Unaudited Condensed Consolidated Balance Sheets Parenthetical (USD $) In Thousands, except Share data, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Statement of Financial Position [Abstract]
Allowance for Doubtful Accounts Receivable, Current	$ 4,339	$ 5,215
Preferred Stock, Par or Stated Value Per Share (in usd per share)	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized (in shares)	2,000,000	2,000,000
Preferred Stock, Shares Issued (in shares)	0	0
Preferred Stock, Shares Outstanding (in shares)	0	0
Common Stock, Par or Stated Value Per Share (in usd per share)	$ 0.01	$ 0.01
Common Stock, Shares Authorized (in shares)	90,000,000	90,000,000
Common Stock, Shares, Issued (in shares)	32,813,555	32,108,212
Treasury Stock, Shares (in shares)	825,956	216,695