Amkor Technology (AMKR) 10-Q 1 Aug 14 2014 Q2 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information Document	6 Months Ended
	Jun. 30, 2014	Jul. 25, 2014
Document Information [Line Items]	'	'
Entity Registrant Name	'AMKOR TECHNOLOGY INC	'
Entity Central Index Key	'0001047127	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Accelerated Filer	'
Document Type	'10-Q	'
Document Period End Date	30-Jun-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q2	'
Amendment Flag	'false	'
Entity Common Stock, Shares Outstanding	'	237,106,589

Consolidated_Statements_of_Inc

Consolidated Statements of Income (Unaudited) (USD $)	3 Months Ended		6 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Net sales	$767,459	$746,059	$1,463,503	$1,433,588
Cost of sales	616,745	607,680	1,183,969	1,180,256
Gross profit	150,714	138,379	279,534	253,332
Selling, general and administrative	67,674	65,618	130,098	125,177
Research and development	22,079	14,308	43,124	28,614
Total operating expenses	89,753	79,926	173,222	153,791
Operating income	60,961	58,453	106,312	99,541
Interest expense	22,537	23,739	46,259	45,817
Interest expense, related party	1,242	3,192	2,484	6,684
Other (income) expense, net	-5,699	12,876	-5,663	10,654
Total other expense, net	18,080	39,807	43,080	63,155
Income before taxes and equity in earnings of unconsolidated affiliate	42,881	18,646	63,232	36,386
Income tax expense (benefit)	12,511	-10,238	17,440	-6,209
Income before equity in earnings of unconsolidated affiliate	30,370	28,884	45,792	42,595
Equity in earnings of J-Devices	20,036	1,445	25,797	1,500
Net income	50,406	30,329	71,589	44,095
Net income attributable to noncontrolling interests	-885	-602	-1,435	-986
Net income attributable to Amkor	$49,521	$29,727	$70,154	$43,109
Net income attributable to Amkor per common share:	'	'	'	'
Basic (in dollars per share)	$0.21	$0.18	$0.31	$0.27
Diluted (in dollars per share)	$0.21	$0.14	$0.30	$0.21
Shares used in computing per common share amounts:	'	'	'	'
Basic (in shares)	232,891	160,886	224,868	156,672
Diluted (in shares)	236,872	235,111	236,182	235,099

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (Unaudited) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Net income	$50,406	$30,329	$71,589	$44,095
Other comprehensive income (loss), net of tax:	'	'	'	'
Adjustments to unrealized components of defined benefit pension plans, net of tax of ($345), ($9), ($366) and $49	486	75	606	217
Foreign currency translation adjustment	-12,493	-744	-11,808	-3,100
Equity interest in J-Devices' other comprehensive income (loss), net of tax of $0, ($1,087), $0 and $202	562	-2,155	3,706	-4,051
Total other comprehensive loss	-11,445	-2,824	-7,496	-6,934
Comprehensive income	38,961	27,505	64,093	37,161
Comprehensive income attributable to noncontrolling interests	-885	-602	-1,435	-986
Comprehensive income attributable to Amkor	$38,076	$26,903	$62,658	$36,175

Consolidated_Statements_of_Com1

Consolidated Statements of Comprehensive Income (Parenthetical) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Adjustments to unrealized components of defined benefit pension plans, tax effect	($345)	($9)	($366)	$49
Equity interest in J-Devices' other comprehensive loss, tax effect	$0	($1,087)	$0	$202

Consolidated_Balance_Sheets_Un

Consolidated Balance Sheets (Unaudited) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$525,935	$610,442
Restricted cash	2,681	2,681
Accounts receivable, net of allowances	455,838	385,542
Inventories	205,668	200,423
Other current assets	57,803	33,328
Total current assets	1,247,925	1,232,416
Property, plant and equipment, net	2,153,818	2,006,553
Investments	134,717	105,214
Restricted cash	2,247	2,234
Other assets	70,666	80,881
Total assets	3,609,373	3,427,298
Current liabilities:	'	'
Short-term borrowings and current portion of long-term debt	10,000	61,350
Trade accounts payable	555,805	365,334
Accrued expenses	252,048	264,252
Total current liabilities	817,853	690,936
Long-term debt	1,451,111	1,516,390
Long-term debt, related party	75,000	75,000
Pension and severance obligations	159,936	165,073
Other non-current liabilities	14,423	14,959
Total liabilities	2,518,323	2,462,358
Commitments and contingencies (Note 17)	'	'
Amkor stockholders’ equity:	'	'
Preferred stock, $0.001 par value, 10,000 shares authorized, designated Series A, none issued	'	'
Common stock, $0.001 par value, 500,000 shares authorized, 281,782 and 262,109 shares issued, and 236,252 and 216,702 shares outstanding, in 2014 and 2013, respectively	282	262
Additional paid-in capital	1,875,533	1,812,530
Accumulated deficit	-577,194	-647,348
Accumulated other comprehensive loss	-7,751	-255
Treasury stock, at cost, 45,530 and 45,407 shares in 2014 and 2013, respectively	-212,455	-211,449
Total Amkor stockholders’ equity	1,078,415	953,740
Noncontrolling interests in subsidiaries	12,635	11,200
Total equity	1,091,050	964,940
Total liabilities and equity	$3,609,373	$3,427,298

Consolidated_Balance_Sheets_Un1

Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, except Per Share data, unless otherwise specified
Amkor stockholders’ equity:	'	'
Preferred stock designated Series A, par value (in dollars per share)	$0.00	$0.00
Preferred stock designated Series A, shares authorized	10,000	10,000
Preferred stock designated Series A, shares issued	0	0
Common stock, par value (in dollars per share)	$0.00	$0.00
Common stock, shares authorized	500,000	500,000
Common stock, shares issued	281,782	262,109
Common stock, shares outstanding	236,252	216,702
Treasury stock, shares	45,530	45,407

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
			Related Party [Member]	Related Party [Member]
			Convertible Senior Subordinated Notes Due April 2014 [Member]	Convertible Senior Subordinated Notes Due April 2014 [Member]
Cash flows from operating activities:	'	'	'	'
Net income	$71,589	$44,095	'	'
Depreciation and amortization	220,389	195,785	'	'
Loss on debt retirement	0	11,619	'	'
Gain on sale of subsidiary to J-Devices	-9,155	0	'	'
Other operating activities and non-cash items	-24,000	-13,947	'	'
Changes in assets and liabilities	-23,570	-36,702	'	'
Net cash provided by operating activities	235,253	200,850	'	'
Cash flows from investing activities:	'	'	'	'
Payments for property, plant and equipment	-230,392	-222,674	'	'
Proceeds from sale of property, plant and equipment	1,634	25,093	'	'
Cash transferred on sale of subsidiary to J-Devices, net of proceeds	-15,774	0	'	'
Payments from J-Devices	0	8,843	'	'
Investment in J-Devices	0	-67,372	'	'
Payments to Acquire Short-term Investments	-20,000	0	'	'
Proceeds from Sale of Short-term Investments	20,000	0	'	'
Other investing activities	-353	-2,032	'	'
Net cash used in investing activities	-244,885	-258,142	'	'
Cash flows from financing activities:	'	'	'	'
Borrowings under revolving credit facilities	0	5,000	'	'
Payments under revolving credit facilities	0	-5,000	'	'
Proceeds from issuance of long-term debt	80,000	293,000	'	'
Payments of long-term debt	-140,000	0	'	'
Payments for debt issuance costs	0	-3,357	'	'
Payments for the retirement of debt	0	-11,619	'	'
Payment of deferred consideration for an acquisition	-18,763	0	'	'
Proceeds from the issuance of stock through share-based compensation plans	4,826	0	'	'
Payments of tax withholding for restricted shares	-1,006	-172	'	'
Net cash (used in) provided by financing activities	-74,943	277,852	'	'
Effect of exchange rate fluctuations on cash and cash equivalents	68	2,399	'	'
Net (decrease) increase in cash and cash equivalents	-84,507	222,959	'	'
Cash and cash equivalents, beginning of period	610,442	413,048	'	'
Cash and cash equivalents, end of period	525,935	636,007	'	'
Non cash investing and financing activities:	'	'	'	'
Common stock issuance for conversion and exchange in 2014 and 2013, respectively, of 6.0% Convertible senior subordinated notes due April 2014, $150 million related party in 2013	$56,350	$193,650	$0	$150,000

Interim_Financial_Statements

Interim Financial Statements	6 Months Ended
	Jun. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Interim Financial Statements	'
	1.    Interim Financial Statements
	Basis of Presentation. The Consolidated Financial Statements and related disclosures as of June 30, 2014, and for the three and six months ended June 30, 2014 and 2013, are unaudited, pursuant to the rules and regulations of the United States Securities and Exchange Commission (“SEC”). The December 31, 2013, Consolidated Balance Sheet data was derived from audited financial statements, but does not include all disclosures required by accounting principles generally accepted in the United States of America (“U.S.”). Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) have been condensed or omitted pursuant to such rules and regulations. In our opinion, these financial statements include all adjustments (consisting only of normal recurring adjustments) necessary for the fair statement of the results for the interim periods. These financial statements should be read in conjunction with the financial statements included in our Annual Report for the year ended December 31, 2013, filed on Form 10-K with the SEC on February 28, 2014. The results of operations for the three and six months ended June 30, 2014, are not necessarily indicative of the results to be expected for the full year. Unless the context otherwise requires, all references to “Amkor,” “we,” “us,” “our” or the “company” are to Amkor Technology, Inc. and our subsidiaries.
	On June 30, 2014, we completed the sale of our Japanese subsidiary to J-Devices, our 60% owned equity-method joint venture in Japan. The financial results of the entity were included in our consolidated financial statements up to the date of sale (Note 4). On July 31, 2013, we completed the purchase of Toshiba Electronics Malaysia Sdn. Bhd. The financial results of the entity have been included in our Consolidated Financial Statements from the date of acquisition (Note 3).
	The U.S. dollar is our reporting currency and the functional currency for our foreign subsidiaries. Effective June 30, 2014, we changed the functional currency for our sales office in Japan to the U.S. dollar primarily due to an increase in the mix of our U.S. dollar denominated sales. The change in functional currency is applied on a prospective basis.
	Beginning with the year ended December 31, 2013, we reclassified equity in earnings of unconsolidated affiliate from other expense (income) to below income tax expense in our Consolidated Statements of Income for all periods presented. The reclassification had no impact on net income.
	Use of Estimates. The Consolidated Financial Statements have been prepared in conformity with U.S. GAAP, using management’s best estimates and judgments where appropriate. These estimates and judgments affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements. The estimates and judgments will also affect the reported amounts for certain revenues and expenses during the reporting period. Actual results could differ materially from these estimates and judgments.

New_Accounting_Standards

New Accounting Standards	6 Months Ended
	Jun. 30, 2014
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]	'
New Accounting Standards	'
	2.    New Accounting Standards
	Recently Adopted Standards
	In March 2013, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2013-05, Parent's Accounting for the Cumulative Translation Adjustment upon Derecognition of Certain Subsidiaries or Groups of Assets within a Foreign Entity or of an Investment in a Foreign Entity (Topic 830). ASU 2013-05 provides guidance to resolve the diversity in practice regarding the release into net income of the cumulative translation adjustment when a company sells or ceases to hold a controlling interest in a subsidiary or group of assets within a foreign entity. This ASU is effective for reporting periods beginning after December 15, 2013. ASU 2013-05 was adopted on January 1, 2014. On June 30, 2014, we sold our controlling interest in a foreign subsidiary. The sale resulted in a gain upon release of the cumulative translation adjustment associated with the entity (Note 4).
	Recently Issued Standards
	In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606). ASU 2014-09 is based on the principle that revenue is recognized to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. This ASU also requires additional disclosure about the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers, including significant judgments and changes in judgments. ASU 2014-09 is effective for reporting periods beginning after December 15, 2016, and permits the use of either full retrospective or modified retrospective methods of adoption. Early adoption is not permitted. We are currently evaluating the method of adoption and the impact that this guidance will have on our financial statements and disclosure.

Business_Acquisitions_Business

Business Acquisitions Business Acquisitions	6 Months Ended
	Jun. 30, 2014
Business Combinations [Abstract]	'
Business Combination Disclosure [Text Block]	'
	3.    Business Acquisitions
	On July 31, 2013, we completed the purchase of 100% of the shares of Toshiba Electronics Malaysia Sdn. Bhd., Toshiba’s power discrete semiconductor packaging and test operation in Malaysia, and subsequently changed the name of the entity to Amkor Technology Malaysia Sdn. Bhd. The total price for the shares was $61.2 million, based on the net asset value at closing. We paid $42.4 million in cash at closing and paid the remaining $18.8 million in March 2014. We were also granted a non-exclusive, royalty bearing license by Toshiba to certain intellectual property rights for providing packaging and test services for power discrete and certain other semiconductor products. The license has a royalty cap of ¥1.5 billion (approximately $15 million). Under the purchase method of accounting, we allocated the purchase price to the assets acquired and liabilities assumed based on their estimated fair values on the date of acquisition. We did not record any goodwill as a result of the acquisition.

