Settlement Assets and Obligation - Summary of Investment Securities in Unrealized Position (Details) $ in Millions	Dec. 31, 2023 USD ($) Securities
State and municipal debt securities
Summary of Investment Holdings [Line Items]
Number of securities less than one year \| Securities	27
Fair value less than one year	$ 84.6
Unrealized losses less than one year	$ (0.4)
Number of securities one year or greater \| Securities	267
Fair value one year or greater	$ 572.2
Unrealized losses one year or greater	$ (46.2)
Corporate debt securities
Summary of Investment Holdings [Line Items]
Number of securities one year or greater \| Securities	14
Fair value one year or greater	$ 52.2
Unrealized losses one year or greater	$ (4.5)
United States government agency mortgage-backed securities
Summary of Investment Holdings [Line Items]
Number of securities one year or greater \| Securities	10
Fair value one year or greater	$ 11.5
Unrealized losses one year or greater	$ (0.5)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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