Prepaid Expenses and Other Current Assets, Accrued Expenses, Other Current Liabilities, and Other Liabilities - Components of Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Accrued expenses:
Employee compensation and related benefits	$ 91,914	$ 55,142
Advertising	67,259	38,888
Accrued property, plant and equipment	13,955	8,592
Credit card	16,740	4,573
Audit, legal and professional fees	1,703	1,749
Other accrued expenses	21,426	11,303
Total accrued expenses	$ 212,997	$ 120,247