Sale_of_Subsidiary_of_JDevices

Sale of Subsidiary of J-Devices Sale of Subsidiary of J-Devices	6 Months Ended
	Jun. 30, 2014
Disposal Group, Not Discontinued Operation, Disposal Disclosures [Abstract]	'
Disposal Groups, Including Discontinued Operations, Disclosure [Text Block]	'
	4.    Sale of Subsidiary to J-Devices
	On June 30, 2014, we sold 100% of the shares of our wholly-owned subsidiary engaged in semiconductor packaging and test operations in Japan to J-Devices Corporation ("J-Devices"), our 60% owned equity-method joint venture in Japan, for ¥1.1 billion ($11.1 million). For additional information regarding our investment in J-Devices, we refer you to Note 12. We received ¥0.1 billion ($1.0 million) in cash from J-Devices at closing and will receive the remaining ¥1.0 billion ($10.1 million) by June 30, 2015. We recognized a net gain on the sale of $9.2 million in our consolidated financial statements in other (income) expense, net, which includes a gain of $12.6 million from the release of accumulated foreign currency translation adjustments associated with the entity (Note 9). J-Devices recognized a gain of $14.7 million on the transaction in its consolidated financial statements as the fair value of the net assets acquired exceeded the purchase price. The gain recognized by J-Devices increased our equity in earnings of J-Devices by $8.8 million for the three and six months ended June 30, 2014. The combined net gain we recognized for the three and six months ended June 30, 2014, was $18.0 million.

ShareBased_Compensation_Plans

Share-Based Compensation Plans	6 Months Ended
	Jun. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Share-Based Compensation Plans	'
	5.    Share-Based Compensation Plans
	The following table presents share-based compensation expense attributable to stock options and restricted shares.
		For the Three Months Ended								For the Six Months Ended
		June 30,								June 30,
		2014				2013				2014			2013
		(In thousands)
	Stock options	$	386			$	151			$	777		$	255
	Restricted shares	489				497				1,070			927
	Total share-based compensation expense	$	875			$	648			$	1,847		$	1,182
	The following table presents share-based compensation expense as included in the Consolidated Statements of Income:
		For the Three Months Ended								For the Six Months Ended
		June 30,								June 30,
		2014				2013				2014			2013
		(In thousands)
	Selling, general and administrative	$	764			$	565			1,613			1,030
	Research and development	111				83				234			152
	Total share-based compensation expense	$	875			$	648			$	1,847		$	1,182
	There is no corresponding deferred income tax benefit for stock options or restricted shares.
	Stock Options
	The following table summarizes our stock option activity for the six months ended June 30, 2014:
		Number of			Weighted Average				Weighted Average		Aggregate
		Shares			Exercise Price				Remaining		Intrinsic
		(In thousands)			Per Share				Contractual		Value
									Term (Years)		(In thousands)
	Outstanding at December 31, 2013	4,873			$	6.52
	Granted	260			7.64
	Exercised	(747	)		6.46
	Forfeited or expired	(340	)		12.3
	Outstanding at June 30, 2014	4,046			$	6.12			6.58		$	20,566
	Fully vested at June 30, 2014 and expected to vest thereafter	4,015			$	6.13			6.56		$	20,373
	Exercisable at June 30, 2014	1,955			$	7.55			3.84		$	7,197
	The following assumptions were used to calculate the weighted average fair values of the options granted:
		For the Three Months Ended								For the Six Months Ended
		June 30,								June 30,
		2014				2013				2014			2013
	Expected life (in years)	6				6.2				6.1			6.2
	Risk-free interest rate	2		%		1		%		2		%	1		%
	Volatility	57		%		60		%		58		%	60		%
	Dividend yield	—				—				—			—
	Weighted average grant date fair value per option granted	$	5.01			$	2.53			$	4.2		$	2.53
	Total unrecognized compensation expense from stock options, net of a forfeiture estimate, was $4.8 million as of June 30, 2014, which is expected to be recognized over a weighted-average period of approximately 3.0 years beginning July 1, 2014.
	Restricted Shares
	The following table summarizes our restricted share activity for the six months ended June 30, 2014:
		Number of			Weighted
		Shares			Average
		(In thousands)			Grant-Date
					Fair Value
					(Per share)
	Nonvested at December 31, 2013	1,172			$	4.83
	Awards granted	—			—
	Awards vested	(294	)		5.09
	Awards forfeited	(11	)		4.84
	Nonvested at June 30, 2014	867			$	4.74
	Total unrecognized compensation cost, net of a forfeiture estimate, was $3.4 million as of June 30, 2014, which is expected to be recognized over a weighted average period of approximately 2.5 years beginning July 1, 2014.

Other_Income_and_Expense_Notes

Other Income and Expense (Notes)	6 Months Ended
	Jun. 30, 2014
Other Income and Expenses [Abstract]	'
Other Income and Other Expense Disclosure [Text Block]	'
	6.    Other Income and Expense
	Other income and expense consists of the following:
		For the Three Months Ended						For the Six Months Ended
		June 30,						June 30,
		2014			2013			2014			2013
		(In thousands)
	Interest income	$	(831	)	$	(676	)	$	(1,542	)	$	(1,503	)
	Foreign currency loss, net	4,213			2,041			4,547			875
	Loss on debt retirement	622			11,619			757			11,619
	Gain on sale of subsidiary to J-Devices (Note 4)	(9,155		)	—			(9,155		)	—
	Other income, net	(548		)	(108		)	(270		)	(337		)
	Total other (income) expense, net	$	(5,699	)	$	12,876		$	(5,663	)	$	10,654

Income_Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2014
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	7.    Income Taxes
	Our income tax expense of $17.4 million for the six months ended June 30, 2014, primarily reflects expense related to income taxes at certain of our foreign operations and foreign withholding taxes. Our income tax expense also reflects income taxed in foreign jurisdictions where we benefit from tax holidays.
	We maintain a valuation allowance on all of our U.S. net deferred tax assets, including our net operating loss carryforwards. We also have valuation allowances on deferred tax assets in certain foreign jurisdictions. Such valuation allowances are released as the related tax benefits are realized or when sufficient net positive evidence exists to conclude that it is more likely than not that the deferred tax assets will be realized.
	Unrecognized tax benefits represent reserves for potential tax deficiencies or reductions in tax benefits that could result from federal, state or foreign tax audits. Our gross unrecognized tax benefits decreased from $27.1 million at December 31, 2013, to $6.9 million as of June 30, 2014, primarily as a result of the application of a tax law change and the settlement of a tax examination in a certain foreign jurisdiction. At June 30, 2014, all of our unrecognized tax benefits would reduce our effective tax rate, if recognized. Our unrecognized tax benefits are subject to change as examinations of tax years are completed. Tax return examinations involve uncertainties, and there can be no assurances that the outcome of examinations will be favorable.

Earnings_Per_Share

Earnings Per Share	6 Months Ended
	Jun. 30, 2014
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	8.    Earnings Per Share
	Basic earnings per share (“EPS”) is computed by dividing net income attributable to Amkor common stockholders by the weighted average number of common shares outstanding during the period. The weighted average number of common shares outstanding includes restricted shares held by retirement eligible recipients and is reduced for treasury stock. We grant restricted shares which entitle recipients to voting and nonforfeitable dividend rights from the date of grant therefore our unvested share-based compensation awards are considered participating securities and are included in the computation of EPS pursuant to the two-class method.
	Diluted EPS is computed on the basis of the weighted average number of shares of common stock plus the effect of dilutive potential common shares outstanding during the period. Dilutive potential common shares include outstanding stock options, unvested restricted shares and convertible debt. The following table summarizes the computation of basic and diluted EPS:
		For the Three Months Ended							For the Six Months Ended
		June 30,							June 30,
		2014				2013			2014			2013
		(In thousands, except per share data)
	Net income attributable to Amkor	$	49,521			$	29,727		$	70,154		$	43,109
	Income allocated to participating securities	(184		)		(251		)	(269		)	(374		)
	Net income available to Amkor common stockholders — basic	49,337				29,476			69,885			42,735
	Adjustment for dilutive securities on net income:
	Net income reallocated to participating securities	3				58			9			80
	Interest on 6.0% convertible notes due 2014, net of tax	132				3,609			1,039			7,626
	Net income attributable to Amkor — diluted	$	49,472			$	33,143		$	70,933		$	50,441
	Weighted average shares outstanding — basic	232,891				160,886			224,868			156,672
	Effect of dilutive securities:
	Stock options	1,115				10			609			14
	6.0% convertible notes due 2014	2,866				74,215			10,705			78,413
	Weighted average shares outstanding — diluted	236,872				235,111			236,182			235,099
	Net income attributable to Amkor per common share:
	Basic	$	0.21			$	0.18		$	0.31		$	0.27
	Diluted	0.21				0.14			0.3			0.21
	The following table summarizes the potential shares of common stock that were excluded from diluted EPS, because the effect of including these potential shares was antidilutive:
		For the Three Months Ended						For the Six Months Ended
		June 30,						June 30,
		2014			2013			2014		2013
		(In thousands)
	Stock options and restricted share awards	1,114			4,092			1,563		4,165

Equity_and_Accumulated_Other_C

Equity and Accumulated Other Comprehensive Income	6 Months Ended
	Jun. 30, 2014
Equity [Abstract]	'
Equity and Accumulated Other Comprehensive Income	'
	9.    Equity and Accumulated Other Comprehensive Income
	The following table reflects the changes in equity attributable to both Amkor and the noncontrolling interests:
		Attributable			Attributable to			Total
		to Amkor			Noncontrolling
					Interests
		(In thousands)
	Equity at December 31, 2013	$	953,740		$	11,200		$	964,940
	Net income	70,154			1,435			71,589
	Other comprehensive loss	(7,496		)	—			(7,496		)
	Issuance of stock through employee share-based compensation plans	4,826			—			4,826
	Treasury stock acquired through surrender of shares for tax withholding	(1,006		)	—			(1,006		)
	Share-based compensation expense	1,847			—			1,847
	Conversion of debt to common stock	56,350			—			56,350
	Equity at June 30, 2014	$	1,078,415		$	12,635		$	1,091,050
		Attributable			Attributable to			Total
		to Amkor			Noncontrolling
					Interests
		(In thousands)
	Equity at December 31, 2012	$	657,955		$	8,839		$	666,794
	Net income	43,109			986			44,095
	Other comprehensive loss	(6,934		)	—			(6,934		)
	Treasury stock acquired through surrender of shares for tax withholding	(172		)	—			(172		)
	Share-based compensation expense	1,182			—			1,182
	Exchange of debt for common stock	195,034			—			195,034
	Equity at June 30, 2013	$	890,174		$	9,825		$	899,999
	The following table reflects the changes in accumulated other comprehensive income and loss, net of tax:
		Defined Benefit Pension			Foreign Currency Translation			Equity Interest in J-Devices' Other Comprehensive Income (Loss)			Total
		(In thousands)
	Accumulated other comprehensive (loss) income at	$	(1,013	)	$	11,451		$	(10,693	)	$	(255	)
	31-Dec-13
	Other comprehensive income before reclassifications	—			779			3,706			4,485
	Amounts reclassified from accumulated other comprehensive (loss) income	606			(12,587		)	—			(11,981		)
	Other comprehensive income (loss)	606			(11,808		)	3,706			(7,496		)
	Accumulated other comprehensive loss at	$	(407	)	$	(357	)	$	(6,987	)	$	(7,751	)
	30-Jun-14
		Defined Benefit Pension			Foreign Currency Translation			Equity Interest in J-Devices' Other Comprehensive Income (Loss)			Total
		(In thousands)
	Accumulated other comprehensive (loss) income at	$	(5,373	)	$	16,346		$	268		$	11,241
	31-Dec-12
	Other comprehensive loss before reclassifications	—			(3,100		)	(4,051		)	(7,151		)
	Amounts reclassified from accumulated other comprehensive (loss) income	217			—			—			217
	Other comprehensive income (loss)	217			(3,100		)	(4,051		)	(6,934		)
	Accumulated other comprehensive (loss) income at	$	(5,156	)	$	13,246		$	(3,783	)	$	4,307
	30-Jun-13
	Amounts reclassified out of accumulated other comprehensive (loss) income are included as a component of net periodic pension cost (Note 15) or other (income) expense, net as a result of the release of accumulated foreign currency translation adjustments associated with the sale of our subsidiary in Japan (Note 4).

