SEGMENTS - Narrative (Details) $ in Millions	3 Months Ended
Mar. 31, 2024 segment	Mar. 31, 2023 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments \| segment	3
Marketers \| Revenue Benchmark \| Top Five Marketers
Segment Reporting Information [Line Items]
Concentration risk	21.00%	16.00%
Marketers \| Accounts Receivable \| Top Five Marketers
Segment Reporting Information [Line Items]
Concentration risk	16.00%	21.00%
Supplier Concentration Risk \| Financial Institution Partner \| Three Largest FI Partners
Segment Reporting Information [Line Items]
Concentration risk	90.00%	70.00%
Supplier Concentration Risk \| Financial Institution Partner \| Largest FI Partner One
Segment Reporting Information [Line Items]
Concentration risk	50.00%
Supplier Concentration Risk \| Financial Institution Partner \| Largest FI Partner Two
Segment Reporting Information [Line Items]
Concentration risk	15.00%
Supplier Concentration Risk \| Financial Institution Partner \| Largest FI Partner Three
Segment Reporting Information [Line Items]
Concentration risk	10.00%
United Kingdom
Segment Reporting Information [Line Items]
Capital expenditures \| $		$ 0.1

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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