Condensed Consolidated Balance Sheets Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 3,216	$ 3,213
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	95,000,000	95,000,000
Common stock, shares issued	45,292,836	45,094,191
Common stock, shares outstanding	45,292,836	45,094,191
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Treasury Stock, shares	0	0