Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share Reconciliation [Abstract]
Earnings from continuing operations	$ 6,347	$ 9,595	$ 25,812	$ 25,415
Weighted-average shares outstanding for basic earnings per share (in shares)	64,239,000	64,286,000	64,411,000	64,240,000
Common equivalent shares:
Effect of stock-based compensation awards (in shares)	932,000	985,000	930,000	967,000
Weighted-average shares outstanding assuming dilution (in shares)	65,171,000	65,271,000	65,341,000	65,207,000
Basic earnings per share from continuing operations (in dollars per share)	$ 0.10	$ 0.15	$ 0.40	$ 0.40
Diluted earnings per share from continuing operations (in dollars per share)	$ 0.10	$ 0.15	$ 0.40	$ 0.39
Anti-dilutive securities excluded from computation of earnings per share (in shares)			0	0