Basic and Diluted Net Income (Loss) Per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Net (loss) income (numerator)
Net (loss) income from continuing operations	$ (12,287)	$ 3,868
Net loss from discontinued operations	(866)	(2,049)
Net (loss) income	$ (13,153)	$ 1,819
Shares (denominator)
Weighted-average basic common shares outstanding (in shares)	84,607	92,484
Effect of dilutive securities-stock rights (in shares)	0	1,740
Weighted-average diluted common shares outstanding (in shares)	84,607	94,224
Basic and diluted per share amounts
Basic net (loss) income per share from continuing operations	$ (0.15)	$ 0.04
Basic net loss per share from discontinued operations	$ (0.01)	$ (0.02)
Total basic net (loss) income per share	$ (0.16)	$ 0.02
Diluted net (loss) income per share from continuing operations	$ (0.15)	$ 0.04
Diluted net loss per share from discontinued operations	$ (0.01)	$ (0.02)
Diluted net (loss) income per share	$ (0.16)	$ 0.02
Anti-dilutive weighted-average stock rights outstanding (in shares)	0