683	220,733	348,022
Finance costs	$ 3,251,370	$ 2,663,605	$ 2,867,861

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of income tax explanatory [line items]
Applicable tax rate	20.00%	20.00%	17.00%
Tax benefit arising from previously unrecognised tax loss, tax credit or temporary difference of prior period used to reduce deferred tax expense	$ (682,930)	$ (1,998,662)	$ 3,819,489
Temporary differences associated with investments in subsidiaries, branches and associates and interests in joint arrangements for which deferred tax liabilities have not been recognised	$ 277,670
Undistributed Earnings [Member]
Disclosure of income tax explanatory [line items]
Applicable tax rate	5.00%	5.00%	10.00%
Deferred tax assets [member]
Disclosure of income tax explanatory [line items]
Utilization Of Previously Unrecognized Tax Losses			$ 7,494,191
Tax benefit arising from previously unrecognised tax loss, tax credit or temporary difference of prior period used to reduce deferred tax expense			$ 3,878,233
U-Fresh Technology Inc. (UTI) [Member]
Disclosure of income tax explanatory [line items]
Unused tax credits for which no deferred tax asset recognised	$ 154
AFPD Pte., Ltd (AUST) [Member]
Disclosure of income tax explanatory [line items]
Unused tax credits for which no deferred tax asset recognised	974,909
AUO Crystal (Malaysia) Sdn. Bhd. (ACMK) [Member]
Disclosure of income tax explanatory [line items]
Unused tax credits for which no deferred tax asset recognised	$ 6,297

Income Taxes - Schedule of Comp

Income Taxes - Schedule of Components of Income Tax Expense (Benefit) (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current income tax expense (benefit):
Current year	$ 752,863	$ 1,444,698	$ 3,719,483
Adjustment to prior years and others	(684,197)	(1,772,898)	246,264
Current income tax expense (benefit)	68,666	(328,200)	3,965,747
Deferred tax expense (benefit):
Temporary differences	584,559	(632,785)	(1,271,415)
Investment tax credit and tax losses carryforwards	682,930	1,998,662	(3,819,489)
Effect of changes in statutory income tax rate	0	(715,303)	0
Deferred tax expense (benefit)	1,267,489	650,574	(5,090,904)
Income tax expense (benefit)	$ 1,336,155	$ 322,374	$ (1,125,157)

Income Taxes - Schedule of Info

Income Taxes - Schedule of Information about Income Taxes Expense Benefit Recognized Directly in Other Comprehensive Income (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Items that will never be reclassified to profit or loss:
Remeasurement of defined benefit obligations	$ 37,622	$ (38,908)	$ (155,930)
Items that are or may be reclassified subsequently to profit or loss:
Foreign operations - foreign currency translation differences	$ (459,729)	$ (191,809)	$ (316,372)

Income Taxes - Schedule of Inco

Income Taxes - Schedule of Income Tax Reconciliation (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of accounting profit multiplied by applicable tax rates [abstract]
Profit (Loss) before income taxes	$ (19,844,754)	$ 11,216,151	$ 39,363,606
Income tax expense at AUO's statutory tax rate	(3,968,951)	2,243,230	6,691,813
Effect of different subsidiaries income tax rate	38,756	(484,055)	348,192
Share of profit (loss) of equity-accounted subsidiaries	(73,968)	795,459	(708,417)
Effect of changes in statutory income tax rate	0	(715,303)	0
Effect of change of unrecognized deductible temporary differences, tax losses carryforwards, and investment tax credits	5,947,778	138,969	(10,645,339)
Net of non-taxable income and non-deductible expense	265,119	(186,957)	698,540
Tax on undistributed earnings, net	7,709	323,559	2,987,763
Adjustments to prior year	(684,197)	(1,772,898)	(528,662)
Others	(196,091)	(19,630)	30,953
Income tax expense (benefit)	$ 1,336,155	$ 322,374	$ (1,125,157)
Effective tax rate	(6.73%)	2.87%	(2.85%)

Income Taxes - Schedule of Defe

Income Taxes - Schedule of Deferred Taxes and Liabilities (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of income tax explanatory [line items]
Investment tax credits	$ 385,728	$ 542,115
Tax losses carryforwards	2,223,440	2,760,163
Unrealized loss and expenses	161,072	304,636
Inventories write-down	879,267	1,027,680
Foreign investment gains under the equity method	(1,043,486)	(1,049,091)
Remeasurement of defined benefit plans	157,216	194,838
Foreign operations - foreign currency translation differences	886,062	426,333
Others	481,647	793,830
Deferred tax assets (liabilities)	4,130,946	5,000,504	$ 5,430,787
Deferred tax assets [Member]
Disclosure of income tax explanatory [line items]
Investment tax credits	385,728	542,115
Tax losses carryforwards	2,223,440	2,760,163
Unrealized loss and expenses	166,393	310,192
Inventories write-down	879,267	1,027,680
Foreign investment gains under the equity method	0	0
Remeasurement of defined benefit plans	157,216	194,838
Foreign operations - foreign currency translation differences	886,062	426,333
Others	483,511	1,371,347
Deferred tax assets (liabilities)	5,181,617	6,632,668
Deferred tax liabilities [Member]
Disclosure of income tax explanatory [line items]
Investment tax credits	0	0
Tax losses carryforwards	0	0
Unrealized loss and expenses	(5,321)	(5,556)
Inventories write-down	0	0
Foreign investment gains under the equity method	(1,043,486)	(1,049,091)
Remeasurement of defined benefit plans	0	0
Foreign operations - foreign currency translation differences	0	0
Others	(1,864)	(577,517)
Deferred tax assets (liabilities)	$ (1,050,671)	$ (1,632,164)

