SEGMENTS - Narrative (Details) $ in Millions	3 Months Ended
Mar. 31, 2026 USD ($) segment d	Mar. 31, 2025 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments \| segment	2
Number of reportable segments \| segment	1
Agreements with FI partners, contract termination notice period \| d	90
Minimum
Segment Reporting Information [Line Items]
Agreements with FI partners, term	3 years
Maximum
Segment Reporting Information [Line Items]
Agreements with FI partners, term	7 years
Marketers \| Revenue Benchmark \| Top Five Marketers
Segment Reporting Information [Line Items]
Concentration risk	26.00%	19.00%
Marketers \| Accounts Receivable \| Top Five Marketers
Segment Reporting Information [Line Items]
Concentration risk	26.00%	17.00%
Supplier Concentration Risk \| Financial Institution Partner \| Three Largest FI Partners
Segment Reporting Information [Line Items]
Concentration risk	88.00%	80.00%
Supplier Concentration Risk \| Financial Institution Partner \| Largest FI Partner One
Segment Reporting Information [Line Items]
Concentration risk	70.00%
United States
Segment Reporting Information [Line Items]
Capital expenditures \| $	$ 0.1
United Kingdom
Segment Reporting Information [Line Items]
Capital expenditures \| $	$ 0.1	$ 0.1

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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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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Amount of expenditure for addition to long-lived assets included in determination of segment assets by chief operating decision maker (CODM) or otherwise regularly provided to CODM. Excludes expenditure for addition to financial instrument, long-term customer relationship of financial institution, mortgage and other servicing rights, deferred policy acquisition cost, and deferred tax assets.

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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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