Earnings Per Share (Tables)

3 Months Ended

Mar. 31, 2017

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 March 31,
	2017			2016
	(In thousands, except per share data)
Net income (loss) available to Amkor common stockholders	$	(10,006	)	$	(875	)
Weighted-average number of common shares outstanding — basic	238,685			237,025
Weighted-average number of common shares outstanding — diluted	238,685			237,025
Net income (loss) attributable to Amkor per common share:
Basic	$	(0.04	)	$	—
Diluted	(0.04		)	—

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 anti-dilutive:

	For the Three Months Ended March 31,
	2017	2016
	(In thousands)
Stock options and restricted share awards	5,449	4,033