Income Taxes - Schedule of Chan

Income Taxes - Schedule of Changes in Deferred Tax Assets and Liabilities (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets and liabilities [abstract]
Balance Beginning	$ 5,000,504	$ 5,430,787
Recognized in profit or loss	(1,267,489)	(650,574)	$ 5,090,904
Recognized in other comprehensive income	422,107	230,717
Effect of change in consolidated entities, exchange rate and others	(24,176)	(10,426)
Balance Ending	4,130,946	5,000,504	5,430,787
Investment tax credits [Member]
Deferred tax assets and liabilities [abstract]
Balance Beginning	542,115	656,480
Recognized in profit or loss	(148,453)	(132,840)
Recognized in other comprehensive income	0	0
Effect of change in consolidated entities, exchange rate and others	(7,934)	18,475
Balance Ending	385,728	542,115	656,480
Tax losses carryforwards [Member]
Deferred tax assets and liabilities [abstract]
Balance Beginning	2,760,163	3,942,012
Recognized in profit or loss	(534,477)	(1,181,429)
Recognized in other comprehensive income	0	0
Effect of change in consolidated entities, exchange rate and others	(2,246)	(420)
Balance Ending	2,223,440	2,760,163	3,942,012
Unrealized loss and expenses [Member]
Deferred tax assets and liabilities [abstract]
Balance Beginning	304,636	222,739
Recognized in profit or loss	(143,534)	81,893
Recognized in other comprehensive income	0	0
Effect of change in consolidated entities, exchange rate and others	(30)	4
Balance Ending	161,072	304,636	222,739
Inventories write-down [Member]
Deferred tax assets and liabilities [abstract]
Balance Beginning	1,027,680	644,887
Recognized in profit or loss	(148,035)	386,558
Recognized in other comprehensive income	0	0
Effect of change in consolidated entities, exchange rate and others	(378)	(3,765)
Balance Ending	879,267	1,027,680	644,887
Foreign investment losses (gains) under the equity method [Member]
Deferred tax assets and liabilities [abstract]
Balance Beginning	(1,049,091)	(890,153)
Recognized in profit or loss	5,605	(158,938)
Recognized in other comprehensive income	0	0
Effect of change in consolidated entities, exchange rate and others	0	0
Balance Ending	(1,043,486)	(1,049,091)	(890,153)
Remeasurement of defined benefit plans [Member]
Deferred tax assets and liabilities [abstract]
Balance Beginning	194,838	155,930
Recognized in profit or loss	0	0
Recognized in other comprehensive income	(37,622)	38,908
Effect of change in consolidated entities, exchange rate and others	0	0
Balance Ending	157,216	194,838	155,930
Foreign operations-foreign currency translation differences [Member]
Deferred tax assets and liabilities [abstract]
Balance Beginning	426,333	234,524
Recognized in profit or loss	0	0
Recognized in other comprehensive income	459,729	191,809
Effect of change in consolidated entities, exchange rate and others	0	0
Balance Ending	886,062	426,333	234,524
Others [Member]
Deferred tax assets and liabilities [abstract]
Balance Beginning	793,830	464,368
Recognized in profit or loss	(298,595)	354,182
Recognized in other comprehensive income	0	0
Effect of change in consolidated entities, exchange rate and others	(13,588)	(24,720)
Balance Ending	$ 481,647	$ 793,830	$ 464,368

Income Taxes - Schedule of Unre

Income Taxes - Schedule of Unrecognized Deferred Tax Assets (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Disclosure of income tax explanatory [Abstract]
Unused tax losses carryforwards	$ 32,445,130	$ 28,697,671
Unused investment tax credits	981,360	853,837
Difference in depreciation expense for tax and financial purposes	1,866,430	1,972,536
Inventories write-down	22,875	19,852
Others	1,730,739	646,390
Total unrecognized deferred tax assets	$ 37,046,534	$ 32,190,286

Income Taxes - Schedule of In_2

Income Taxes - Schedule of Information About Unused Tax Losses Carryforwards (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disclosure of income tax explanatory [line items]
Unrecognized deferred tax assets relating to unused tax losses carryforwards	$ 32,445,130	$ 28,697,671
2011 Unused tax losses carryforwards [Member]
Disclosure of income tax explanatory [line items]
Unrecognized deferred tax assets relating to unused tax losses carryforwards	$ 2,904,785
Description of expiry date of deductible temporary differences, unused tax losses and unused tax credits	2020 ~ 2021
2012 Unused tax losses carryforwards [Member]
Disclosure of income tax explanatory [line items]
Unrecognized deferred tax assets relating to unused tax losses carryforwards	$ 11,042,933
Description of expiry date of deductible temporary differences, unused tax losses and unused tax credits	2021 ~ 2022
2013 Unused tax losses carryforwards [Member]
Disclosure of income tax explanatory [line items]
Unrecognized deferred tax assets relating to unused tax losses carryforwards	$ 1,747,050
Description of expiry date of deductible temporary differences, unused tax losses and unused tax credits	2022 ~ 2023
2014 Unused tax losses carryforwards [Member]
Disclosure of income tax explanatory [line items]
Unrecognized deferred tax assets relating to unused tax losses carryforwards	$ 2,347,376
Description of expiry date of deductible temporary differences, unused tax losses and unused tax credits	2023 ~ 2024
2015 Unused tax losses carryforwards [Member]
Disclosure of income tax explanatory [line items]
Unrecognized deferred tax assets relating to unused tax losses carryforwards	$ 2,159,621
Description of expiry date of deductible temporary differences, unused tax losses and unused tax credits	2020 ~ 2025
2016 Unused tax losses carryforwards [Member]
Disclosure of income tax explanatory [line items]
Unrecognized deferred tax assets relating to unused tax losses carryforwards	$ 4,259,267
Description of expiry date of deductible temporary differences, unused tax losses and unused tax credits	2020 ~ 2026
2017 Unused tax losses carryforwards [Member]
Disclosure of income tax explanatory [line items]
Unrecognized deferred tax assets relating to unused tax losses carryforwards	$ 2,314,089
Description of expiry date of deductible temporary differences, unused tax losses and unused tax credits	2021 ~ 2026
2018 Unused tax losses carryforwards [Member]
Disclosure of income tax explanatory [line items]
Unrecognized deferred tax assets relating to unused tax losses carryforwards	$ 1,279,958
Description of expiry date of deductible temporary differences, unused tax losses and unused tax credits	2023 ~ 2028
2019 estimated Unused tax losses carryforwards [Member]
Disclosure of income tax explanatory [line items]
Unrecognized deferred tax assets relating to unused tax losses carryforwards	$ 4,390,051
Description of expiry date of deductible temporary differences, unused tax losses and unused tax credits	2023 ~ 2029

