Calculation Of Net Income Per Share (Tables)

12 Months Ended

Dec. 31, 2018

Earnings Per Share [Abstract]

Schedule of Weighted Average Number of Shares [Table Text Block]

The following table presents the computation of weighted-average shares used in the calculation of basic and diluted earnings per share:

	Year Ended December 31,
	2018	2017	2016
	(In thousands)
Weighted-average shares of common stock outstanding	113,452	100,325	107,001
Weighted-average potential shares of common stock outstanding:
Conversion spread related to Subordinated Convertible Debentures	8,589	23,247	21,074
Unvested RSUs, and ESPP	620	608	758
Shares used to compute diluted earnings per share	122,661	124,180	128,833