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REVENUE - Summary of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2024	Sep. 30, 2023	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	$ 64,002	$ 70,726		$ 126,235	$ 129,756
Commodity Contract Asset, Current	91			91		$ 41
Deferred revenue	1,679			1,679		2,405
Deferred revenue	1,707			1,707		2,271
Bridg Acquisition
Disaggregation of Revenue [Line Items]
Contract with Customer, Asset, after Allowance for Credit Loss, Current	91			91		41
Deferred revenue	1,678			1,678		2,204
Contract with Customer, Liability, Noncurrent	29			29		$ 67
Cost per Served Sale
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	40,506	49,435		80,537	88,705
Cost per Redemption
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	21,447	19,528		42,954	37,463
Other Revenue(1)
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	2,049	$ 1,763		2,744	3,588
Bridg Platform Revenue
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	$ 5,634		$ 5,975	$ 11,009	$ 11,276