Inventories

Inventories	6 Months Ended
	Jun. 30, 2014
Inventory Disclosure [Abstract]	'
Inventories	'
	10.    Inventories
	Inventories consist of the following:
		June 30,		December 31, 2013
		2014
		(In thousands)
	Raw materials and purchased components	$	147,280	$	147,292
	Work-in-process	58,388		53,131
	Total inventories	$	205,668	$	200,423

Property_Plant_and_Equipment

Property, Plant and Equipment	6 Months Ended
	Jun. 30, 2014
Property, Plant and Equipment [Abstract]	'
Property, Plant And Equipment	'
	11.    Property, Plant and Equipment
	Property, plant and equipment consist of the following:
		June 30,			December 31, 2013
		2014
		(In thousands)
	Land	$	207,986		$	208,048
	Land use rights	26,845			26,845
	Buildings and improvements	919,379			911,258
	Machinery and equipment	3,748,385			3,577,045
	Software and computer equipment	206,247			193,641
	Furniture, fixtures and other equipment	15,453			17,430
	Construction in progress	48,430			27,039
	Total property, plant and equipment	5,172,725			4,961,306
	Less accumulated depreciation and amortization	(3,018,907		)	(2,954,753		)
	Total property, plant and equipment, net	$	2,153,818		$	2,006,553
	The following table presents depreciation expense as included in the Consolidated Statements of Income:
		For the Three Months Ended						For the Six Months Ended
		June 30,						June 30,
		2014			2013			2014		2013
		(In thousands)
	Cost of sales	$	101,594		$	90,805		$	201,361	$	179,973
	Selling, general and administrative	3,926			3,860			7,362		7,995
	Research and development	6,240			3,114			11,073		6,109
	Total depreciation expense	$	111,760		$	97,779		$	219,796	$	194,077
	As of June 30, 2014, we have capitalized interest of $5.1 million associated with our spending for land and design costs in anticipation of building a new factory and research and development center in Korea.

Investments

Investments	6 Months Ended
	Jun. 30, 2014
Investments, All Other Investments [Abstract]	'
Investments	'
	12.    Investments
	Investments consist of the following:
		June 30,				December 31,
		2014				2013
		Carrying		Ownership		Carrying		Ownership
		Value		Interest		Value		Interest
		(In thousands)				(In thousands)
	Investment in unconsolidated affiliate	$	134,717	60	%	$	105,214	60	%
	J-Devices Corporation
	In October 2009, Amkor and Toshiba Corporation (“Toshiba”) invested in Nakaya Microdevices Corporation (“NMD”) and formed a joint venture to provide semiconductor packaging and test services in Japan. As a result of the transaction, NMD changed its name to J-Devices. We invested $16.7 million for our original 30% equity interest and options to acquire additional equity interests. In April 2013, we completed the exercise of our option to increase our ownership interest in J-Devices from 30% to 60% for an aggregate purchase price of $67.4 million. J-Devices is owned 60% by Amkor, 34% by the former shareholders of NMD and 6% by Toshiba.
	On June 30, 2014, J-Devices purchased 100% of the shares of our wholly-owned subsidiary engaged in semiconductor packaging and test operations in Japan. For additional information regarding this transaction, we refer you to Note 4.
	At June 30, 2014, our investment includes our 60% equity interest and options to acquire additional equity interests. The remaining options are exercisable at our discretion and permit us to increase our ownership interest in J-Devices up to 66% in 2014 by purchasing shares owned by Toshiba and up to 80% in 2015 and thereafter by purchasing shares owned by the other shareholders. In 2014 and beyond, Toshiba has the option, at its discretion, to sell shares it owns to us. If we decline Toshiba's offer to sell its shares to us, then J-Devices shall have the obligation to purchase the shares. If J-Devices is unable to fulfill its obligation to purchase the shares offered by Toshiba, then we will be obligated to purchase the shares offered by Toshiba. The options in 2014 and 2015 become exercisable in the fourth quarter of such year, and if exercised, we would expect closing to occur in the first half of the following year, subject to regulatory approval. After we own 80% or more shares, the original shareholders of NMD have a put option which allows them to sell their shares to us. The exercise price for all options is payable in cash and is determined using a formula based on the net book value and a multiple of earnings before interest, taxes, depreciation and amortization of J-Devices.
	The governance provisions currently applicable to J-Devices restrict our ability, even with our majority ownership, to cause J-Devices to take certain actions without the consent of the other investors. Accordingly, we account for our investment in J-Devices using the equity method of accounting. Under the equity method of accounting, we recognize our proportionate share of J-Devices' net income or loss, which is after J-Devices' income taxes in Japan, during each accounting period as a change in our investment in unconsolidated affiliate. J-Devices' financial information is converted to U.S. GAAP and translated into U.S. dollars using Japanese yen as the functional currency. In addition, we record equity method adjustments as a change in our investment. The equity method adjustments include the amortization of basis differences as a result of the cost of our investment differing from our proportionate share of J-Devices' equity.

Accrued_Expenses

Accrued Expenses	6 Months Ended
	Jun. 30, 2014
Payables and Accruals [Abstract]	'
Accrued Expenses	'
	13.    Accrued Expenses
	Accrued expenses consist of the following:
		June 30,		December 31,
		2014		2013
		(In thousands)
	Payroll and benefits	$	69,629	$	75,909
	Deferred revenue and customer advances	52,822		44,764
	Accrued royalties (Note 17)	43,324		43,324
	Accrued interest	21,369		21,807
	Income taxes payable	17,117		17,528
	Accrued severance plan obligations (Note 15)	11,794		11,197
	Acquisition payable (Note 3)	—		17,897
	Other accrued expenses	35,993		31,826
	Total accrued expenses	$	252,048	$	264,252
	Accrued royalties relate to our estimate of royalties due as a result of our pending patent license litigation (Note 17).

Debt

Debt	6 Months Ended
	Jun. 30, 2014
Debt Disclosure [Abstract]	'
Debt	'
	14.    Debt
	Following is a summary of short-term borrowings and long-term debt:
		June 30,			December 31,
		2014			2013
		(In thousands)
	Debt of Amkor Technology, Inc.:
	Senior secured credit facilities:
	$150 million revolving credit facility, LIBOR plus 1.5%-2.25%, due June 2017	$	—		$	—
	Senior notes:
	7.375% Senior notes, due May 2018	345,000			345,000
	6.625% Senior notes, due June 2021, $75 million related party	400,000			400,000
	6.375% Senior notes, due October 2022	525,000			525,000
	Senior subordinated notes:
	6.0% Convertible senior subordinated notes, due April 2014 (1)	—			56,350
	Debt of subsidiaries:
	Amkor Technology Korea, Inc.:
	$41 million revolving credit facility, foreign currency funding-linked base rate plus 2.00%, due June 2016	—			—
	Term loan, LIBOR plus 3.70%, due June 2016 (2)	70,000			70,000
	Term loan, foreign currency funding-linked base rate plus 2.00%, due March 2017 (3)	80,000			—
	Term loan, LIBOR plus 3.90% or 3.94%, due July 2017 (4)	30,000			90,000
	Term loan, foreign currency funding-linked base rate plus 1.75%, due September 2017 (5)	10,000			10,000
	Term loan, LIBOR plus 3.70%, due December 2019	70,000			70,000
	Term loan, foreign currency funding-linked base rate plus 2.30%, due March 2015 (3)	—			80,000
	Other:
	Revolving credit facility, TAIFX plus a bank-determined spread, due April 2015 (Taiwan) (6)	—			—
		1,530,000			1,646,350
	Add: Unamortized premium	6,111			6,390
	Less: Short-term borrowings and current portion of long-term debt	(10,000		)	(61,350		)
	Long-term debt (including related party)	$	1,526,111		$	1,591,390
	-1	In April 2009, we issued $250.0 million of our 6.0% Convertible senior subordinated notes due April 2014 (the “2014 Notes”). The 2014 Notes were convertible at any time prior to the maturity date into our common stock at a price of approximately $3.02 per share, subject to adjustment. In June 2013, we completed a tender offer for the 2014 Notes and exchanged $193.7 million of the 2014 Notes for an aggregate 64.0 million shares of our common stock and a cash payment of $11.6 million. In April 2014, holders of the 2014 Notes converted the remaining outstanding principal amount of $56.4 million into 18.6 million shares of our common stock.
	-2	In April 2013, we entered into a term loan agreement with a Korean bank pursuant to which we may borrow up to $150.0 million through April 2016 for general working capital purposes and the repayment of inter-company debt. The loan is collateralized by substantially all the land, factories and equipment located at our facilities in Korea. Principal is payable at maturity. Interest is due quarterly, at a rate of LIBOR plus 3.70% (3.93% as of June 30, 2014). As of June 30, 2014, $80.0 million was available to be borrowed.
	-3	In March 2014, we entered into a term loan agreement with a Korean bank pursuant to which we borrowed $80.0 million. The loan is collateralized by substantially all the land, factories and equipment located at our facilities in Korea. Principal is payable at maturity. Interest is due monthly, at a foreign currency funding-linked base rate plus 2.00% (3.58% as of June 30, 2014). Proceeds were used to prepay our term loan due March 2015.
	-4	In June 2012, we entered into a term loan agreement for five years with a Korean bank collateralized by substantially all the land, factories and equipment located at our facilities in Korea. Principal is payable at maturity. Interest is due quarterly, at LIBOR plus 3.90% (4.13% as of June 30, 2014). In April 2014, we prepaid $60.0 million of the outstanding balance of the term loan.
	-5	In March 2013, we entered into a loan agreement with a Korean bank pursuant to which we may borrow up to $150.0 million through September 2017. The loan is collateralized by substantially all the land, factories and equipment located at our facilities in Korea. Principal is payable in quarterly installments of $5.0 million starting in December 2014, with the remaining balance due at maturity. Interest is due quarterly, at a foreign currency funding-linked base rate plus 1.75% (3.38% as of June 30, 2014). At June 30, 2014, $140.0 million was available to be borrowed for capital expenditures.
	-6	In September 2012, Amkor Technology Taiwan Ltd, a subsidiary in Taiwan, entered into a revolving credit facility. Availability under the revolving credit facility was originally $44.0 million and subsequent availability steps down $5.0 million every six months from the original available balance. Principal is payable at maturity. As of June 30, 2014, $24.0 million was available to be drawn for general corporate purposes and capital expenditures.
	The debt of Amkor Technology, Inc. is structurally subordinated in right of payment to all existing and future debt and other liabilities of our subsidiaries. The agreements governing our indebtedness contain a number of affirmative and negative covenants which restrict our ability to pay dividends and could restrict our operations. We have never paid a dividend to our stockholders, and we do not have any present plans for doing so. We were in compliance with all of our covenants at June 30, 2014.

Pension_and_Severance_Plans

Pension and Severance Plans	6 Months Ended
	Jun. 30, 2014
Compensation and Retirement Disclosure [Abstract]	'
Pension and Severance Plans	'
	15.    Pension and Severance Plans
	Foreign Defined Benefit Pension Plans
	Our subsidiaries in Japan, Malaysia, the Philippines and Taiwan sponsor defined benefit pension plans that cover substantially all of their respective employees who are not covered by statutory plans. Charges to expense are based upon actuarial analyses. The components of net periodic pension cost for these defined benefit plans are as follows:
		For the Three Months Ended						For the Six Months Ended
		June 30,						June 30,
		2014			2013			2014			2013
		(In thousands)
	Service cost	$	1,449		$	1,399		$	2,873		$	2,873
	Interest cost	794			746			1,573			1,521
	Expected return on plan assets	(781		)	(883		)	(1,547		)	(1,794		)
	Amortization of transition obligation	—			2			75			4
	Amortization of prior service cost	50			49			99			98
	Recognized actuarial loss	16			33			33			66
	Net periodic pension cost	1,528			1,346			3,106			2,768
	Korean Severance Plan
	Our subsidiary in Korea participates in an accrued severance plan that covers employees with at least one year of service. To the extent eligible employees are terminated, our subsidiary in Korea would be required to make lump-sum severance payments on behalf of these eligible employees based on their length of service, seniority and rate of pay at the time of termination. Accrued severance benefits are estimated assuming all eligible employees were to terminate their employment at the balance sheet date. Our contributions to the National Pension Plan of the Republic of Korea are deducted from accrued severance benefit liabilities.
	The provision recorded for severance benefits for the three and six months ended June 30, 2014, was $1.2 million and $6.8 million, respectively. The provision recorded for severance benefits for the three and six months ended June 30, 2013, was $7.3 million and $12.8 million, respectively. The balance of our Korean severance obligation consists of the following:
		June 30,			December 31,
		2014			2013
		(In thousands)
	Current (Accrued expenses)	$	11,794		$	11,197
	Non-current (Pension and severance obligations)	140,484			133,935
	Total Korean severance obligation	$	152,278		$	145,132

