Summary of Significant Accounting Policies - Additional Information (Details)	12 Months Ended
	Dec. 31, 2021 USD ($) Segment Lease	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of reportable segment | Segment	1
Advertising expense	$ 1,000,000,000.0	$ 1,600,000,000	$ 1,400,000,000
Percentage of concentrations of risk, cash and cash equivalents	15.00%	7.00%
Number of finance leases outstanding | Lease	0
Percentage of merchants payable amount denominated in RMB	76.00%	85.00%
Net losses resulting from foreign exchange transactions	$ 15,000,000	$ 26,000,000	$ 9,000,000
Cumulative translation gain (loss)	2,000,000	(1,000,000)
Core Marketplace
Summary Of Significant Accounting Policies [Line Items]
Net gains or losses recognized in core marketplace revenue	$ 0	$ 0
Foreign Exchange Forward Contracts
Summary Of Significant Accounting Policies [Line Items]
Derivative contract term	12 months
Restricted Stock Units (RSUs)
Summary Of Significant Accounting Policies [Line Items]
Award requisite service period	4 years
Minimum
Summary Of Significant Accounting Policies [Line Items]
Original maturities of marketable securities	90 days
Minimum | Restricted Stock Units (RSUs)
Summary Of Significant Accounting Policies [Line Items]
Award service condition satisfaction period	4 years
Maximum | Restricted Stock Units (RSUs)
Summary Of Significant Accounting Policies [Line Items]
Award service condition satisfaction period	5 years
United States
Summary Of Significant Accounting Policies [Line Items]
Percentage of cash and cash equivalents	83.00%	92.00%