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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, 2016 | Dec. 31, 2015
Revolving Secured Line Of Credit [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | $ 186.4 | $ 206.3
Average outstanding balance | 30.8 | 39.1
Warehouse Facility II [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 200.1 | 200.8
Average outstanding balance | 3.8 | 7.9
Warehouse Facility IV [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 12.0 | 35.0
Average outstanding balance | 12.0 | 9.2
Warehouse Facility V [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 100.0 | 99.2
Average outstanding balance | 1.6 | 12.2
Warehouse Facility VI [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 49.9 | 15.0
Average outstanding balance | $ 3.3 | $ 1.5

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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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Balance Type: | credit
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- Details
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- Details
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- Details
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- Details
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