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Debt (Summary Of Additional Information Of Credit facilities) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Revolving Secured Line Of Credit [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | $ 265.4 | $ 276.7
Average outstanding balance | 40.6 | 80.3
Warehouse Facility II [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 201.0 | 275.0
Average outstanding balance | 3.3 | 4.0
Warehouse Facility IV [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 99.0 | 12.0
Average outstanding balance | 0.5 | 5.9
Warehouse Facility V [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 99.0 | 100.0
Average outstanding balance | 1.1 | 7.8
Warehouse Facility VI [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 75.0 | 75.0
Average outstanding balance | 0.4 | 7.8
Warehouse Facility VII [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 150.0 | 0.0
Average outstanding balance | $ 7.8 | $ 0.0

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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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- Definition Average amount borrowed under the credit facility during the period. + References No definition available. + Details
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- Details
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- Details
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