CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ (72,332)	$ (66,500)
Temporary Equity, Par or Stated Value Per Share (in dollars per share)	$ 0.0001
Temporary Equity, Liquidation Preference	$ 64,758
Temporary Equity, Shares Authorized (in shares)	825,000	0
Shares issued (in shares)	625,000
Temporary Equity, Shares Outstanding (in shares)	625,000	0
Preferred Stock, Par or Stated Value Per Share (in usd per share)	$ 0.0001	$ 0.0001
Preferred Stock, Shares Authorized (in shares)	4,175,000	5,000,000
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 dollars per share)	$ 0.0001	$ 0.0001
Common Stock, Shares Authorized (in shares)	125,000,000	125,000,000
Common Stock, Shares, Issued (in shares)	71,376,164	71,274,064
Common Stock, Shares, Outstanding (in shares)	68,730,871	68,636,965
Treasury Stock, Shares (in shares)	2,645,293	2,637,099