Earnings (Loss) Per Share - Sch

Earnings (Loss) Per Share - Schedule of Basic Earnings Per Share (Detail) - TWD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of Earnings per Share [Abstract]
Profit (loss) attributable to AUO's shareholders	$ (18,767,191)	$ 13,071,646	$ 42,609,500
Weighted-average number of common shares outstanding during the year (basic)	9,597,268	9,624,245	9,624,245
Basic earnings (loss) per share	$ (1.96)	$ 1.36	$ 4.43

Earnings (Loss) Per Share - S_2

Earnings (Loss) Per Share - Schedule of Diluted Earnings Per Share (Detail) - TWD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of Earnings per Share [Abstract]
Profit (loss) attributable to AUO's shareholders	$ (18,767,191)	$ 13,071,646	$ 42,609,500
Weighted-average number of common shares outstanding during the year (including the effect of dilutive potential common stock):
Weighted-average number of common shares (basic)	9,597,268	9,624,245	9,624,245
Effect of employee remuneration in stock	0	164,609	347,903
Weighted-average number of common shares (diluted)	9,597,268	9,788,854	9,972,148
Diluted earnings (loss) per share (In dollars per share)	$ (1.96)	$ 1.34	$ 4.27

Cash Flow Information - Disclos

Cash Flow Information - Disclosure of Detailed Information About Reconciliation of Liabilities to Cash Flow Arising From Financing Activities (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of reconciliation of liabilities to cash flows arising from financing activities [Line Items]
Balance at Beginning	$ 87,668,302	$ 114,870,868	$ 125,627,606
Adjusted Balance at Beginning	100,357,828
Cash flows	26,992,734	(27,296,257)	(9,701,925)
Non-cash changes,Increase (decrease) in lease liabilities	(872,224)
Non-cash changes, Changes in exchange rate	(1,129,096)	(40,915)	(1,114,381)
Non-cash changes, Effect of change in consolidated entities			(84,187)
Non-cash changes, Amortization on transaction costs	221,285	134,606	143,755
Adjusted Balance at Ending	125,570,527	100,357,828
Balance at Ending		87,668,302	114,870,868
Long-term borrowings (including current installments) [Member]
Disclosure of reconciliation of liabilities to cash flows arising from financing activities [Line Items]
Balance at Beginning	86,305,318	110,608,010	124,262,620
Cash flows	26,501,234	(24,464,961)	(12,571,198)
Non-cash changes, Changes in exchange rate	(1,059,445)	27,663	(1,142,980)
Non-cash changes, Effect of change in consolidated entities			(84,187)
Non-cash changes, Amortization on transaction costs	221,285	134,606	143,755
Balance at Ending	111,968,392	86,305,318	110,608,010
Short-term borrowings [Member]
Disclosure of reconciliation of liabilities to cash flows arising from financing activities [Line Items]
Balance at Beginning	546,472	3,424,376	526,723
Cash flows	1,188,250	(2,817,894)	2,903,927
Non-cash changes, Changes in exchange rate	(9,120)	(60,010)	(6,274)
Balance at Ending	1,725,602	546,472	3,424,376
Guarantee deposits [member]
Disclosure of reconciliation of liabilities to cash flows arising from financing activities [Line Items]
Balance at Beginning	816,512	838,482	838,263
Cash flows	(1,828)	(13,402)	(34,654)
Non-cash changes, Changes in exchange rate	(29,228)	(8,568)	34,873
Balance at Ending	785,456	816,512	$ 838,482
Lease liabilities [member]
Disclosure of reconciliation of liabilities to cash flows arising from financing activities [Line Items]
Balance at Beginning	12,689,526
Cash flows	(694,922)
Non-cash changes,Increase (decrease) in lease liabilities	(872,224)
Non-cash changes, Changes in exchange rate	(31,303)
Balance at Ending	$ 11,091,077	$ 12,689,526

Financial Instruments - Schedul

Financial Instruments - Schedule of Other Financial Instruments at Carrying Amount and Fair Value (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financial liabilities held for trading [member]
Disclosure of detailed information about financial instruments [line items]
Financial liabilities, Fair Value	$ 18,859	$ 22,115
Financial lliabilities, Carrying Amount	18,859	22,115
Long-term borrowings [member]
Disclosure of detailed information about financial instruments [line items]
Financial liabilities, Fair Value	111,968,392	86,305,318
Financial lliabilities, Carrying Amount	111,968,392	86,305,318
Guarantee deposits [member]
Disclosure of detailed information about financial instruments [line items]
Financial liabilities, Fair Value	785,456	816,512
Financial lliabilities, Carrying Amount	785,456	816,512
Financial assets mandatorily Measured at Fair Value Through Profit or Loss [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets, Fair Value	1,521,406	1,709,531
Financial assets, Carrying Amount	1,521,406	1,709,531
Financial assets at fair value through other comprehensive income [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets, Fair Value	7,545,171	6,979,925
Financial assets, Carrying Amount	7,545,171	6,979,925
Long-term receivables [Member]
Disclosure of detailed information about financial instruments [line items]
Financial assets, Fair Value	5,812	930,001
Financial assets, Carrying Amount	5,812	930,001
Refundable deposits [Member]
Disclosure of detailed information about financial instruments [line items]
Financial assets, Fair Value	663,911	716,097
Financial assets, Carrying Amount	$ 663,911	$ 716,097

