Accounts Payable, Accrued, and Other Liabilities (Detail) - Accounts Payable and Accrued Liabilities - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Payables and Accruals [Abstract]
Accounts payable	$ 41,009	$ 31,570
Payroll and employee benefits payable	87,821	85,575
Severance and retention bonus payable	22,425	38,557
Bonus payable	105,549	90,989
Commissions payable	68,273	66,054
Taxes payable	20,378	13,714
Other accrued liabilities	95,316	61,232
Total accounts payable and accrued liabilities	$ 440,771	$ 387,691