Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share Reconciliation [Abstract]
Earnings from continuing operations	$ 7,799	$ 11,556	$ 23,215	$ 29,437
Weighted-average shares outstanding for basic earnings per share (in shares)	64,052,000	63,456,000	63,972,000	63,439,000
Common equivalent shares:
Effect of stock-based compensation awards (in shares)	984,000	1,211,000	835,000	1,039,000
Weighted-average shares outstanding assuming dilution (in shares)	65,036,000	64,667,000	64,807,000	64,478,000
Basic earnings per share from continuing operations (in dollars per share)	$ 0.12	$ 0.18	$ 0.36	$ 0.46
Diluted earnings per share from continuing operations (in dollars per share)	$ 0.12	$ 0.18	$ 0.36	$ 0.46
Anti-dilutive securities excluded from computation of earnings per share (in shares)			0	77,000