Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2013

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 Year Ended December 31,
	2013			2012			2011
	(In thousands, except per share data)
Net income attributable to Amkor	$	109,296		$	41,818		$	91,808
Income allocated to participating securities	(681		)	(212		)	(332		)
Net income available to Amkor common stockholders	108,615			41,606			91,476
Adjustment for dilutive securities on net income:
Net income reallocated to participating securities	93			212			332
Interest on 6.0% convertible notes due 2014, net of tax	9,440			16,103			16,103
Net income attributable to Amkor — diluted	$	118,148		$	57,921		$	107,911
Weighted average shares outstanding — basic	187,032			160,105			190,829
Effect of dilutive securities:
Stock options and restricted share awards	21			241			199
6.0% convertible notes due 2014	48,277			82,658			82,658
Weighted average shares outstanding — diluted	235,330			243,004			273,686
Net income attributable to Amkor per common share:
Basic	$	0.58		$	0.26		$	0.48
Diluted	0.50			0.24			0.39

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 Year Ended December 31,
	2013	2012	2011
	(In thousands)
Stock options and restricted share awards	4,890	4,416	5,070
2.5% convertible notes due 2011	—	—	1,094
6.25% convertible notes due 2013	—	—	695
Total potentially dilutive shares	4,890	4,416	6,859