Basis of Presentation (Details 2) (USD $)	1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 31, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 item	Sep. 30, 2012	Dec. 31, 2012
Basis of Presentation
Number of businesses under which the entity is managed and operated				1
Estimated liability for appeals		$ 27,484,000		$ 27,484,000		$ 21,787,000
Allowance for doubtful accounts
Balance at the beginning of the period				830,000	1,158,000	1,158,000
Provision				551,000		19,000
Recoveries				(42,000)
Charge-offs				(167,000)		(347,000)
Balance at the end of the period		1,172,000		1,172,000		830,000
Estimated allowance for appeals and estimated liability for appeals
Balance at the beginning of the period				28,772,000	10,383,000	10,383,000
Provision				17,261,000		20,513,000
Appeals found in Providers favor				(6,031,000)		(2,124,000)
Balance at the end of the period		40,002,000		40,002,000		28,772,000
Estimated allowance for appeals that apply to uncollected accounts receivable		12,518,000		12,518,000		6,985,000
Revenue Recognition
Number of characteristics for revenue recognition				4
Amount of maximum balance per bank account as insured by Federal Deposit Insurance Corporation		250,000		250,000
Depreciation and amortization expense related to property and equipment		8,100,000	7,000,000	23,300,000	19,800,000
Stock repurchase agreement, authorized amount	$ 50,000,000
Maximum period for repurchase for common stock	2 years