Earnings Per Share (Tables)

3 Months Ended

Mar. 31, 2020

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,
	2020		2019
	(In thousands, except per share data)
Net income (loss) attributable to Amkor common stockholders	$	63,889	$	(22,879	)
Weighted-average number of common shares outstanding - basic	240,919		239,414
Effect of dilutive securities:
Stock options and restricted share awards	414		—
Weighted-average number of common shares outstanding - diluted	241,333		239,414
Net income (loss) attributable to Amkor per common share:
Basic	$	0.27	$	(0.10	)
Diluted	0.26		(0.10		)

Summary of potential shares of common stock 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,
	2020	2019
	(In thousands)
Stock options and restricted share awards	4,321	7,123