CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Allowance for Doubtful Accounts Receivable	$ 7,919	$ 7,197
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	64,603,344	64,113,785
Common stock, shares outstanding	48,822,013	48,723,414
Non-vesting restricted shares	993,934	1,235,904
Treasury Stock, Shares	15,781,331	15,390,371