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Settlement Assets and Obligations - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2025 | Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Variable rate demand notes, maximum maturity year | 2045 |
Due after 10 years | $ 422.0 |
Other Assets |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Advances to agents | 221.8 | $ 209.1
State and municipal variable-rate demand notes |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Due after 10 years | $ 1.4 |

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