Unaudited Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 851	$ 847
Cumulative convertible preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Cumulative convertible preferred stock, shares authorized	100,000	100,000
Cumulative convertible preferred stock, shares issued	0	0
Cumulative convertible preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized	80,000,000	80,000,000
Common stock, shares issued	55,154,224	54,633,726
Common stock, shares outstanding	53,429,599	53,357,811
Treasury stock, shares	704,350	449,397