Financial Instruments - Sched_2

Financial Instruments - Schedule of Financial Assets and Liabilities at Fair Value on a Recurring Basis (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financial liabilities held for trading [member]
Disclosure of fair value measurements of assets and liabilities [line items]
Financial liabilities, at fair value	$ 18,859	$ 22,115
Long-term receivables [Member]
Disclosure of fair value measurements of assets and liabilities [line items]
Financial assets, at fair value	5,812	930,001
Financial assets mandatorily measured at fair value through profit or loss [member]
Disclosure of fair value measurements of assets and liabilities [line items]
Financial assets, at fair value	1,521,406	1,709,531
Financial assets at fair value through other comprehensive income [member]
Disclosure of fair value measurements of assets and liabilities [line items]
Financial assets, at fair value	7,545,171	6,979,925
Level 1 [member] | Financial assets at fair value through other comprehensive income [member]
Disclosure of fair value measurements of assets and liabilities [line items]
Financial assets, at fair value	7,356,501	6,803,900
Level 2 [member] | Financial liabilities held for trading [member]
Disclosure of fair value measurements of assets and liabilities [line items]
Financial liabilities, at fair value	18,859	22,115
Level 2 [member] | Long-term receivables [Member]
Disclosure of fair value measurements of assets and liabilities [line items]
Financial assets, at fair value	5,812	930,001
Level 2 [member] | Financial assets mandatorily measured at fair value through profit or loss [member]
Disclosure of fair value measurements of assets and liabilities [line items]
Financial assets, at fair value	1,521,406	1,709,531
Level 3 [member] | Financial assets at fair value through other comprehensive income [member]
Disclosure of fair value measurements of assets and liabilities [line items]
Financial assets, at fair value	$ 188,670	$ 176,025

Financial Instruments - Sched_3

Financial Instruments - Schedule of Changes in Level 3, Available for Sale Financial Assets without Quoted Market Prices (Detail) - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of detailed information about financial instruments [line items]
Total assets at the beginning of the year		$ 398,551,180
Total assets at the end of the year		$ 386,356,996	$ 398,551,180
Financial assets available-for-sale [member]
Disclosure of detailed information about financial instruments [line items]
Total assets at the beginning of the year			$ 177,815	$ 193,582
Net gains (losses) included in profit or loss	[1]			(30,000)
Purchases				14,233
Total assets at the end of the year				$ 177,815
[1]	Change in unrealized losses, which were included in profit or loss, relating to those available-for-sale assets without quoted market prices held at December 31, 2017 was $30,000 thousand.

Financial Instruments - Sched_4

Financial Instruments - Schedule of Changes in Level 3, Available for Sale Financial Assets without Quoted Market Prices (Parenthetical) (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2017TWD ($)
Disclosure of fair value measurement of assets [line items]
Gains (losses) recognised in profit or loss attributable to change in unrealised gains or losses for assets held at end of period, fair value measurement	$ (30,000)

Financial Instruments - Financi

Financial Instruments - Financial Instruments - Financial Assets at FVTOCI Equity Instruments Without Active Market (Detail) (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disclosure of detailed information about financial instruments [line items]
Total assets at the beginning of the year	$ 398,551,180
Total assets at the end of the year	386,356,996	$ 398,551,180
Financial assets at FVTOCI - equity instruments without active market [member]
Disclosure of detailed information about financial instruments [line items]
Total assets at the beginning of the year	176,025
Adjustments on initial application of IFRS 9		177,815
Net gains (losses) included in other comprehensive income	(33,501)	9,990
Purchases	47,182	34,157
Disposals		(45,937)
Effect of exchange rate change	(1,036)
Total assets at the end of the year	$ 188,670	$ 176,025

Financial Instruments - Sched_5

Financial Instruments - Schedule of Changes in Level 3 Valuation Processes and Quantitative Fair Value Measurement (Detail) - Financial assets at FVTOCI - equity instruments without active market [member]	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disclosure of detailed information about financial instruments [line items]
Valuation technique	Market approach
Discount for lack of marketability, significant unobservable inputs, assets		20.00%
Price Book Ratio [member]
Disclosure of detailed information about financial instruments [line items]
Inter-relationship between significant unobservable inputs and fair value measurement	The higher the price-book ratio is, the higher the fair value is.
Price Earnings Ratio [member]
Disclosure of detailed information about financial instruments [line items]
Inter-relationship between significant unobservable inputs and fair value measurement	The higher the price-earnings ratio is, the higher the fair value is.
Lack of Marketability [member]
Disclosure of detailed information about financial instruments [line items]
Inter-relationship between significant unobservable inputs and fair value measurement	The greater degree of lack of marketability is, the lower the fair value is.
Bottom of range [member]
Disclosure of detailed information about financial instruments [line items]
Price-Book ratio, significant unobservable inputs, assets	0.70	0.99
Price-Earnings ratio, significant unobservable inputs, assets	7.85	14.69
Discount for lack of marketability, significant unobservable inputs, assets	20.00%
Top of range [member]
Disclosure of detailed information about financial instruments [line items]
Price-Book ratio, significant unobservable inputs, assets	2.95	5.20
Price-Earnings ratio, significant unobservable inputs, assets	31.28	112.13
Discount for lack of marketability, significant unobservable inputs, assets	28.00%

