Summary of Significant Accounting Policies (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) segment	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Accounting Policies and Supplemental Information [Line Items]
Number of operating segments | segment	1
Allowance for doubtful accounts receivable	$ (300)	$ (300)
Impairment of equity method investments options		11,600
Carrying value		7,800
Sale of equity method investment	0	25,732	$ 0
Gain on disposal	$ 0	17,889	0
Revenue from contract with customer, standard contract automatic renewal, term	1 year
Advertising costs	$ 1,500	2,200	1,700
Company matching contribution, percent	50.00%
Employer matching contribution, percent of employees' gross pay	6.00%
Requisite service period (in years)	1 year
Compensation and Benefits and Technology Expenses
Accounting Policies and Supplemental Information [Line Items]
Research and development costs	$ 148,000	$ 108,300	$ 84,100
Minimum
Accounting Policies and Supplemental Information [Line Items]
Revenue from contract with customer, standard contract term	3 years
Revenue from contract with customer, card network, term	3 years
Revenue from contract with customer, card network renewal, term	1 year
Minimum | Computer Equipment, and Furniture and Fixtures
Accounting Policies and Supplemental Information [Line Items]
Property, plant and equipment, useful life	3 years
Maximum
Accounting Policies and Supplemental Information [Line Items]
Revenue from contract with customer, standard contract term	5 years
Revenue from contract with customer, card network, term	5 years
Revenue from contract with customer, card network renewal, term	2 years
Maximum | Computer Equipment, and Furniture and Fixtures
Accounting Policies and Supplemental Information [Line Items]
Property, plant and equipment, useful life	5 years