Fair_Value_Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2014
Fair Value Disclosures [Abstract]	'
Fair Value Measurements	'
	16.    Fair Value Measurements
	The accounting framework for determining fair value includes a hierarchy for ranking the quality and reliability of the information used to measure fair value, which enables the reader of the financial statements to assess the inputs used to develop those measurements. The fair value hierarchy consists of three tiers as follows: Level 1, defined as quoted market prices in active markets for identical assets or liabilities; Level 2, defined as inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, model-based valuation techniques for which all significant assumptions are observable in the market or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities and Level 3, defined as unobservable inputs that are not corroborated by market data.
	Our assets and liabilities recorded at fair value on a recurring basis include cash equivalent money market funds and restricted cash money market funds. Cash equivalent money market funds and restricted cash money market funds are invested in U.S. money market funds and various U.S. and foreign bank operating and time deposit accounts, which are due on demand or carry a maturity date of less than three months when purchased. No restrictions have been imposed on us regarding withdrawal of balances with respect to our cash equivalents as a result of liquidity or other credit market issues affecting the money market funds we invest in or the counterparty financial institutions holding our deposits. Money market funds are valued using quoted market prices in active markets for identical assets.
	We also measure certain assets and liabilities, including property, plant and equipment, intangible assets and our investment in J-Devices, at fair value on a nonrecurring basis. For the three and six months ended June 30, 2014 and 2013, such measurements included the consideration of third party valuation reports based on a combination of market and cost approach valuation techniques. The valuation reports contained various inputs including semiconductor industry data, replacement costs, price lists and general information regarding the assets being evaluated. Nonrecurring fair value measurements related to property, plant and equipment impairments reflect the fair value of the assets at the dates the impairments were taken during the period.
	Our fair value measurements consist of the following:
		June 30,		December 31,
		2014		2013
		(In thousands)
	Recurring fair value measurements:
	Assets:
	Cash equivalent money market funds (Level 1)	$	224,307	$	300,352
	Restricted cash money market funds (Level 1)	2,681		2,681
	Nonrecurring fair value measurements:
	Long-lived assets held for use or disposal (Level 3)	$	—	$	1,055
		For the Three Months Ended				For the Six Months Ended
		June 30,				June 30,
		2014		2013		2014		2013
		(In thousands)
	Nonrecurring fair value measurements:
	Losses on long-lived assets held for use or disposal (Level 3)	$	183	$	388	$	469	$	868
	We measure the fair value of our debt for disclosure purposes. The following table presents the fair value of financial instruments that are not recorded at fair value on a recurring basis:
		June 30, 2014				December 31, 2013
		Fair		Carrying		Fair		Carrying
		Value		Value		Value		Value
		(In thousands)
	Senior notes (Level 1)	$	1,350,374	$	1,276,111	$	1,321,443	$	1,276,390
	Convertible senior subordinated notes (Level 1)	—		—		102,585		56,350
	Term loans (Level 2)	260,000		260,000		320,000		320,000
	Total debt	$	1,610,374	$	1,536,111	$	1,744,028	$	1,652,740
	The estimated fair value of our senior and convertible senior subordinated notes is based primarily on quoted market prices reported on or near the respective balance sheet dates. The estimated fair value of our term loans was calculated using a discounted cash flow analysis, which utilized market based assumptions including forward interest rates adjusted for credit risk.

Commitments_and_Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	17.    Commitments and Contingencies
	We have a letter of credit sub-facility of $25.0 million under our $150.0 million senior secured revolving credit facility that matures in June 2017. As of June 30, 2014, we had $0.3 million of standby letters of credit outstanding and had an additional $24.7 million available for letters of credit. Such standby letters of credit are used in the ordinary course of our business and are collateralized by our cash balances.
	We generally warrant that our services will be performed in a professional and workmanlike manner and in compliance with our customers' specifications. We accrue costs for known warranty issues. Historically, our warranty costs have been immaterial.
	Legal Proceedings
	We are involved in claims and legal proceedings and may become involved in other legal matters arising in the ordinary course of our business. We evaluate these claims and legal matters on a case-by-case basis to make a determination as to the impact, if any, on our business, liquidity, results of operations, financial condition or cash flows. Except as indicated below, we believe that the ultimate outcome of these claims and proceedings, individually and in the aggregate, will not have a material adverse impact to us. Our evaluation of the potential impact of these claims and legal proceedings on our business, liquidity, results of operations, financial condition or cash flows could change in the future.
	In accordance with the accounting guidance for loss contingencies, including legal proceedings, lawsuits, pending claims and other legal matters, we accrue for a loss contingency when we conclude that the likelihood of a loss is probable and the amount of the loss can be reasonably estimated. When the reasonable estimate of the loss is within a range of amounts, and no amount in the range constitutes a better estimate than any other amount, we accrue for the amount at the low end of the range. We adjust our accruals from time to time as we receive additional information, but the loss we incur may be significantly greater than or less than the amount we have accrued. We disclose loss contingencies if there is at least a reasonable possibility that a loss has been incurred. Attorney fees related to legal matters are expensed as incurred.
	Proceedings with Tessera, Inc.
	Since March 2006, we have been involved in several proceedings with Tessera Technologies, Inc. (“Tessera”) related to a license agreement (the “License Agreement”) entered into in 1996 between Tessera and our predecessor. The proceedings generally involve disputes about whether or not Amkor owes Tessera royalties under the License Agreement with respect to certain packages, the termination of the License Agreement and post-termination infringement. The main proceeding that is pending is with the International Court of Arbitration of the International Chamber of Commerce (the “ICC”) captioned Amkor Technology, Inc. v. Tessera, Inc. (the “2009 Arbitration”), which we initiated in August 2009. In that proceeding, the ICC arbitration panel has previously ruled that royalties are due to Tessera with respect to certain asserted patents and packages and that the License Agreement was terminated by Tessera as of February 17, 2011. In May 2014, and as amended in June 2014, the arbitration panel awarded Tessera $113 million plus interest for these past royalties due under the License Agreement. The award bears simple interest at 3% per annum from the date the unpaid royalties were due under the License Agreement to the date of the award and at 10% from the date of the award until paid. The other pending arbitration proceedings with Tessera include a request for arbitration by Tessera filed in May 2011 seeking undisclosed damages and a declaration that the License Agreement had been terminated, and a continuation of the 2009 proceeding related to three additional U.S. patents.
	In July 2012, Tessera filed a complaint in the U.S. District Court for the District of Delaware. The complaint seeks injunctive relief and damages with respect to Amkor's alleged infringement of one of the U.S. patents (U.S. Patent No. 6,046,076, the "'076 patent") that the arbitration panel found to be royalty bearing in the 2009 Arbitration. In November 2013, the parties agreed to stay the Delaware litigation, which stay expired with the May 2014 award. In May 2014, Amkor moved the Delaware court to vacate the arbitration panel's award on the ground that the arbitration panel exceeded its powers in granting the award and on other grounds. The motion is pending.
	In February 2013, we filed a petition in the Superior Court for San Francisco County to vacate or correct a portion of the arbitration panel’s interim order relating to the panel’s authority to award royalties for the period after the termination of the License Agreement. The Superior Court has denied our request and we have appealed that decision to the California First District Court of Appeal. In July 2014, Tessera filed a motion in the Superior Court to enforce the arbitration panel's amended June 2014 award. We intend to contest this motion. A hearing on this motion is scheduled for August 2014.
	In April 2013, we initiated an inter partes review (the “IPR”) proceeding with the Patent Trial and Appeal Board at the United States Patent and Trademark Office (“U.S. PTO”), requesting it to find certain claims of the ‘076 patent unpatentable, including the two claims we were found to practice during the 2009 Arbitration. In October 2013, the U.S. PTO determined that there is a reasonable likelihood that we will prevail in challenging those claims and certain others. A merits hearing was held in the IPR in June 2014 and a decision is pending.
	Although the arbitration panel has awarded Tessera royalties of $113 million plus interest, most of the royalties awarded to Tessera relate to Amkor's alleged use of the ‘076 patent and the period following termination of the License Agreement. The award by the arbitration panel must be confirmed by the courts before Tessera can enforce the award against Amkor, and we believe that a favorable outcome in the IPR or in the other pending proceedings may materially and adversely impact Tessera’s ability to confirm and collect on the arbitration panel's award and any other claims for damages.
	As a result of the arbitration panel's award and other recent developments, the potential impact of the IPR proceeding on the arbitration panel's award, and our position regarding potential royalties due to Tessera following the termination of the License Agreement, our estimate of the possible range of royalties due to Tessera in the 2009 Arbitration is from $11 million to $113 million (net of royalties previously paid in 2012 and excluding interest). Our accrual for these royalties was $43.3 million at June 30, 2014.
	The ultimate amount of damages and interest we may owe to Tessera in connection with the several pending proceedings could be more or less than our estimate of the possible range of royalties due in the 2009 Arbitration, and could be more or less than the amount we expect the arbitration panel to award. The final outcome of our litigation with Tessera depends upon a number of complex factors, including whether we receive a favorable ruling in the above proceedings and other factors. We may adjust our accrual as information develops or upon the issuance of new rulings. As of June 30, 2014, we have $5.4 million accrued for interest related to these royalties, and we expect to record our estimate of interest accruing with the passage of time. We strongly dispute Tessera's claims in these proceedings and intend to vigorously defend against them. However, the final outcome of these matters is uncertain, and an adverse result could have a material adverse effect on our results of operations, financial condition and cash flows.
	Amkor Technology, Inc. v. Carsem (M) Sdn Bhd, Carsem Semiconductor Sdn Bhd, and Carsem Inc.
	Since November 2003, we have been involved in several proceedings against Carsem (M) Sdn Bhd, Carsem Semiconductor Sdn Bhd, and Carsem Inc. (collectively “Carsem”) in which we alleged that Carsem has infringed on one or more of our MicroLeadFrame ("MLF") packaging technology patent claims, including an action we initiated with the U.S. International Trade Commission (the “ITC”) in Washington, D.C., under Section 337 of the Tariff Act of 1930.
	In April 2014, the ITC made a final determination that Carsem violated Section 337 of the Tariff Act and issued a limited exclusion order barring Carsem from importing into the U.S. any of its products that infringe certain of our patent claims.
	In May 2014, the parties entered into a settlement agreement to end all pending proceedings related to the dispute, and Carsem paid Amkor an agreed sum for such settlement. Under the terms of the agreement, Carsem and Amkor have granted each other non-exclusive licenses to their respective MLP and MLF patents worldwide.

Exit_Activities_and_Reductions

Exit Activities and Reductions in Force	6 Months Ended
	Jun. 30, 2014
Restructuring and Related Activities [Abstract]	'
Exit Activities and Reductions in Force	'
	18.    Reductions in Force
	As part of our ongoing efforts to improve our manufacturing operations and manage costs, we regularly evaluate our staffing levels and facility requirements compared to business needs. The following table summarizes our exit activities and reduction in force initiatives associated with these efforts. “Charges” represents the initial charge related to the exit activity. “Cash Payments” consists of the utilization of “Charges.” “Non-cash Amounts” generally consists of pension plan curtailments and settlements and foreign currency adjustments.
		Employee
		Separation Costs
		(In thousands)
	Accrual at December 31, 2013	$	—
	Charges	3,889
	Cash Payments	(3,973		)
	Non-cash Amounts	84
	Accrual at June 30, 2014	$	—
		Employee
		Separation Costs
		(In thousands)
	Accrual at December 31, 2012	$	1,607
	Charges	5,988
	Cash Payments	(7,609		)
	Non-cash Amounts	14
	Accrual at June 30, 2013	$	—
	During the three and six months ended June 30, 2014 and 2013, we reduced our workforce through workforce reduction programs. During the three and six months ended June 30, 2014, we recorded $2.5 million and $3.9 million in charges, respectively. During the three and six months ended June 30, 2013, we recorded $2.0 million and $6.0 million, respectively.
	All charges related primarily to cost of sales.