Financial Risk Management - Add

Financial Risk Management - Additional Information (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Financial Risk Management [line items]
Foreign exchange gain (loss)	$ (168,499)	$ (41,391)	$ (1,364,929)
Liquidity risk [member]
Disclosure Of Financial Risk Management [line items]
Net current assets	52,664,413
Currency risk [member] | Monetary items [member]
Disclosure Of Financial Risk Management [line items]
Foreign exchange gain (loss)	$ (168,499)	(41,391)	(1,364,929)
Interest rate risk [member] | Floating interest rate [member]
Disclosure Of Financial Risk Management [line items]
Assumed change in interest rate	0.25%
Decrease or increase in net profit (loss) before tax	$ 280,558	$ 216,955	$ 277,612
Revenue from five largest customers [member]
Disclosure Of Financial Risk Management [line items]
Percentage of entity's revenue	38.70%	36.60%

Financial Risk Management - Sch

Financial Risk Management - Schedule of Maturity Analysis for Financial Liabilities (Detail) - Liquidity risk [member] - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Disclosure Of Financial Risk Management [line items]
Financial liabilities and financial instruments, Contractual cash flows	$ 121,692,926	$ 93,831,552
Less than one year [member]
Disclosure Of Financial Risk Management [line items]
Financial liabilities and financial instruments, Contractual cash flows	13,895,628	32,420,981
Later than one year and not later than three years [member]
Disclosure Of Financial Risk Management [line items]
Financial liabilities and financial instruments, Contractual cash flows	55,131,778	45,935,987
Later than three years and not later than five years [member]
Disclosure Of Financial Risk Management [line items]
Financial liabilities and financial instruments, Contractual cash flows	50,630,751	14,395,139
More than five years [member]
Disclosure Of Financial Risk Management [line items]
Financial liabilities and financial instruments, Contractual cash flows	2,034,769	1,079,445
Short-term borrowings [Member]
Disclosure Of Financial Risk Management [line items]
Non-derivative financial liabilities, Contractual cash flows	1,725,602	546,472
Short-term borrowings [Member] | Less than one year [member]
Disclosure Of Financial Risk Management [line items]
Non-derivative financial liabilities, Contractual cash flows	1,725,602	546,472
Long-term borrowings [member]
Disclosure Of Financial Risk Management [line items]
Non-derivative financial liabilities, Contractual cash flows	119,185,207	92,485,536
Long-term borrowings [member] | Less than one year [member]
Disclosure Of Financial Risk Management [line items]
Non-derivative financial liabilities, Contractual cash flows	12,149,855	31,854,500
Long-term borrowings [member] | Later than one year and not later than three years [member]
Disclosure Of Financial Risk Management [line items]
Non-derivative financial liabilities, Contractual cash flows	55,120,591	45,935,987
Long-term borrowings [member] | Later than three years and not later than five years [member]
Disclosure Of Financial Risk Management [line items]
Non-derivative financial liabilities, Contractual cash flows	50,630,751	14,395,139
Long-term borrowings [member] | More than five years [member]
Disclosure Of Financial Risk Management [line items]
Non-derivative financial liabilities, Contractual cash flows	1,284,010	299,910
Guarantee deposits [member]
Disclosure Of Financial Risk Management [line items]
Non-derivative financial liabilities, Contractual cash flows	785,456	816,512
Guarantee deposits [member] | Less than one year [member]
Disclosure Of Financial Risk Management [line items]
Non-derivative financial liabilities, Contractual cash flows	23,510	36,977
Guarantee deposits [member] | Later than one year and not later than three years [member]
Disclosure Of Financial Risk Management [line items]
Non-derivative financial liabilities, Contractual cash flows	11,187
Guarantee deposits [member] | More than five years [member]
Disclosure Of Financial Risk Management [line items]
Non-derivative financial liabilities, Contractual cash flows	750,759	779,535
Foreign currency forward contracts-inflows [member]
Disclosure Of Financial Risk Management [line items]
Derivative financial instruments, Contractual cash flows	(8,731,109)	(12,453,853)
Foreign currency forward contracts-inflows [member] | Less than one year [member]
Disclosure Of Financial Risk Management [line items]
Derivative financial instruments, Contractual cash flows	(8,731,109)	(12,453,853)
Foreign currency forward contracts-outflows [member]
Disclosure Of Financial Risk Management [line items]
Derivative financial instruments, Contractual cash flows	8,727,770	12,436,885
Foreign currency forward contracts-outflows [member] | Less than one year [member]
Disclosure Of Financial Risk Management [line items]
Derivative financial instruments, Contractual cash flows	$ 8,727,770	$ 12,436,885

