Accrued Liabilities - Detail of Accrued Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Payables and Accruals [Abstract]
Accrued incentives	$ 96,708	$ 69,583
Accrued payroll taxes and other employee-related expenses	75,881	56,394
Accrued commissions	65,794	59,357
Other accrued expenses	44,987	31,900
Accrued sales tax and value-added taxes	23,681	11,249
Accrued vacation	9,741	31,706
Total	316,792	$ 260,189
Cash payments for pay-out of accrued vacation	$ 34,500