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REVENUE - Summary of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	$ 73,064	$ 67,285	$ 202,820	$ 200,538
Commodity Contract Asset, Current	147		147		$ 28
Deferred revenue	3,323		3,323		1,751
Deferred revenue	3,405		3,405		2,084
Bridg Acquisition
Disaggregation of Revenue [Line Items]
Contract with Customer, Asset, after Allowance for Credit Loss, Current	147		147		28
Deferred implementation costs, net	0		0		0
Deferred revenue	3,324		3,324		1,750
Contract with Customer, Liability, Noncurrent	81		81		$ 334
Cost per Served Sale
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	49,957	43,436	138,664	128,568
Cost per Redemption
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	20,842	21,602	58,305	65,333
Other
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	2,265	2,247	5,851	6,637
Subscription revenue
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	5,941	5,421	17,217	15,471
Other revenue
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	30
Bridg platform revenue
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	$ 5,941	$ 5,421	$ 17,217	$ 15,501