SEGMENT AND GEOGRAPHICAL INFORMATION - Reconciliation of Total Segment Profit to Income before applicable Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Gross profit	$ 4,419,823	$ 2,733,409	$ 1,889,685
Less: Product development	1,399,079	885,681	674,165
Less: Sales and marketing	1,617,189	1,109,670	625,126
Less: General and administrative	983,326	579,203	436,878
Less: Transaction and loan losses	187,991	177,670	126,959
Less: Bitcoin impairment losses	71,126	0	0
Less: Gain on sale of asset group	0	0	(373,445)
Less: Interest expense, net	33,124	56,943	21,516
Other expense (income), net	(29,474)	(291,725)	273
Income before income tax	157,462	215,967	378,213
Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Gross profit	4,419,823	2,733,409	1,848,095
Segment Reconciling Items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Gross profit	$ 0	$ 0	$ 41,590