Settlement Assets and Obligations - Narrative (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables from agents, business solutions customers, and others, net		$ 1,732.9	$ 1,520.2
Variable rate demand notes, maximum maturity year		2052
Due after 10 years		$ 357.0
Other Assets
Accounts, Notes, Loans and Financing Receivable [Line Items]
Advances to agents		188.5	154.9
Receivables from agents and others
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables from agents, business solutions customers, and others, net		1,732.9	1,508.5
Provision for doubtful accounts	[1]	19.4	14.1	$ 8.9
Receivables from Business Solutions customers
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables from agents, business solutions customers, and others, net			11.7
Provision for doubtful accounts	[1]	1.4	$ 3.8	$ 4.2
State and municipal variable-rate demand notes
Accounts, Notes, Loans and Financing Receivable [Line Items]
Due after 10 years		$ 86.8

[1] Provision does not include losses from chargebacks or fraud associated with transactions initiated through the Company’s digital channels, as these losses are not credit-related. The Company recognized losses that were not credit-related of $42.2 million, $37.5 million, and $51.4 million for the years ended December 31, 2023, 2022, and 2021, respectively.