Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Payroll and benefits	$ 116,526	$ 117,636
Deferred revenue and customer advances	58,873	65,653
Accrued settlement costs	35,908	35,304
Accrued interest	28,083	13,046
Income taxes payable	25,453	37,961
Accrued severance plan obligations	15,266	14,053
Other accrued expenses	58,554	55,016
Total accrued expenses	$ 338,663	$ 338,669