CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Sep. 30, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 70,107,000	$ 66,500,000
Temporary Equity, Par or Stated Value Per Share (in dollars per share)	$ 0.0001	$ 0
Temporary Equity, Liquidation Preference	$ 66,661,629	$ 0
Temporary Equity, Shares Authorized (in shares)	825,000	0
Series A preferred stock, shares issued (in shares)	635,832	0
Series A preferred stock, shares outstanding	635,832	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)	71,404,664	71,274,064
Common Stock, Shares, Outstanding (in shares)	68,747,613	68,636,965
Treasury Stock, Shares (in shares)	2,654,051	2,637,099