BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2026 USD ($) segment	Dec. 31, 2025 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of operating segments \| segment	1
Number of reportable segments \| segment	1
Marketable securities \| $	$ 527,380	$ 587,828
Accounts Receivable \| Customer Concentration Risk \| Combined Bank Partners
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	46.00%	46.00%
Accounts Receivable \| Customer Concentration Risk \| Bank Partner A
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	27.00%	26.00%
Accounts Receivable \| Customer Concentration Risk \| Bank Partner B
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	19.00%	20.00%
Accounts Receivable \| Customer Concentration Risk \| Card Network Partner
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	49.00%	50.00%
U.S. government securities
Summary Of Significant Accounting Policies [Line Items]
Marketable securities \| $	$ 508,267	$ 563,594
U.S. government securities \| Debt Securities \| Security Concentration Risk
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	96.00%	96.00%

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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