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Segment Reporting - Reconciliation of Reportable Segment ROA Pre-Tax Profit to Consolidated Income before Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Segment Reporting Information [Line Items]
Income before income taxes	$ 436.6	$ 386.4	$ 829.8	$ 776.2
U.S. reportable segment
Segment Reporting Information [Line Items]
U.S. ROA pre-tax profit	379.3	335.1	719.7	673.3
Other operating segment
Segment Reporting Information [Line Items]
Other operating segment pre-tax profit	$ 57.3	$ 51.3	$ 110.1	$ 102.9

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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