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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
	Mar. 31, 2026	Mar. 31, 2025
Segment Reporting Information [Line Items]
Income before income taxes	$ 448.3	$ 393.1
U.S. reportable segment
Segment Reporting Information [Line Items]
U.S. ROA pre-tax profit	383.9	340.5
Other operating segment
Segment Reporting Information [Line Items]
Other operating segment pre-tax profit	$ 64.4	$ 52.6

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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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