Prepaid Expenses and Other Current Assets, Accrued Expenses, Other Current Liabilities, and Other Liabilities - Components of Other Current Liabilities and Other Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Other current liabilities:
Short term lease liability	$ 91,104
Sales tax payable	62,173		$ 49,989
Sales return reserve	38,042		35,707
Other current liabilities	45,544		42,299
Total current other liabilities	236,863	$ 118,371	127,995
Other liabilities:
Construction costs under build-to-suit leases	0		60,089
Deferred rent	0		99,746
Other liabilities	6,940		553
Total other liabilities	$ 6,940	$ 4,392	$ 160,388