Amazon - Summary of Customer Incentive Asset within Deferred Costs and Other Assets (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Warrants And Rights Note Disclosure [Abstract]
Balance at December 31, 2019			$ 152,534
Initial value for estimate of vested or expected to vest warrants			5,186
Amortization of customer incentive asset	$ (9,500)	$ (6,900)	(18,556)	$ (13,200)
Balance at June 30, 2020	$ 139,164		$ 139,164