Interim_Financial_Statements_P

Interim Financial Statements (Policies)	6 Months Ended
	Jun. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Basis of Presentation	'
	The Consolidated Financial Statements and related disclosures as of June 30, 2014, and for the three and six months ended June 30, 2014 and 2013, are unaudited, pursuant to the rules and regulations of the United States Securities and Exchange Commission (“SEC”). The December 31, 2013, Consolidated Balance Sheet data was derived from audited financial statements, but does not include all disclosures required by accounting principles generally accepted in the United States of America (“U.S.”). Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) have been condensed or omitted pursuant to such rules and regulations. In our opinion, these financial statements include all adjustments (consisting only of normal recurring adjustments) necessary for the fair statement of the results for the interim periods. These financial statements should be read in conjunction with the financial statements included in our Annual Report for the year ended December 31, 2013, filed on Form 10-K with the SEC on February 28, 2014. The results of operations for the three and six months ended June 30, 2014, are not necessarily indicative of the results to be expected for the full year. Unless the context otherwise requires, all references to “Amkor,” “we,” “us,” “our” or the “company” are to Amkor Technology, Inc. and our subsidiaries.
	On June 30, 2014, we completed the sale of our Japanese subsidiary to J-Devices, our 60% owned equity-method joint venture in Japan. The financial results of the entity were included in our consolidated financial statements up to the date of sale (Note 4). On July 31, 2013, we completed the purchase of Toshiba Electronics Malaysia Sdn. Bhd. The financial results of the entity have been included in our Consolidated Financial Statements from the date of acquisition (Note 3).
	The U.S. dollar is our reporting currency and the functional currency for our foreign subsidiaries. Effective June 30, 2014, we changed the functional currency for our sales office in Japan to the U.S. dollar primarily due to an increase in the mix of our U.S. dollar denominated sales. The change in functional currency is applied on a prospective basis.
	Beginning with the year ended December 31, 2013, we reclassified equity in earnings of unconsolidated affiliate from other expense (income) to below income tax expense in our Consolidated Statements of Income for all periods presented. The reclassification had no impact on net income.
Use of Estimates	'
	The Consolidated Financial Statements have been prepared in conformity with U.S. GAAP, using management’s best estimates and judgments where appropriate. These estimates and judgments affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements. The estimates and judgments will also affect the reported amounts for certain revenues and expenses during the reporting period. Actual results could differ materially from these estimates and judgments.

ShareBased_Compensation_Plans_

Share-Based Compensation Plans (Tables)	6 Months Ended
	Jun. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Employee service share based compensation allocation of recognized period	'
	The following table presents share-based compensation expense attributable to stock options and restricted shares.
		For the Three Months Ended								For the Six Months Ended
		June 30,								June 30,
		2014				2013				2014			2013
		(In thousands)
	Stock options	$	386			$	151			$	777		$	255
	Restricted shares	489				497				1,070			927
	Total share-based compensation expense	$	875			$	648			$	1,847		$	1,182
	The following table presents share-based compensation expense as included in the Consolidated Statements of Income:
		For the Three Months Ended								For the Six Months Ended
		June 30,								June 30,
		2014				2013				2014			2013
		(In thousands)
	Selling, general and administrative	$	764			$	565			1,613			1,030
	Research and development	111				83				234			152
	Total share-based compensation expense	$	875			$	648			$	1,847		$	1,182
Summary of all common stock option activity	'
	The following table summarizes our stock option activity for the six months ended June 30, 2014:
		Number of			Weighted Average				Weighted Average		Aggregate
		Shares			Exercise Price				Remaining		Intrinsic
		(In thousands)			Per Share				Contractual		Value
									Term (Years)		(In thousands)
	Outstanding at December 31, 2013	4,873			$	6.52
	Granted	260			7.64
	Exercised	(747	)		6.46
	Forfeited or expired	(340	)		12.3
	Outstanding at June 30, 2014	4,046			$	6.12			6.58		$	20,566
	Fully vested at June 30, 2014 and expected to vest thereafter	4,015			$	6.13			6.56		$	20,373
	Exercisable at June 30, 2014	1,955			$	7.55			3.84		$	7,197
Assumptions used in valuing the weighted average fair values of the options granted	'
	The following assumptions were used to calculate the weighted average fair values of the options granted:
		For the Three Months Ended								For the Six Months Ended
		June 30,								June 30,
		2014				2013				2014			2013
	Expected life (in years)	6				6.2				6.1			6.2
	Risk-free interest rate	2		%		1		%		2		%	1		%
	Volatility	57		%		60		%		58		%	60		%
	Dividend yield	—				—				—			—
	Weighted average grant date fair value per option granted	$	5.01			$	2.53			$	4.2		$	2.53
Restricted share activity	'
	The following table summarizes our restricted share activity for the six months ended June 30, 2014:
		Number of			Weighted
		Shares			Average
		(In thousands)			Grant-Date
					Fair Value
					(Per share)
	Nonvested at December 31, 2013	1,172			$	4.83
	Awards granted	—			—
	Awards vested	(294	)		5.09
	Awards forfeited	(11	)		4.84
	Nonvested at June 30, 2014	867			$	4.74

Other_Income_and_Expense_Table

Other Income and Expense (Tables)	6 Months Ended
	Jun. 30, 2014
Other Income and Expenses [Abstract]	'
Schedule of Other Nonoperating Income (Expense) [Table Text Block]	'
	Other income and expense consists of the following:
		For the Three Months Ended						For the Six Months Ended
		June 30,						June 30,
		2014			2013			2014			2013
		(In thousands)
	Interest income	$	(831	)	$	(676	)	$	(1,542	)	$	(1,503	)
	Foreign currency loss, net	4,213			2,041			4,547			875
	Loss on debt retirement	622			11,619			757			11,619
	Gain on sale of subsidiary to J-Devices (Note 4)	(9,155		)	—			(9,155		)	—
	Other income, net	(548		)	(108		)	(270		)	(337		)
	Total other (income) expense, net	$	(5,699	)	$	12,876		$	(5,663	)	$	10,654

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	6 Months Ended
	Jun. 30, 2014
Earnings Per Share [Abstract]	'
Computation of basic and diluted earnings per share	'
	The following table summarizes the computation of basic and diluted EPS:
		For the Three Months Ended							For the Six Months Ended
		June 30,							June 30,
		2014				2013			2014			2013
		(In thousands, except per share data)
	Net income attributable to Amkor	$	49,521			$	29,727		$	70,154		$	43,109
	Income allocated to participating securities	(184		)		(251		)	(269		)	(374		)
	Net income available to Amkor common stockholders — basic	49,337				29,476			69,885			42,735
	Adjustment for dilutive securities on net income:
	Net income reallocated to participating securities	3				58			9			80
	Interest on 6.0% convertible notes due 2014, net of tax	132				3,609			1,039			7,626
	Net income attributable to Amkor — diluted	$	49,472			$	33,143		$	70,933		$	50,441
	Weighted average shares outstanding — basic	232,891				160,886			224,868			156,672
	Effect of dilutive securities:
	Stock options	1,115				10			609			14
	6.0% convertible notes due 2014	2,866				74,215			10,705			78,413
	Weighted average shares outstanding — diluted	236,872				235,111			236,182			235,099
	Net income attributable to Amkor per common share:
	Basic	$	0.21			$	0.18		$	0.31		$	0.27
	Diluted	0.21				0.14			0.3			0.21
Antidilutive effect of potential shares of common stock that were excluded from diluted earnings per share	'
	The following table summarizes the potential shares of common stock that were excluded from diluted EPS, because the effect of including these potential shares was antidilutive:
		For the Three Months Ended						For the Six Months Ended
		June 30,						June 30,
		2014			2013			2014		2013
		(In thousands)
	Stock options and restricted share awards	1,114			4,092			1,563		4,165

Equity_and_Accumulated_Other_C1

Equity and Accumulated Other Comprehensive Income (Tables)	6 Months Ended
	Jun. 30, 2014
Equity [Abstract]	'
Changes in equity and comprehensive income attributable to both Company and noncontrolling interests	'
	The following table reflects the changes in equity attributable to both Amkor and the noncontrolling interests:
		Attributable			Attributable to			Total
		to Amkor			Noncontrolling
					Interests
		(In thousands)
	Equity at December 31, 2013	$	953,740		$	11,200		$	964,940
	Net income	70,154			1,435			71,589
	Other comprehensive loss	(7,496		)	—			(7,496		)
	Issuance of stock through employee share-based compensation plans	4,826			—			4,826
	Treasury stock acquired through surrender of shares for tax withholding	(1,006		)	—			(1,006		)
	Share-based compensation expense	1,847			—			1,847
	Conversion of debt to common stock	56,350			—			56,350
	Equity at June 30, 2014	$	1,078,415		$	12,635		$	1,091,050
		Attributable			Attributable to			Total
		to Amkor			Noncontrolling
					Interests
		(In thousands)
	Equity at December 31, 2012	$	657,955		$	8,839		$	666,794
	Net income	43,109			986			44,095
	Other comprehensive loss	(6,934		)	—			(6,934		)
	Treasury stock acquired through surrender of shares for tax withholding	(172		)	—			(172		)
	Share-based compensation expense	1,182			—			1,182
	Exchange of debt for common stock	195,034			—			195,034
	Equity at June 30, 2013	$	890,174		$	9,825		$	899,999
Schedule of Accumulated Other Comprehensive Income	'
	The following table reflects the changes in accumulated other comprehensive income and loss, net of tax:
		Defined Benefit Pension			Foreign Currency Translation			Equity Interest in J-Devices' Other Comprehensive Income (Loss)			Total
		(In thousands)
	Accumulated other comprehensive (loss) income at	$	(1,013	)	$	11,451		$	(10,693	)	$	(255	)
	31-Dec-13
	Other comprehensive income before reclassifications	—			779			3,706			4,485
	Amounts reclassified from accumulated other comprehensive (loss) income	606			(12,587		)	—			(11,981		)
	Other comprehensive income (loss)	606			(11,808		)	3,706			(7,496		)
	Accumulated other comprehensive loss at	$	(407	)	$	(357	)	$	(6,987	)	$	(7,751	)
	30-Jun-14
		Defined Benefit Pension			Foreign Currency Translation			Equity Interest in J-Devices' Other Comprehensive Income (Loss)			Total
		(In thousands)
	Accumulated other comprehensive (loss) income at	$	(5,373	)	$	16,346		$	268		$	11,241
	31-Dec-12
	Other comprehensive loss before reclassifications	—			(3,100		)	(4,051		)	(7,151		)
	Amounts reclassified from accumulated other comprehensive (loss) income	217			—			—			217
	Other comprehensive income (loss)	217			(3,100		)	(4,051		)	(6,934		)
	Accumulated other comprehensive (loss) income at	$	(5,156	)	$	13,246		$	(3,783	)	$	4,307
	30-Jun-13

Inventories_Tables

Inventories (Tables)	6 Months Ended
	Jun. 30, 2014
Inventory Disclosure [Abstract]	'
Inventories	'
	Inventories consist of the following:
		June 30,		December 31, 2013
		2014
		(In thousands)
	Raw materials and purchased components	$	147,280	$	147,292
	Work-in-process	58,388		53,131
	Total inventories	$	205,668	$	200,423

Property_Plant_and_Equipment_T

Property, Plant and Equipment (Tables)	6 Months Ended
	Jun. 30, 2014
Property, Plant and Equipment [Abstract]	'
Summary of Property, plant and equipment	'
	Property, plant and equipment consist of the following:
		June 30,			December 31, 2013
		2014
		(In thousands)
	Land	$	207,986		$	208,048
	Land use rights	26,845			26,845
	Buildings and improvements	919,379			911,258
	Machinery and equipment	3,748,385			3,577,045
	Software and computer equipment	206,247			193,641
	Furniture, fixtures and other equipment	15,453			17,430
	Construction in progress	48,430			27,039
	Total property, plant and equipment	5,172,725			4,961,306
	Less accumulated depreciation and amortization	(3,018,907		)	(2,954,753		)
	Total property, plant and equipment, net	$	2,153,818		$	2,006,553
Schedule of depreciation expense	'
	The following table presents depreciation expense as included in the Consolidated Statements of Income:
		For the Three Months Ended						For the Six Months Ended
		June 30,						June 30,
		2014			2013			2014		2013
		(In thousands)
	Cost of sales	$	101,594		$	90,805		$	201,361	$	179,973
	Selling, general and administrative	3,926			3,860			7,362		7,995
	Research and development	6,240			3,114			11,073		6,109
	Total depreciation expense	$	111,760		$	97,779		$	219,796	$	194,077

Investments_Tables

Investments (Tables)	6 Months Ended
	Jun. 30, 2014
Investments, All Other Investments [Abstract]	'
Investments	'
	Investments consist of the following:
		June 30,				December 31,
		2014				2013
		Carrying		Ownership		Carrying		Ownership
		Value		Interest		Value		Interest
		(In thousands)				(In thousands)
	Investment in unconsolidated affiliate	$	134,717	60	%	$	105,214	60	%

Accrued_Expenses_Tables

Accrued Expenses (Tables)	6 Months Ended
	Jun. 30, 2014
Payables and Accruals [Abstract]	'
Summarized Accrued expenses	'
	Accrued expenses consist of the following:
		June 30,		December 31,
		2014		2013
		(In thousands)
	Payroll and benefits	$	69,629	$	75,909
	Deferred revenue and customer advances	52,822		44,764
	Accrued royalties (Note 17)	43,324		43,324
	Accrued interest	21,369		21,807
	Income taxes payable	17,117		17,528
	Accrued severance plan obligations (Note 15)	11,794		11,197
	Acquisition payable (Note 3)	—		17,897
	Other accrued expenses	35,993		31,826
	Total accrued expenses	$	252,048	$	264,252

