State-Sponsored Health Plans Rate Settlement Agreement (Details) (USD $)		9 Months Ended
Dec. 31, 2012	Sep. 30, 2013 Medicaid Premium Revenue [Member]
State-Sponsored Health Plans Rate Settlement Agreement [Line Items]
State settlement premium revenue		$ 51,700,000
Settlement account balance, beginning	0
Settlement account payment, maximum		264,000,000
Settlement account payment, current balance		51,700,000
Receivable with imputed interest, discount		$ 3,700,000

Disclosure of the unamortized amount of the discount on the note or receivable which is deducted from the face amount of the receivable or loan. The discount or premium is the difference between the present value and the face amount.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

Name:	us-gaap_ReceivableWithImputedInterestDiscount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant