Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Assets:
Settlement assets	$ 3,486.8	$ 2,843.5
Derivatives	126.1	247.7
Liabilities:
Derivatives	98.9	183.8
Recurring
Assets:
Derivatives	126.1	247.7
Total assets	1,471.5	1,654.5
Liabilities:
Derivatives	98.9	183.8
Total liabilities	98.9	183.8
Recurring \| Money market funds
Assets:
Settlement assets	11.7	7.9
Recurring \| State and municipal debt securities
Assets:
Settlement assets	933.3	1,219.9
Recurring \| Asset-backed securities
Assets:
Settlement assets	184.1
Recurring \| Corporate and other debt securities
Assets:
Settlement assets	146.9	57.8
Recurring \| State and municipal variable rate demand notes
Assets:
Settlement assets	48.9	84.8
Recurring \| United States government agency mortgage-backed securities
Assets:
Settlement assets	20.5	36.4
Recurring \| Level 1
Assets:
Total assets	11.7	7.9
Recurring \| Level 1 \| Money market funds
Assets:
Settlement assets	11.7	7.9
Recurring \| Level 2
Assets:
Derivatives	126.1	247.7
Total assets	1,459.8	1,646.6
Liabilities:
Derivatives	98.9	183.8
Total liabilities	98.9	183.8
Recurring \| Level 2 \| State and municipal debt securities
Assets:
Settlement assets	933.3	1,219.9
Recurring \| Level 2 \| Asset-backed securities
Assets:
Settlement assets	184.1
Recurring \| Level 2 \| Corporate and other debt securities
Assets:
Settlement assets	146.9	57.8
Recurring \| Level 2 \| State and municipal variable rate demand notes
Assets:
Settlement assets	48.9	84.8
Recurring \| Level 2 \| United States government agency mortgage-backed securities
Assets:
Settlement assets	$ 20.5	$ 36.4

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Cash received or short term receivables for unsettled money transfers, money orders, consumer payments, or business to business payments. Settlement assets include clearing and settling customers payments due to and from financial institutions and may include cash and cash equivalents.

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