Consolidated Balance Sheets Balance Sheet Parenthetical (USD $) In Thousands, except Share data, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Allowance for Doubtful Accounts Receivable, Current	$ 3,028	$ 3,516
Common Stock, Par or Stated Value Per Share	$ 0.02	$ 0.02
Common Stock, Shares Authorized	200,000,000	200,000,000
Common Stock, Shares, Issued	47,899,584	47,899,584
Common Stock, Shares, Outstanding	45,709,251	46,349,411
Treasury Stock, Shares	2,190,333	1,550,173
Preferred Stock, Par or Stated Value Per Share	$ 0.02	$ 0.02
Preferred Stock, Shares Authorized	6,000,000	6,000,000
Preferred Stock, Shares Issued	0	0
Preferred Stock, Shares Outstanding	0	0