Settlement Assets and Customer/Subscriber Account Balances and Related Obligations - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Settlement and customer/subscriber account obligations	$ 753,850		$ 755,754
SMB Payments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Merchant reserves held by sponsor banks	109,200		98,000
Provision for merchant losses	4,700	$ 1,000
B2B Payments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for merchant losses	200	$ 0
Enterprise Payments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Deposits, agency-owned accounts	46,200		19,600
Due To ACH Payees \| B2B Payments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Settlement and customer/subscriber account obligations	1,600		1,200
Due To ACH Payees \| Bank \| B2B Payments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Settlement and customer/subscriber account obligations	$ 79,100		$ 69,000