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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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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SEGMENTS - Narrative (Details) $ in Thousands	3 Months Ended		6 Months Ended
SEGMENTS - Narrative (Details) $ in Thousands	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021 USD ($) segment	Jun. 30, 2020 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments \| segment			3
Capital expenditures			$ 1,790	$ 1,225
Marketers \| Revenue Benchmark \| Top Five Marketers
Segment Reporting Information [Line Items]
Concentration risk		33.00%	34.00%	38.00%
Marketers \| Revenue Benchmark \| Largest Marketers
Segment Reporting Information [Line Items]
Concentration risk	10.00%
Marketers \| Accounts Receivable \| Largest Marketers
Segment Reporting Information [Line Items]
Concentration risk			10.00%	10.00%
Supplier Concentration Risk \| Financial Institution Partner \| Largest FI Partner
Segment Reporting Information [Line Items]
Concentration risk				75.00%
Supplier Concentration Risk \| Financial Institution Partner \| Bank Of America, National Association
Segment Reporting Information [Line Items]
Concentration risk				30.00%
Supplier Concentration Risk \| Financial Institution Partner \| JP Morgan Chase Bank, National Association
Segment Reporting Information [Line Items]
Concentration risk				30.00%
United Kingdom
Segment Reporting Information [Line Items]
Capital expenditures			$ 600	$ 400