Other Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Accrued Liabilities, Current [Abstract]
Accrued professional liabilities	$ 14,541	$ 14,362
Contingent purchase price payable	1,000	5,509
Current income taxes payable	0	7,892
Refunds payable	29,626	48,415
Other	47,404	43,059
Total other accrued liabilities	$ 92,571	$ 119,237