Financial Risk Management - Dis

Financial Risk Management - Disclosure of Detailed Information About Exposure to Foreign Currency Risk (Detail) - Currency risk [member] € in Thousands, ¥ in Thousands, ¥ in Thousands, $ in Thousands, $ in Thousands	Dec. 31, 2019TWD ($)	Dec. 31, 2019EUR (€)	Dec. 31, 2019USD ($)	Dec. 31, 2019JPY (¥)	Dec. 31, 2018TWD ($)	Dec. 31, 2018EUR (€)	Dec. 31, 2018CNY (¥)	Dec. 31, 2018USD ($)	Dec. 31, 2018JPY (¥)
Monetary items [member] | USD currency [member]
Disclosure Of Financial Risk Management [line items]
Financial assets, Foreign currency amounts			$ 1,499,405					$ 2,092,501
Financial Liabilities, Foreign currency amounts			$ 1,515,582					$ 1,188,175
Exchange rate	30.1350	30.1350	30.1350	30.1350	30.802	30.802	30.802	30.802	30.802
Financial Assets, Carrying Amount	$ 45,184,570				$ 64,453,216
Financial Liabilities, Carrying Amount	$ 45,672,064				$ 36,598,166
Monetary items [member] | JPY currency [member]
Disclosure Of Financial Risk Management [line items]
Financial assets, Foreign currency amounts | ¥				¥ 22,122,120					¥ 11,872,572
Financial Liabilities, Foreign currency amounts | ¥				¥ 22,187,729					¥ 25,296,499
Exchange rate	0.2768	0.2768	0.2768	0.2768	0.2775	0.2775	0.2775	0.2775	0.2775
Financial Assets, Carrying Amount	$ 6,123,403				$ 3,294,639
Financial Liabilities, Carrying Amount	$ 6,141,563				$ 7,019,778
Monetary items [member] | EUR currency [member]
Disclosure Of Financial Risk Management [line items]
Financial assets, Foreign currency amounts | €		€ 46,595				€ 29,681
Financial Liabilities, Foreign currency amounts | €		€ 239				€ 209
Exchange rate	33.7422	33.7422	33.7422	33.7422	35.2036	35.2036	35.2036	35.2036	35.2036
Financial Assets, Carrying Amount	$ 1,572,218				$ 1,044,878
Financial Liabilities, Carrying Amount	$ 8,064				$ 7,358
Nonmonetary items [member] | USD currency [member]
Disclosure Of Financial Risk Management [line items]
Financial assets, Foreign currency amounts			$ 1,726					$ 2,799
Exchange rate	30.1350	30.1350	30.1350	30.1350	30.8020	30.8020	30.8020	30.8020	30.8020
Financial Assets, Carrying Amount	$ 52,013				$ 86,215
Nonmonetary items [member] | RMB currency [member]
Disclosure Of Financial Risk Management [line items]
Financial assets, Foreign currency amounts | ¥							¥ 20,258
Exchange rate	4.3155	4.3155	4.3155	4.3155	4.4813	4.4813	4.4813	4.4813	4.4813
Financial Assets, Carrying Amount					$ 90,782

Financial Risk Management - S_2

Financial Risk Management - Schedule of Sensitivity Analysis of Currency Risk (Detail) - Sensitivity analysis of foreign currency risk [member] - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disclosure Of Financial Risk Management [line items]
Depreciation or appreciation rate of reporting currency	1.00%	1.00%
Depreciation of reporting currency [member]
Disclosure Of Financial Risk Management [line items]
Decrease or increase in net profit (loss) before tax	$ 10,585	$ 251,674
Appreciation of reporting currency [member]
Disclosure Of Financial Risk Management [line items]
Decrease or increase in net profit (loss) before tax	$ (10,585)	$ (251,674)

Capital Management - Schedule o

Capital Management - Schedule of Information about Capital Management (Detail) - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disclosure of objectives, policies and processes for managing capital [abstract]
Short-term borrowings		$ 1,725,602	$ 546,472
Long-term borrowings (including current installments)		111,968,392	86,305,318
Total liabilities		207,455,122	190,765,874
Total equity		$ 178,901,874	$ 207,785,306	$ 212,817,851	$ 176,836,313
Debt-to-equity ratio		116.00%	92.00%
Net debt-to-equity ratio	[1]	19.00%	9.00%
[1]	Net debt-to-equity ratio is defined as short-term borrowings plus long-term borrowings less cash and cash equivalents and divided by total equity.

Related-party Transactions - Di

Related-party Transactions - Disclosure of information about key management personnel (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of related party transactions [Abstract]
Short-term employee benefits	$ 243,203	$ 345,019	$ 566,231
Post-employment benefits	2,633	2,547	2,244
Key management personnel compensation	$ 245,836	$ 347,566	$ 568,475

Related-party Transactions - Sc

Related-party Transactions - Schedule of Sales Transactions Between Related Parties (Detail) - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of transactions between related parties [line items]
Sales		$ 11,575,950	$ 13,948,786	$ 13,176,588
Accounts receivable from related parties		1,778,499	2,754,253
Associates [member]
Disclosure of transactions between related parties [line items]
Sales		1,227,987	1,898,336	1,216,868
Accounts receivable from related parties		280,009	696,423
Others [member]
Disclosure of transactions between related parties [line items]
Sales	[1]	10,347,963	12,050,450	$ 11,959,720
Accounts receivable from related parties	[1]	$ 1,498,490	$ 2,057,830
[1]	Entities which are substantive related parties of the Company but not been accounted for using the equity method, mainly Qisda Corporation and its subsidiaries.

Related-party Transactions - Ad

Related-party Transactions - Additional Information (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related parties [member]
Disclosure of transactions between related parties [line items]
Dividends received	$ 566,865	$ 668,228	$ 420,547
Collection terms for sales [member]
Disclosure of transactions between related parties [line items]
Description of transactions with related party	25 to 55 days from the end of the month during which the invoice is issued.
Payment terms for purchases [member]
Disclosure of transactions between related parties [line items]
Description of transactions with related party	30 to 120 days
Collection Terms For Leasing Facilities [member]
Disclosure of transactions between related parties [line items]
Description of transactions with related party	15 days from quarter-end

Related-party Transactions - _2

Related-party Transactions - Schedule of Purchases Transactions Between Related Parties (Detail) - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of transactions between related parties [line items]
Purchases		$ 26,769,083	$ 29,224,990	$ 27,273,889
Accounts payable to related parties		6,950,828	8,161,186
Associates [member]
Disclosure of transactions between related parties [line items]
Purchases		8,664,439	9,185,563	8,667,555
Accounts payable to related parties		2,825,292	3,664,742
Joint ventures [member]
Disclosure of transactions between related parties [line items]
Purchases		1,027,147	1,449,636	1,057,106
Accounts payable to related parties		72,942	0
Others [member]
Disclosure of transactions between related parties [line items]
Purchases	[1]	17,077,497	18,589,791	$ 17,549,228
Accounts payable to related parties	[1]	$ 4,052,594	$ 4,496,444
[1]	Entities which are substantive related parties of the Company but not been accounted for using the equity method, mainly Qisda Corporation and its subsidiaries.

