Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Payables and Accruals [Abstract]
Payroll and benefits	$ 102,640	$ 143,383
Short-term operating lease liabilities	50,348	49,748
Deferred revenue and customer advances	34,896	30,269
Income taxes payable	39,531	26,602
Accrued severance plan obligations	10,836	10,837
Short-term finance lease liabilities	11,153	12,634
Accrued interest	1,988	10,767
Other accrued expenses	53,164	64,967
Total accrued expenses	$ 304,556	$ 349,207