Debt_Tables

Debt (Tables)	6 Months Ended
	Jun. 30, 2014
Debt Disclosure [Abstract]	'
Summary of Short term Borrowings And Long term Debt	'
	Following is a summary of short-term borrowings and long-term debt:
		June 30,			December 31,
		2014			2013
		(In thousands)
	Debt of Amkor Technology, Inc.:
	Senior secured credit facilities:
	$150 million revolving credit facility, LIBOR plus 1.5%-2.25%, due June 2017	$	—		$	—
	Senior notes:
	7.375% Senior notes, due May 2018	345,000			345,000
	6.625% Senior notes, due June 2021, $75 million related party	400,000			400,000
	6.375% Senior notes, due October 2022	525,000			525,000
	Senior subordinated notes:
	6.0% Convertible senior subordinated notes, due April 2014 (1)	—			56,350
	Debt of subsidiaries:
	Amkor Technology Korea, Inc.:
	$41 million revolving credit facility, foreign currency funding-linked base rate plus 2.00%, due June 2016	—			—
	Term loan, LIBOR plus 3.70%, due June 2016 (2)	70,000			70,000
	Term loan, foreign currency funding-linked base rate plus 2.00%, due March 2017 (3)	80,000			—
	Term loan, LIBOR plus 3.90% or 3.94%, due July 2017 (4)	30,000			90,000
	Term loan, foreign currency funding-linked base rate plus 1.75%, due September 2017 (5)	10,000			10,000
	Term loan, LIBOR plus 3.70%, due December 2019	70,000			70,000
	Term loan, foreign currency funding-linked base rate plus 2.30%, due March 2015 (3)	—			80,000
	Other:
	Revolving credit facility, TAIFX plus a bank-determined spread, due April 2015 (Taiwan) (6)	—			—
		1,530,000			1,646,350
	Add: Unamortized premium	6,111			6,390
	Less: Short-term borrowings and current portion of long-term debt	(10,000		)	(61,350		)
	Long-term debt (including related party)	$	1,526,111		$	1,591,390
	-1	In April 2009, we issued $250.0 million of our 6.0% Convertible senior subordinated notes due April 2014 (the “2014 Notes”). The 2014 Notes were convertible at any time prior to the maturity date into our common stock at a price of approximately $3.02 per share, subject to adjustment. In June 2013, we completed a tender offer for the 2014 Notes and exchanged $193.7 million of the 2014 Notes for an aggregate 64.0 million shares of our common stock and a cash payment of $11.6 million. In April 2014, holders of the 2014 Notes converted the remaining outstanding principal amount of $56.4 million into 18.6 million shares of our common stock.
	-2	In April 2013, we entered into a term loan agreement with a Korean bank pursuant to which we may borrow up to $150.0 million through April 2016 for general working capital purposes and the repayment of inter-company debt. The loan is collateralized by substantially all the land, factories and equipment located at our facilities in Korea. Principal is payable at maturity. Interest is due quarterly, at a rate of LIBOR plus 3.70% (3.93% as of June 30, 2014). As of June 30, 2014, $80.0 million was available to be borrowed.
	-3	In March 2014, we entered into a term loan agreement with a Korean bank pursuant to which we borrowed $80.0 million. The loan is collateralized by substantially all the land, factories and equipment located at our facilities in Korea. Principal is payable at maturity. Interest is due monthly, at a foreign currency funding-linked base rate plus 2.00% (3.58% as of June 30, 2014). Proceeds were used to prepay our term loan due March 2015.
	-4	In June 2012, we entered into a term loan agreement for five years with a Korean bank collateralized by substantially all the land, factories and equipment located at our facilities in Korea. Principal is payable at maturity. Interest is due quarterly, at LIBOR plus 3.90% (4.13% as of June 30, 2014). In April 2014, we prepaid $60.0 million of the outstanding balance of the term loan.
	-5	In March 2013, we entered into a loan agreement with a Korean bank pursuant to which we may borrow up to $150.0 million through September 2017. The loan is collateralized by substantially all the land, factories and equipment located at our facilities in Korea. Principal is payable in quarterly installments of $5.0 million starting in December 2014, with the remaining balance due at maturity. Interest is due quarterly, at a foreign currency funding-linked base rate plus 1.75% (3.38% as of June 30, 2014). At June 30, 2014, $140.0 million was available to be borrowed for capital expenditures.
	-6	In September 2012, Amkor Technology Taiwan Ltd, a subsidiary in Taiwan, entered into a revolving credit facility. Availability under the revolving credit facility was originally $44.0 million and subsequent availability steps down $5.0 million every six months from the original available balance. Principal is payable at maturity. As of June 30, 2014, $24.0 million was available to be drawn for general corporate purposes and capital expenditures.

Pension_and_Severance_Plans_Ta

Pension and Severance Plans (Tables)	6 Months Ended
	Jun. 30, 2014
Compensation and Retirement Disclosure [Abstract]	'
Components of net periodic pension cost	'
	The components of net periodic pension cost for these defined benefit plans are as follows:
		For the Three Months Ended						For the Six Months Ended
		June 30,						June 30,
		2014			2013			2014			2013
		(In thousands)
	Service cost	$	1,449		$	1,399		$	2,873		$	2,873
	Interest cost	794			746			1,573			1,521
	Expected return on plan assets	(781		)	(883		)	(1,547		)	(1,794		)
	Amortization of transition obligation	—			2			75			4
	Amortization of prior service cost	50			49			99			98
	Recognized actuarial loss	16			33			33			66
	Net periodic pension cost	1,528			1,346			3,106			2,768
Schedule of Korean severance obligation	'
	The balance of our Korean severance obligation consists of the following:
		June 30,			December 31,
		2014			2013
		(In thousands)
	Current (Accrued expenses)	$	11,794		$	11,197
	Non-current (Pension and severance obligations)	140,484			133,935
	Total Korean severance obligation	$	152,278		$	145,132

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2014
Fair Value Disclosures [Abstract]	'
Schedule of recurring and nonrecurring fair value measurements	'
	Our fair value measurements consist of the following:
		June 30,		December 31,
		2014		2013
		(In thousands)
	Recurring fair value measurements:
	Assets:
	Cash equivalent money market funds (Level 1)	$	224,307	$	300,352
	Restricted cash money market funds (Level 1)	2,681		2,681
	Nonrecurring fair value measurements:
	Long-lived assets held for use or disposal (Level 3)	$	—	$	1,055
		For the Three Months Ended				For the Six Months Ended
		June 30,				June 30,
		2014		2013		2014		2013
		(In thousands)
	Nonrecurring fair value measurements:
	Losses on long-lived assets held for use or disposal (Level 3)	$	183	$	388	$	469	$	868
Schedule of fair value of debt	'
	The following table presents the fair value of financial instruments that are not recorded at fair value on a recurring basis:
		June 30, 2014				December 31, 2013
		Fair		Carrying		Fair		Carrying
		Value		Value		Value		Value
		(In thousands)
	Senior notes (Level 1)	$	1,350,374	$	1,276,111	$	1,321,443	$	1,276,390
	Convertible senior subordinated notes (Level 1)	—		—		102,585		56,350
	Term loans (Level 2)	260,000		260,000		320,000		320,000
	Total debt	$	1,610,374	$	1,536,111	$	1,744,028	$	1,652,740

Exit_Activities_and_Reductions1

Exit Activities and Reductions in Force (Tables)	6 Months Ended
	Jun. 30, 2014
Restructuring and Related Activities [Abstract]	'
Summary of exit activities and reduction in force initiatives	'
	The following table summarizes our exit activities and reduction in force initiatives associated with these efforts. “Charges” represents the initial charge related to the exit activity. “Cash Payments” consists of the utilization of “Charges.” “Non-cash Amounts” generally consists of pension plan curtailments and settlements and foreign currency adjustments.
		Employee
		Separation Costs
		(In thousands)
	Accrual at December 31, 2013	$	—
	Charges	3,889
	Cash Payments	(3,973		)
	Non-cash Amounts	84
	Accrual at June 30, 2014	$	—
		Employee
		Separation Costs
		(In thousands)
	Accrual at December 31, 2012	$	1,607
	Charges	5,988
	Cash Payments	(7,609		)
	Non-cash Amounts	14
	Accrual at June 30, 2013	$	—

Business_Acquisitions_Details

Business Acquisitions (Details) (ToshibaElectronicsMalaysia [Member])	1 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Jul. 31, 2013	Jul. 31, 2013
	USD ($)	USD ($)	JPY (¥)
Business Acquisition [Line Items]	'	'	'
Business Acquisition, Percentage of Voting Interests Acquired	'	100.00%	100.00%
Business Combination, Consideration Transferred	'	$61.20	'
Business Acquisition, Cost of Acquired Entity, Cash Paid	18.8	42.4	'
Cap on Future Royalty Payments	'	$15	¥ 1,500

Sale_of_Subsidiary_of_JDevices1

Sale of Subsidiary of J-Devices (Details)

3 Months Ended

6 Months Ended

3 Months Ended

6 Months Ended

1 Months Ended

3 Months Ended

6 Months Ended

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2014

Dec. 31, 2013

Apr. 30, 2013

Mar. 31, 2013

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

USD ($)

USD ($)

USD ($)

USD ($)

J-Devices [Member]

J-Devices [Member]

J-Devices [Member]

J-Devices [Member]

J-Devices [Member]

Amkor Iwate Company Ltd [Member]

Amkor Iwate Company Ltd [Member]

Amkor Iwate Company Ltd [Member]

Amkor Iwate Company Ltd [Member]

USD ($)

USD ($)

USD ($)

JPY (¥)

USD ($)

USD ($)

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

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'

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'

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'

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'

'

'

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Sale of Stock, Percentage of Ownership before Transaction

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'

'

'

'

'

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'

100.00%

100.00%

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Equity Method Investment, Ownership Percentage

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'

'

60.00%

60.00%

60.00%

60.00%

30.00%

'

'

'

'

Sale of Stock, Consideration Received on Transaction

'

'

'

'

'

'

'

'

'

$11,100,000

¥ 1,100,000,000

'

'

Proceeds from Divestiture of Interest in Consolidated Subsidiaries

'

'

'

'

'

'

'

'

'

1,000,000

100,000,000

'

'

Sale of Subsidiary - Remaining Cash to Be Received

'

'

'

'

'

'

'

'

'

10,100,000

1,000,000,000

'

'

Gain on sale of subsidiary to J-Devices

9,155,000

0

9,155,000

0

'

'

'

'

'

'

'

9,155,000

'

Disposal Group, Including Discontinued Operation, Foreign Currency Translation Gains (Losses)

'

'

'

'

'

'

'

'

'

'

'

12,600,000

'

Business Combination, Bargain Purchase, Gain Recognized, Amount

'

'

'

'

14,700,000

'

'

'

'

'

'

'

'

Income (Loss) from Equity Method Investments

20,036,000

1,445,000

25,797,000

1,500,000

8,800,000

8,800,000

'

'

'

'

'

'

'

Combined Net Gain from Sale of Subsidiary

'

'

'

'

'

'

'

'

'

'

'

$18,000,000

$18,000,000

ShareBased_Compensation_Plans_1

Share-Based Compensation Plans Compensation Expense (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Share-based compensation expense	$875	$648	$1,847	$1,182
Selling, General and Administrative Expense [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Share-based compensation expense	764	565	1,613	1,030
Research and Development Expense [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Share-based compensation expense	111	83	234	152
Stock options [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Share-based compensation expense	386	151	777	255
Restricted shares [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Share-based compensation expense	$489	$497	$1,070	$927

ShareBased_Compensation_Plans_2

Share-Based Compensation Plans Stock Options (Details) (Stock options [Member], USD $)	6 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2014
Stock options [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Number of shares outstanding beginning balance	4,873
Weighted average exercise price per share outstanding beginning balance	$6.52
Number of shares granted	260
Weighted average exercise price per share granted	$7.64
Number of shares exercised	-747
Weighted average exercise price per share exercised	$6.46
Number of shares forfeited or expired	-340
Weighted average exercise price per share forfeited or expired	$12.30
Number of shares outstanding ending balance	4,046
Weighted average exercise price per share outstanding ending balance	$6.12
Weighted average exercise price per share average contractual term (years)	'6 years 6 months 29 days
Aggregate intrinsic value outstanding ending balance (in dollars)	$20,566
Number of shares fully vested and expected to vest	4,015
Weighted average exercise price per share fully vested and expected to vest	$6.13
Weighted average remaining contractual term fully vested and expected to vest (years)	'6 years 6 months 22 days
Aggregate intrinsic value fully vested and expected to vest (in dollars)	20,373
Number of shares exercisable	1,955
Weighted average exercise price per share exercisable	$7.55
Weighted average remaining contractual term exercisable (years)	'3 years 10 months 2 days
Aggregate intrinsic value exercisable (in dollars)	$7,197

