Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Loss Contingencies [Line Items]
Trade settlement liability	$ 18,924	$ 16,700
ESPP employee contributions	1,551	0
Accrued transaction expense	12,639	6,399
Accrued marketing expense	10,788	4,883
Accrued salaries and benefits	2,923	1,960
Other accrued expenses	16,724	6,550
Total	66,683	39,742
Transaction losses
Loss Contingencies [Line Items]
Reserve for transaction losses	$ 3,134	$ 3,250	$ 798	$ 497

Accrued Transaction Expense

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- Definition

Trade Settlement Liability

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for the marketing, trade and selling of the entity's goods and services. Marketing costs would include expenditures for planning and executing the conception, pricing, promotion, and distribution of ideas, goods, and services; costs of public relations and corporate promotions; and obligations incurred and payable for sales discounts, rebates, price protection programs, etc. offered to customers and under government programs. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable within one year (or the operating cycle, if longer).

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount of loss contingency liability expected to be resolved within one year or the normal operating cycle, if longer.

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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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