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Segment Reporting - Reconciliation of Reportable Segment ROA Pre-Tax Profit to Condensed Consolidated Income before Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Segment Reporting Information [Line Items]
Income before income taxes	$ 393.1	$ 389.8
U.S. reportable segment
Segment Reporting Information [Line Items]
U.S. ROA pre-tax profit	340.5	338.2
Other operating segment
Segment Reporting Information [Line Items]
Other operating segment pre-tax profit	$ 52.6	$ 51.6

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Segment Reporting, Other Operating Segments Item, ROA Pre-Tax Profit

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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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