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v3.21.1

Debt (Schedule of Additional Information Related to Debt Instruments) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2021 | Mar. 31, 2020
Revolving Secured Line of Credit [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | $ 216.0 | $ 268.2
Average outstanding balance | 68.9 | 85.2
Warehouse Facility II [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 201.0 | 201.0
Average outstanding balance | 42.8 | 20.4
Warehouse Facility IV [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 0.0 | 0.0
Average outstanding balance | 0.0 | 0.0
Warehouse Facility V [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 0.0 | 50.0
Average outstanding balance | 0.0 | 8.2
Warehouse Facility VI [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 0.0 | 0.0
Average outstanding balance | 0.0 | 0.0
Warehouse Facility VII [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 0.0 | 100.0
Average outstanding balance | 0.0 | 21.7
Warehouse Facility VIII [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 0.0 | 49.0
Average outstanding balance | $ 0.0 | $ 7.6

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- 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. + References No definition available. + Details
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