Net Revenues and Accounts Receivable (Details 1) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Accounts receivable attributable to major payer sources of reimbursement
Gross Accounts Receivable	$ 251,464	$ 259,857
Less: Allowance for doubtful accounts	(9,006)	(8,777)
Net Accounts Receivable	242,458	251,080
Medicare [Member]
Accounts receivable attributable to major payer sources of reimbursement
Gross Accounts Receivable	188,556	192,541
Medicaid and Local Government [Member]
Accounts receivable attributable to major payer sources of reimbursement
Gross Accounts Receivable	29,946	31,259
Commercial Insurance and Other [Member]
Accounts receivable attributable to major payer sources of reimbursement
Gross Accounts Receivable	$ 32,962	$ 36,057