ShareBased_Compensation_Plans_3

Share-Based Compensation Plans Weighted Average Fair Value (Details) (Stock options [Member], USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Stock options [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Expected life (in years)	'6 years	'6 years 2 months 12 days	'6 years 1 month 6 days	'6 years 2 months 12 days
Risk-free interest rate	2.00%	1.00%	2.00%	1.00%
Volatility	57.00%	60.00%	58.00%	60.00%
Dividend yield	0.00%	0.00%	0.00%	0.00%
Weighted average grant date fair value per option granted (in dollars per share)	$5.01	$2.53	$4.20	$2.53

ShareBased_Compensation_Plans_4

Share-Based Compensation Plans Restricted Shares (Details) (Restricted shares [Member], USD $)	6 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2014
Restricted shares [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Number of shares nonvested beginning balance	1,172
Weighted average grant-date fair value nonvested beginning balance (in dollars per share)	$4.83
Number of shares awards granted	0
Weighted average grant-date fair value awards granted (in dollars per share)	$0
Number of shares awards vested	-294
Weighted average grant-date fair value awards vested (in dollars per share)	$5.09
Number of shares awards forfeited	-11
Weighted average grant-date fair value awards forfeited (in dollars per share)	$4.84
Number of shares nonvested ending balance	867
Weighted average grant-date fair value nonvested ending balance (in dollars per share)	$4.74

ShareBased_Compensation_Plans_5

Share-Based Compensation Plans Textuals (Details) (USD $)	6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014
Stock options [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Unrecognized compensation expense from share-based compensation awards	$4.80
Weighted-average period of recognition of unrecognized compensation expense (in years)	'3 years
Restricted shares [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Unrecognized compensation expense from share-based compensation awards	$3.40
Weighted-average period of recognition of unrecognized compensation expense (in years)	'2 years 6 months

Other_Income_and_Expense_Detai

Other Income and Expense (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Other Income and Expenses [Abstract]	'	'	'	'
Interest income	($831)	($676)	($1,542)	($1,503)
Foreign currency loss, net	4,213	2,041	4,547	875
Loss on debt retirement	622	11,619	757	11,619
Gain on sale of subsidiary to J-Devices (Note 4)	-9,155	0	-9,155	0
Other income, net	-548	-108	-270	-337
Total other (income) expense, net	($5,699)	$12,876	($5,663)	$10,654

Income_Taxes_Details

Income Taxes (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Income Tax Disclosure [Abstract]	'	'	'	'
Income tax expense	$12,511	($10,238)	$17,440	($6,209)

Income_Taxes_Unrecognized_Tax_

Income Taxes Unrecognized Tax Benefits (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Unrecognized Tax Benefits [Abstract]	'	'
Gross unrecognized tax benefits	$6.90	$27.10

Earnings_Per_Share_Details

Earnings Per Share (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Apr. 30, 2009
Dilutive Securities Adjustments [Line Items]	'	'	'	'	'
Net income attributable to Amkor	$49,521	$29,727	$70,154	$43,109	'
Income allocated to participating securities	-184	-251	-269	-374	'
Net income available to Amkor common stockholders — basic	49,337	29,476	69,885	42,735	'
Adjustment for dilutive securities on net income:	'	'	'	'	'
Net income reallocated to participating securities	3	58	9	80	'
Net income attributable to Amkor — diluted	49,472	33,143	70,933	50,441	'
Weighted average shares outstanding — basic	232,891	160,886	224,868	156,672	'
Effect of dilutive securities:	'	'	'	'	'
Stock options	1,115	10	609	14	'
Weighted average shares outstanding — diluted	236,872	235,111	236,182	235,099	'
Net income attributable to Amkor per common share:	'	'	'	'	'
Basic (in dollars per share)	$0.21	$0.18	$0.31	$0.27	'
Diluted (in dollars per share)	$0.21	$0.14	$0.30	$0.21	'
Convertible Senior Subordinated Notes Due April 2014 [Member]	'	'	'	'	'
Adjustment for dilutive securities on net income:	'	'	'	'	'
Interest on 6.0% convertible notes due 2014, net of tax	$132	$3,609	$1,039	$7,626	'
Effect of dilutive securities:	'	'	'	'	'
6.0% convertible notes due 2014	2,866	74,215	10,705	78,413	'
Net income attributable to Amkor per common share:	'	'	'	'	'
Interest rate on convertible notes due 2014	6.00%	6.00%	6.00%	6.00%	6.00%

Earnings_Per_Share_Antidilutiv

Earnings Per Share Antidilutive (Details) (Stock Options And Restricted Shares [Member])	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Stock Options And Restricted Shares [Member]	'	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'	'
Stock options and restricted share awards	1,114	4,092	1,563	4,165

Equity_and_Accumulated_Other_C2

Equity and Accumulated Other Comprehensive Income (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Schedule of Stockholders Equity and Comprehensive Income [Line Items]	'	'	'	'
Equity, Beginning balance	'	'	$964,940	$666,794
Net income	50,406	30,329	71,589	44,095
Other comprehensive income (loss)	-11,445	-2,824	-7,496	-6,934
Issuance of stock through employee share-based compensation plans	'	'	4,826	'
Treasury stock acquired through surrender of shares for tax withholding	'	'	-1,006	-172
Share-based compensation expense	'	'	1,847	1,182
Conversion of debt to common stock	'	'	56,350	'
Exchange of debt for common stock	'	'	'	195,034
Equity, Ending balance	1,091,050	899,999	1,091,050	899,999
Amkor [Member]	'	'	'	'
Schedule of Stockholders Equity and Comprehensive Income [Line Items]	'	'	'	'
Equity, Beginning balance	'	'	953,740	657,955
Net income	'	'	70,154	43,109
Other comprehensive income (loss)	'	'	-7,496	-6,934
Issuance of stock through employee share-based compensation plans	'	'	4,826	'
Treasury stock acquired through surrender of shares for tax withholding	'	'	-1,006	-172
Share-based compensation expense	'	'	1,847	1,182
Conversion of debt to common stock	'	'	56,350	'
Exchange of debt for common stock	'	'	'	195,034
Equity, Ending balance	1,078,415	890,174	1,078,415	890,174
Noncontrolling Interest [Member]	'	'	'	'
Schedule of Stockholders Equity and Comprehensive Income [Line Items]	'	'	'	'
Equity, Beginning balance	'	'	11,200	8,839
Net income	'	'	1,435	986
Other comprehensive income (loss)	'	'	0	0
Issuance of stock through employee share-based compensation plans	'	'	0	'
Treasury stock acquired through surrender of shares for tax withholding	'	'	0	0
Share-based compensation expense	'	'	0	0
Conversion of debt to common stock	'	'	0	'
Exchange of debt for common stock	'	'	'	0
Equity, Ending balance	$12,635	$9,825	$12,635	$9,825

Equity_and_Accumulated_Other_C3

Equity and Accumulated Other Comprehensive Income Accumulated Other Comprehensive Income (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'
Accumulated other comprehensive (loss) income, beginning balance	'	'	($255)	$11,241
Other comprehensive income (loss) before reclassifications	'	'	4,485	-7,151
Amounts reclassified from accumulated other comprehensive (loss) income	'	'	-11,981	217
Total other comprehensive loss	-11,445	-2,824	-7,496	-6,934
Accumulated other comprehensive (loss) income, ending balance	-7,751	4,307	-7,751	4,307
Defined Benefit Pension [Member]	'	'	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'
Accumulated other comprehensive (loss) income, beginning balance	'	'	-1,013	-5,373
Other comprehensive income (loss) before reclassifications	'	'	0	0
Amounts reclassified from accumulated other comprehensive (loss) income	'	'	606	217
Total other comprehensive loss	'	'	606	217
Accumulated other comprehensive (loss) income, ending balance	-407	-5,156	-407	-5,156
Foreign Currency Translation [Member]	'	'	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'
Accumulated other comprehensive (loss) income, beginning balance	'	'	11,451	16,346
Other comprehensive income (loss) before reclassifications	'	'	779	-3,100
Amounts reclassified from accumulated other comprehensive (loss) income	'	'	-12,587	0
Total other comprehensive loss	'	'	-11,808	-3,100
Accumulated other comprehensive (loss) income, ending balance	-357	13,246	-357	13,246
Equity Interest in J-Devices' Other Comprehensive Income (Loss) [Member]	'	'	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'
Accumulated other comprehensive (loss) income, beginning balance	'	'	-10,693	268
Other comprehensive income (loss) before reclassifications	'	'	3,706	-4,051
Amounts reclassified from accumulated other comprehensive (loss) income	'	'	0	0
Total other comprehensive loss	'	'	3,706	-4,051
Accumulated other comprehensive (loss) income, ending balance	($6,987)	($3,783)	($6,987)	($3,783)

Inventories_Details

Inventories (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Inventories	'	'
Raw materials and purchased components	$147,280	$147,292
Work-in-process	58,388	53,131
Total inventories	$205,668	$200,423

Property_Plant_and_Equipment_D

Property, Plant and Equipment (Details) (USD $)

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Land [Member]

Land [Member]

Land use rights [Member]

Land use rights [Member]

Buildings and improvements [Member]

Buildings and improvements [Member]

Machinery and equipment [Member]

Machinery and equipment [Member]

Software and computer equipment [Member]

Software and computer equipment [Member]

Furniture, fixtures and other equipment [Member]

Furniture, fixtures and other equipment [Member]

Construction in progress [Member]

Construction in progress [Member]

KOREA, REPUBLIC OF

Property, Plant and Equipment [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Property, plant and equipment, gross

$5,172,725,000

$4,961,306,000

$207,986,000

$208,048,000

$26,845,000

$26,845,000

$919,379,000

$911,258,000

$3,748,385,000

$3,577,045,000

$206,247,000

$193,641,000

$15,453,000

$17,430,000

$48,430,000

$27,039,000

'

Less accumulated depreciation and amortization

-3,018,907,000

-2,954,753,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Total property, plant and equipment, net

2,153,818,000

2,006,553,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Interest Costs Capitalized

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$5,100,000

Property_Plant_and_Equipment_D1

Property, Plant and Equipment Depreciation Expense (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Schedule of depreciation expense [Line Items]	'	'	'	'
Total depreciation expense	$111,760	$97,779	$219,796	$194,077
Cost of Sales [Member]	'	'	'	'
Schedule of depreciation expense [Line Items]	'	'	'	'
Total depreciation expense	101,594	90,805	201,361	179,973
Selling, General and Administrative Expense [Member]	'	'	'	'
Schedule of depreciation expense [Line Items]	'	'	'	'
Total depreciation expense	3,926	3,860	7,362	7,995
Research and Development Expense [Member]	'	'	'	'
Schedule of depreciation expense [Line Items]	'	'	'	'
Total depreciation expense	$6,240	$3,114	$11,073	$6,109

Investments_Details

Investments (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013	Apr. 30, 2013	Mar. 31, 2013
In Thousands, unless otherwise specified
Schedule of Equity Method Investments [Line Items]	'	'	'	'
Carrying value	$134,717	$105,214	'	'
J-Devices [Member]	'	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'	'
Carrying value	$134,717	$105,214	'	'
Ownership interest	60.00%	60.00%	60.00%	30.00%

Investments_Narrative_Details

Investments Narrative (Details) (J-Devices [Member], USD $)	1 Months Ended
In Millions, unless otherwise specified	Apr. 30, 2013	Oct. 31, 2009	Jun. 30, 2014	Dec. 31, 2013	Mar. 31, 2013
Schedule of Equity Method Investments [Line Items]	'	'	'	'	'
Ownership interest	60.00%	'	60.00%	60.00%	30.00%
Payments to acquire equity method investments (in dollars and yen)	$67.40	$16.70	'	'	'
Ownership Threshold 2014 [Member]	'	'	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'	'	'
Maximum ownership ratio of call options	'	'	66.00%	'	'
Ownership Threshold 2015 [Member]	'	'	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'	'	'
Maximum ownership ratio of call options	'	'	80.00%	'	'
Minimum ownership threshold, put option	'	'	80.00%	'	'
Amkor [Member]	'	'	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'	'	'
Ownership interest	'	'	60.00%	'	'
Former NMD Shareholders [Member]	'	'	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'	'	'
Ownership interest	'	'	34.00%	'	'
Toshiba [Member]	'	'	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'	'	'
Ownership interest	'	'	6.00%	'	'

Accrued_Expenses_Details

Accrued Expenses (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Payables and Accruals [Abstract]	'	'
Payroll and benefits	$69,629	$75,909
Deferred revenue and customer advances	52,822	44,764
Accrued royalties (Note 17)	43,324	43,324
Accrued interest	21,369	21,807
Income taxes payable	17,117	17,528
Accrued severance plan obligations (Note 15)	11,794	11,197
Acquisition payable (Note 3)	0	17,897
Other accrued expenses	35,993	31,826
Total accrued expenses	$252,048	$264,252

Debt_Long_Term_Debt_Details

Debt Long Term Debt (Details) (USD $)

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Apr. 30, 2009

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Mar. 31, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

In Thousands, unless otherwise specified

Senior Notes Due May 2018 [Member]

Senior Notes Due May 2018 [Member]

Senior Notes Due June 2021 [Member]

Senior Notes Due June 2021 [Member]

Senior Notes Due October 2022 [Member]

Senior Notes Due October 2022 [Member]

Convertible Senior Subordinated Notes Due April 2014 [Member]

Convertible Senior Subordinated Notes Due April 2014 [Member]

Convertible Senior Subordinated Notes Due April 2014 [Member]

Term Loan Due June 2016 [Member]

Term Loan Due June 2016 [Member]

Term Loan Due March 2017 [Member]

Term Loan Due March 2017 [Member]

Term Loan Due March 2017 [Member]

Term Loan Due July 2017 [Member]

Term Loan Due July 2017 [Member]

Term Loan Due September 2017 [Member]

Term Loan Due September 2017 [Member]

Term Loan Due December 2019 [Member]

Term Loan Due December 2019 [Member]

Term Loan Due March 2015 [Member]

Term Loan Due March 2015 [Member]

Senior Secured Revolving Credit Facility due June 2017

Senior Secured Revolving Credit Facility due June 2017

Revolving Credit Facility Due June 2016 [Member]

Revolving Credit Facility Due June 2016 [Member]

Revolving Credit Facility Due April 2015 [Member]

Revolving Credit Facility Due April 2015 [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Taiwan Subsidiaries [Member]

Taiwan Subsidiaries [Member]

Debt Instrument [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Borrowing under credit facility

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$0

$0

$0

$0

$0

$0

Senior notes

'

'

345,000

345,000

400,000

400,000

525,000

525,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Convertible senior subordinated notes

'

'

'

'

'

'

'

'

0

56,350

250,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Subsidiary term loan

'

'

'

'

'

'

'

'

'

'

'

70,000

70,000

80,000

80,000

0

30,000

90,000

10,000

10,000

70,000

70,000

0

80,000

'

'

'

'

'

'

Long-term Debt, Gross

1,530,000

1,646,350

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Add: Unamortized premium

6,111

6,390

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Less: Short-term borrowings and current portion of long-term debt

-10,000

-61,350

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Long-term debt (including related party)

$1,526,111

$1,591,390

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt_Details

Debt (Details) (USD $)

6 Months Ended

1 Months Ended

6 Months Ended

6 Months Ended

3 Months Ended

6 Months Ended

1 Months Ended

6 Months Ended

6 Months Ended

6 Months Ended

6 Months Ended

6 Months Ended

Share data in Millions, except Per Share data, unless otherwise specified

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Apr. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Dec. 31, 2013

Apr. 30, 2009

Jun. 30, 2014

Dec. 31, 2013

Apr. 30, 2013

Jun. 30, 2014

Mar. 31, 2014

Dec. 31, 2013

Jun. 30, 2012

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Jun. 30, 2014

Mar. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Mar. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Sep. 30, 2012

Jun. 30, 2014

Senior Notes Due May 2018 [Member]

Senior Notes Due May 2018 [Member]

Senior Notes Due June 2021 [Member]

Senior Notes Due June 2021 [Member]

Senior Notes Due October 2022 [Member]

Senior Notes Due October 2022 [Member]

Convertible Senior Subordinated Notes Due April 2014 [Member]

Convertible Senior Subordinated Notes Due April 2014 [Member]

Convertible Senior Subordinated Notes Due April 2014 [Member]

Convertible Senior Subordinated Notes Due April 2014 [Member]

Convertible Senior Subordinated Notes Due April 2014 [Member]

Term Loan Due June 2016 [Member]

Term Loan Due June 2016 [Member]

Term Loan Due June 2016 [Member]

Term Loan Due March 2017 [Member]

Term Loan Due March 2017 [Member]

Term Loan Due March 2017 [Member]

Term Loan Due July 2017 [Member]

Term Loan Due July 2017 [Member]

Term Loan Due July 2017 [Member]

Term Loan Due July 2017 [Member]

Term Loan Due July 2017 [Member]

Term Loan Due September 2017 [Member]

Term Loan Due September 2017 [Member]

Term Loan Due September 2017 [Member]

Term Loan Due September 2017 [Member]

Term Loan Due December 2019 [Member]

Term Loan Due December 2019 [Member]

Term Loan Due March 2015 [Member]

Term Loan Due March 2015 [Member]

Senior Secured Revolving Credit Facility due June 2017

Senior Secured Revolving Credit Facility due June 2017

Senior Secured Revolving Credit Facility due June 2017

Revolving Credit Facility Due June 2016 [Member]

Revolving Credit Facility Due April 2015 [Member]

Revolving Credit Facility Due April 2015 [Member]

Related Party [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Korea Subsidiaries [Member]

Minimum [Member]

Maximum [Member]

Korea Subsidiaries [Member]

Taiwan Subsidiaries [Member]

Taiwan Subsidiaries [Member]

Senior Notes Due June 2021 [Member]

Maximum [Member]

Minimum [Member]

Maximum [Member]

Maximum [Member]

Debt Instrument [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Senior notes

'

'

$345,000,000

$345,000,000

$400,000,000

$400,000,000

$525,000,000

$525,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Credit facility, borrowing capacity

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

150,000,000

'

'

41,000,000

'

44,000,000

'

Repayments of Long-term Debt

140,000,000

0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

60,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument Term

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'5 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument, Periodic Payment, Principal

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

5,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt, interest rate description

'

'

'

'

'

'

'

'

'

'

'

'

'

'LIBOR plus 3.70%

'

'

'foreign currency funding-linked base rate plus 2.00%

'

'

'

' LIBOR plus 3.90% or 3.94%

'

'

'

'

'foreign currency funding-linked base rate plus 1.75%

'

'

'LIBOR plus 3.70%

'

'foreign currency funding-linked rate plus 2.30%

'

'LIBOR plus 1.5%-2.25%

'

'

'foreign currency funding-linked base rate plus 2.00%

'TAIFX plus a bank-determined spread

'

'

Debt Instrument, Interest Rate, Stated Percentage

'

'

7.38%

'

'

'

6.38%

'

'

6.00%

6.00%

'

6.00%

3.70%

'

'

2.00%

'

'

'

3.90%

'

3.90%

3.94%

'

1.75%

'

'

3.70%

'

2.30%

'

'

1.50%

2.25%

2.00%

'

'

6.63%

Debt Instrument, Convertible, Conversion Price

'

'

'

'

'

'

'

'

'

'

'

'

$3.02

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Convertible senior subordinated notes

'

'

'

'

'

'

'

'

'

'

0

56,350,000

250,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Face amount for related party

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

75,000,000

Debt Conversion, Original Debt, Amount

'

'

'

'

'

'

'

'

56,400,000

193,700,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Conversion, Converted Instrument, Shares Issued

'

'

'

'

'

'

'

'

18.6

64

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument, Unused Borrowing Capacity, Amount

'

'

'

'

'

'

'

'

'

'

'

'

'

80,000,000

'

150,000,000

'

'

'

'

'

'

'

'

'

140,000,000

'

150,000,000

'

'

'

'

'

'

'

'

'

'

'

Loans Payable

'

'

'

'

'

'

'

'

'

'

'

'

'

70,000,000

70,000,000

'

80,000,000

80,000,000

0

'

30,000,000

90,000,000

'

'

'

10,000,000

10,000,000

'

70,000,000

70,000,000

0

80,000,000

'

'

'

'

'

'

'

Payments of Debt Exchange Costs

0

11,619,000

'

'

'

'

'

'

'

11,600,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Interest rate for debt (percentage)

'

'

'

'

'

'

'

'

'

'

'

'

'

3.93%

'

'

3.58%

'

'

'

4.13%

'

'

'

'

3.38%

'

'

'

'

'

'

'

'

'

'

'

'

'

Current borrowing capacity

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

24,000,000

'

'

Line of Credit Facility, Step Down Provision

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$5,000,000

'

Pension_and_Severance_Plans_De

Pension and Severance Plans (Details) (Foreign Pension Plans [Member], USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Foreign Pension Plans [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Service cost	$1,449	$1,399	$2,873	$2,873
Interest cost	794	746	1,573	1,521
Expected return on plan assets	-781	-883	-1,547	-1,794
Amortization of transition obligation	0	2	75	4
Amortization of prior service cost	50	49	99	98
Recognized actuarial loss	16	33	33	66
Net periodic pension cost	$1,528	$1,346	$3,106	$2,768

Pension_and_Severance_Plans_Te

Pension and Severance Plans Textuals (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'	'
Non-current (Pension and severance obligations)	$159,936,000	'	$159,936,000	'	$165,073,000
Korean Severance Plan [Member]	'	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'	'
Accrued severance plan, minimum service period	'	'	'1 year	'	'
Provision for severance benefits	1,200,000	7,300,000	6,800,000	12,800,000	'
Current (Accrued expenses)	11,794,000	'	11,794,000	'	11,197,000
Non-current (Pension and severance obligations)	140,484,000	'	140,484,000	'	133,935,000
Total Korean severance obligation	$152,278,000	'	$152,278,000	'	$145,132,000

Fair_Value_Measurements_Fair_V

Fair Value Measurements Fair Value Measurements (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]	'	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'	'
Cash equivalent money market funds (Level 1)	$224,307	'	$224,307	'	$300,352
Restricted cash money market funds (Level 1)	2,681	'	2,681	'	2,681
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]	'	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'	'
Long-lived assets held for use or disposal (Level 3)	0	'	0	'	1,055
Losses on long-lived assets held for use or disposal (Level 3)	$183	$388	$469	$868	'

Fair_Value_Measurements_Fair_V1

Fair Value Measurements Fair Value of Debt (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'
Fair Value	$1,610,374	$1,744,028
Carrying Value	1,536,111	1,652,740
Senior Notes	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'
Carrying Value	1,276,111	1,276,390
Convertible Senior Subordinated Notes	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'
Carrying Value	0	56,350
Term Loans	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'
Carrying Value	260,000	320,000
Fair Value, Inputs, Level 1 [Member] | Senior Notes	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'
Fair Value	1,350,374	1,321,443
Fair Value, Inputs, Level 1 [Member] | Convertible Senior Subordinated Notes	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'
Fair Value	0	102,585
Fair Value, Inputs, Level 2 [Member] | Term Loans	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'
Fair Value	$260,000	$320,000

Commitments_and_Contingencies_

Commitments and Contingencies (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013	31-May-14	Jun. 30, 2014	Jun. 30, 2014	Jun. 30, 2014	Dec. 31, 2013	Aug. 31, 2009	Jul. 31, 2012
			Tessera Inc Legal Proceedings [Member]	Tessera Inc Legal Proceedings [Member]	Letter of Credit [Member]	Senior Secured Revolving Credit Facility due June 2017	Senior Secured Revolving Credit Facility due June 2017	2009 Arbitration [Member]	Delaware Litigation [Member]
								Tessera Inc Legal Proceedings [Member]	Tessera Inc Legal Proceedings [Member]
								patents	patents
Loss Contingencies [Line Items]	'	'	'	'	'	'	'	'	'
Credit facility, borrowing capacity	'	'	'	'	$25,000,000	$150,000,000	'	'	'
Borrowings outstanding	'	'	'	'	300,000	0	0	'	'
Credit facility, additional borrowing available	'	'	'	'	24,700,000	'	'	'	'
Loss Contingency, Damages Awarded, Value	'	'	113,000,000	'	'	'	'	'	'
Loss Contingency, Patents Allegedly Infringed, Number	'	'	'	'	'	'	'	3	1
Loss Contingency, Range of Possible Loss, Minimum	'	'	'	11,000,000	'	'	'	'	'
Loss Contingency, Range of Possible Loss, Maximum	'	'	'	113,000,000	'	'	'	'	'
Loss Contingency, Interest Rate Until Date of Award	'	'	3.00%	'	'	'	'	'	'
Loss Contingency, Interest Rate After Date of Award	'	'	10.00%	'	'	'	'	'	'
Accrued Royalties, Current	43,324,000	43,324,000	'	'	'	'	'	'	'
Accrued interest	$21,369,000	$21,807,000	'	$5,400,000	'	'	'	'	'

Exit_Activities_and_Reductions2

Exit Activities and Reductions in Force (Details) (Employee Separation Costs [Member], USD $)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013
Employee Separation Costs [Member]	'	'
Summary of exit activities and reduction in force initiatives	'	'
Accrual, Beginning balance	$0	$1,607
Charges	3,889	5,988
Cash Payments	-3,973	-7,609
Non-cash Amounts	84	14
Accrual, Ending balance	$0	$0

Exit_Activities_and_Reductions3

Exit Activities and Reductions in Force (Narrative) (Details) (Cost of Sales [Member], USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Cost of Sales [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Severance Costs	$2.50	$2	$3.90	$6