Earnings Per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Net Income (Loss)
Income (loss) from continuing operations	$ 4,451	$ 8,869	$ 17,707	$ 23,299
Income (loss) from discontinued operations	(12,624)	(6)	(10,903)	(117,348)
Net income (loss)	$ (8,173)	$ 8,863	$ 6,804	$ (94,049)	$ (83,353)
Basic earnings (loss) per common share
Weighted-average common shares outstanding used in earnings (loss) per share computations	62,538	62,963	62,485	62,960
Continuing operations (in dollars per share)	$ 0.07	$ 0.14	$ 0.28	$ 0.37
Discontinued operations (in dollars per share)	$ (0.20)	$ 0.00	$ (0.17)	$ (1.86)
Basic earnings (loss) per common share (in dollars per share)	$ (0.13)	$ 0.14	$ 0.11	$ (1.49)
Diluted earnings (loss) per common share
Shares used in diluted earnings (loss) per share computations	62,994	63,205	62,808	63,162
Continuing operations (in dollars per share)	$ 0.07	$ 0.14	$ 0.28	$ 0.37
Discontinued operations (in dollars per share)	$ (0.20)	$ 0.00	$ (0.17)	$ (1.86)
Diluted earnings (loss) per common share (in dollars per share)	$ (0.13)	$ 0.14	$ 0.11	$ (1.49)
Computation of Shares Used in Earnings Per Share Computations
Weighted-average common shares outstanding (in shares)	62,538	62,963	62,485	62,960
Weighted-average common equivalent shares - dilutive effect of stock options and awards	456	242	323	202
Shares used in diluted earnings per share computations	62,994	63,205	62,808	63,162