Related Party Transactions (Related Party Payments) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Related Party Transactions [Abstract]
Operating leases	$ 27,622	$ 27,559	$ 29,240
Salaries and benefits	62,590	66,763	72,892
Billing fees	10,873	9,899	11,591
Medical advisory services	$ 2,635	$ 2,811	$ 2,993