Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Accounts receivable, allowances (in dollars)	$ 2,989	$ 2,842
Property and equipment, accumulated depreciation (in dollars)	$ 42,185	$ 46,871
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	79,100,000	78,728,000
Treasury stock, shares	44,000	32,000