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Debt (Schedule of Additional Information Related to Debt Instruments) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Revolving Secured Line of Credit [Member]
Debt Instrument [Line Items]
Maximum outstanding balance	$ 199.3	$ 300.1	$ 199.3	$ 342.0
Average outstanding balance	58.9	125.6	20.8	168.0
Warehouse Facility II [Member]
Debt Instrument [Line Items]
Maximum outstanding balance	0.0	201.0	251.0	251.0
Average outstanding balance	0.0	102.8	1.8	124.2
Warehouse Facility IV [Member]
Debt Instrument [Line Items]
Maximum outstanding balance	0.0	0.0	0.0	0.0
Average outstanding balance	0.0	0.0	0.0	0.0
Warehouse Facility V [Member]
Debt Instrument [Line Items]
Maximum outstanding balance	0.0	0.0	0.0	100.0
Average outstanding balance	0.0	0.0	0.0	7.7
Warehouse Facility VI [Member]
Debt Instrument [Line Items]
Maximum outstanding balance	0.0	75.0	0.0	75.0
Average outstanding balance	0.0	61.1	0.0	48.8
Warehouse Facility VIII [Member]
Debt Instrument [Line Items]
Maximum outstanding balance	0.0	0.0	0.0	100.0
Average outstanding balance	$ 0.0	$ 0.0	$ 0.0	$ 25.9

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Average amount borrowed under the credit facility during the period.

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