Calculation Of Net Income Per Share (Weighted-Average Shares Used In Calculation Of Basic And Diluted EPS) (Details) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share [Abstract]
Weighted-average number of common shares outstanding	117,139	133,417
Conversion spread related to Convertible Debentures	15,812	14,286
Unvested restricted stock units	869	817
Stock options	8	37
Employee stock purchase plan	22	43
Shares used to compute diluted net income per share	133,850	148,600