Related-party Transactions - _3

Related-party Transactions - Schedule of Acquisition of Property, Plant and Equipment in Related Party Transactions (Detail) - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of transactions between related parties [line items]
Acquisition of property, plant and equipment		$ 23,991	$ 10,976	$ 4,350
Associates [member]
Disclosure of transactions between related parties [line items]
Acquisition of property, plant and equipment		6,555	6,527	1,549
Others [member]
Disclosure of transactions between related parties [line items]
Acquisition of property, plant and equipment	[1]	$ 17,436	$ 4,449	$ 2,801
[1]	Entities which are substantive related parties of the Company but not been accounted for using the equity method, mainly Qisda Corporation and its subsidiaries.

Related-party Transactions - _4

Related-party Transactions - Schedule of Disposal of Property, Plant and Equipment in Related Party Transactions (Detail) - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of transactions between related parties [line items]
Proceeds from disposal of property, plant and equipment and others		$ 170,880	$ 6,408,057	$ 1,149,649
Gains on disposals of property, plant and equipment and others		106,546	1,923,044	330,814
Others [member] | Property, Plant and Equipment [Member]
Disclosure of transactions between related parties [line items]
Proceeds from disposal of property, plant and equipment and others	[1]	835	0	3,352
Gains on disposals of property, plant and equipment and others	[1]	$ 72	$ 0	$ 2,212
[1]	Entities which are substantive related parties of the Company but not been accounted for using the equity method, mainly Qisda Corporation and its subsidiaries.

Related-party Transactions - _5

Related-party Transactions - Schedule of Other Receivables Due from Related Parties (Detail) - TWD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Disclosure of transactions between related parties [line items]
Other receivables due from related parties		$ 3,956	$ 12,945
Associates [member]
Disclosure of transactions between related parties [line items]
Other receivables due from related parties		2,727	8,161
Others [member]
Disclosure of transactions between related parties [line items]
Other receivables due from related parties	[1]	$ 1,229	$ 4,784
[1]	Entities which are substantive related parties of the Company but not been accounted for using the equity method, mainly Qisda Corporation and its subsidiaries.

Related-party Transactions - _6

Related-party Transactions - Schedule of Other Payables Due to Related Parties (Detail) - TWD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Disclosure of transactions between related parties [line items]
Other payables due to related parties (including equipment payable)		$ 49,971	$ 28,175
Associates [member]
Disclosure of transactions between related parties [line items]
Other payables due to related parties (including equipment payable)		13,980	18,148
Others [member]
Disclosure of transactions between related parties [line items]
Other payables due to related parties (including equipment payable)	[1]	$ 35,991	$ 10,027
[1]	Entities which are substantive related parties of the Company but not been accounted for using the equity method, mainly Qisda Corporation and its subsidiaries.

Related-party Transactions - _7

Related-party Transactions - Schedule of Rental Income (Detail) - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of transactions between related parties [line items]
Rental income from related parties		$ 166,425	$ 152,877	$ 137,261
Associates [member]
Disclosure of transactions between related parties [line items]
Rental income from related parties		52,227	55,044	48,223
Joint ventures [member]
Disclosure of transactions between related parties [line items]
Rental income from related parties		6,611	6,611	6,611
Others [member]
Disclosure of transactions between related parties [line items]
Rental income from related parties	[1]	$ 107,587	$ 91,222	$ 82,427
[1]	Entities which are substantive related parties of the Company but not been accounted for using the equity method, mainly Qisda Corporation and its subsidiaries.

Related-party Transactions - _8

Related-party Transactions - Schedule of Administration and Other Income (Detail) - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of transactions between related parties [line items]
Administration and other income		$ 26,199	$ 28,429	$ 23,557
Associates [member]
Disclosure of transactions between related parties [line items]
Administration and other income		17,980	18,580	14,311
Joint ventures [member]
Disclosure of transactions between related parties [line items]
Administration and other income		223	1,060	0
Others [member]
Disclosure of transactions between related parties [line items]
Administration and other income	[1]	$ 7,996	$ 8,789	$ 9,246
[1]	Entities which are substantive related parties of the Company but not been accounted for using the equity method, mainly Qisda Corporation and its subsidiaries.

Related-party Transactions - _9

Related-party Transactions - Schedule of Rental and Other Expenses (Detail) - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of transactions between related parties [line items]
Other expenses		$ 79,480	$ 67,058	$ 64,446
Associates [member]
Disclosure of transactions between related parties [line items]
Other expenses		20,157	37,155	28,017
Joint ventures [member]
Disclosure of transactions between related parties [line items]
Other expenses		36	567	1,389
Others [member]
Disclosure of transactions between related parties [line items]
Other expenses	[1]	$ 59,287	$ 29,336	$ 35,040
[1]	Entities which are substantive related parties of the Company but not been accounted for using the equity method, mainly Qisda Corporation and its subsidiaries.

Pledged Assets - Schedule of As

Pledged Assets - Schedule of Assets Pledged As Collateral (Detail) - TWD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Disclosure of Pledged Assets [line items]
Assets pledged as collateral for liabilities or contingent liabilities		$ 71,427,635	$ 65,105,835
Restricted cash in banks [member]
Disclosure of Pledged Assets [line items]
Assets pledged as collateral for liabilities or contingent liabilities	[1]	35,809	91,753
Land and buildings [member]
Disclosure of Pledged Assets [line items]
Assets pledged as collateral for liabilities or contingent liabilities		28,423,642	27,696,480
Machinery and equipment [member]
Disclosure of Pledged Assets [line items]
Assets pledged as collateral for liabilities or contingent liabilities		$ 42,968,184	$ 37,317,602
[1]	Classified as other current financial assets and other noncurrent assets by its liquidity.

Contingent Liabilities and Co_3

Contingent Liabilities and Commitments - Schedule of Outstanding Letters of Credit (Detail) - Dec. 31, 2019 ¥ in Thousands, $ in Thousands	USD ($)	JPY (¥)
Disclosure of contingent liabilities and commitments [abstract]
Outstanding letters of credit	$ 5,768	¥ 1,951,409

Contingent Liabilities and Co_4

Contingent Liabilities and Commitments - Additional Information (Detail) $ in Thousands	Dec. 31, 2019TWD ($)
Disclosure of contingent liabilities and commitments [abstract]
Contractual commitments for acquisition of property, plant and equipment	$ 7,639,758

Segment, Geographic and Reven_3

Segment, Geographic and Revenue Information - Schedule of Operating Segment Information (Detail) - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of operating segments [line items]
Net revenue from external customers		$ 268,791,694	$ 307,634,389	$ 341,028,267
Depreciation and amortization		36,257,719	34,227,530	36,429,836
Inventory write-down		5,185,504	5,171,752	3,756,726
Segment profit (loss)	[1]	(20,467,948)	6,667,865	39,139,124
Other income		5,320,271	5,412,125	3,829,897
Other gains and losses		(1,595,614)	1,488,052	(976,560)
Finance costs		(3,251,370)	(2,663,605)	(2,867,861)
Share of profit of equity-accounted investees		149,907	311,714	239,006
Consolidated profit (loss) before income tax		(19,844,754)	11,216,151	39,363,606
Display segment [Member]
Disclosure of operating segments [line items]
Net revenue from external customers		256,667,222	290,784,754	322,335,330
Depreciation and amortization		35,237,582	32,981,240	34,816,463
Inventory write-down		5,109,473	5,094,195	3,423,097
Segment profit (loss)	[1]	(19,484,401)	7,792,505	39,971,375
Energy segment [Member]
Disclosure of operating segments [line items]
Net revenue from external customers		12,124,472	16,849,635	18,692,937
Depreciation and amortization		1,020,137	1,246,290	1,613,373
Inventory write-down		76,031	77,557	333,629
Segment profit (loss)	[1]	$ (983,547)	$ (1,124,640)	$ (832,251)
[1]	There were no intersegment revenues or other transactions between operating segments for the years ended December 31, 2017, 2018 and 2019.

Segment, Geographic and Reven_4

Segment, Geographic and Revenue Information - Schedule of Net Revenue from External Customers and Noncurrent Assets (Detail) - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of geographical areas [line items]
Net revenue from external customers		$ 268,791,694	$ 307,634,389	$ 341,028,267
Non-current assets	[1]	224,430,518	229,585,095
PRC [Member]
Disclosure of geographical areas [line items]
Net revenue from external customers		98,362,235	113,632,037	125,341,648
Non-current assets	[1]	54,890,846	61,284,667
Taiwan ROC [Member]
Disclosure of geographical areas [line items]
Net revenue from external customers		83,229,594	99,357,882	108,288,387
Non-current assets	[1]	163,237,676	161,358,754
Singapore [Member]
Disclosure of geographical areas [line items]
Net revenue from external customers		38,534,291	39,370,930	35,939,290
Japan [Member]
Disclosure of geographical areas [line items]
Net revenue from external customers		20,924,003	21,166,864	32,739,262
Others [Member]
Disclosure of geographical areas [line items]
Net revenue from external customers		27,741,571	34,106,676	$ 38,719,680
Non-current assets	[1]	$ 6,301,996	$ 6,941,674
[1]	Noncurrent assets are not inclusive of financial instruments, deferred tax assets, and prepaid pension.

Segment, Geographic and Reven_5

Segment, Geographic and Revenue Information - Schedule of Revenue By Major Customers (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of major customers [line items]
Revenue	$ 268,791,694	$ 307,634,389	$ 341,028,267
Customer A [member]
Disclosure of major customers [line items]
Revenue	$ 33,142,985	$ 35,358,013	$ 43,645,518
Percentage of consolidated net revenue	12.00%	11.00%	13.00%

Segment, Geographic and Reven_6

Segment, Geographic and Revenue Information - Schedule of Consolidated Net Revenue by Principal Products (Detail) - TWD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of products and services [line items]
Revenue		$ 268,791,694	$ 307,634,389	$ 341,028,267
Televisions [member]
Disclosure of products and services [line items]
Revenue		87,269,763	113,194,567	152,442,198
Mobile PCs and Devices [member]
Disclosure of products and services [line items]
Revenue		69,305,510	74,375,305	71,068,304
Monitors [member]
Disclosure of products and services [line items]
Revenue		39,522,268	47,024,353	45,696,144
Commercial and Others [member]
Disclosure of products and services [line items]
Revenue	[1]	60,569,681	56,190,529	53,128,684
Solar Products [member]
Disclosure of products and services [line items]
Revenue		$ 12,124,472	$ 16,849,635	$ 18,692,937
[1]	Others include sales from products for other applications and sales of raw materials, components and from service charges.

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - Major ordinary share transactions [member] - ADLINK Technology Inc [member] shares in Thousands	Mar. 12, 2020$ / sharesshares
Disclosure of non-adjusting events after reporting period [line items]
Tender offer, description	On February 5, 2020, AUO's Board of Directors resolved to acquire common shares of ADLINK Technology Inc. through tender offer.
Shares acquired | shares	42,310
Common shraes offer consideration | $ / shares	$ 57
Percentage of equity interest acquired	19.45%