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Debt (Summary Of Additional Information Of Credit facilities) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014
Revolving Secured Line Of Credit [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | $ 206.3 | $ 204.7
Average outstanding balance | 39.1 | 103.6
Warehouse Facility II [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 200.8 | 290.2
Average outstanding balance | 7.9 | 70.3
Warehouse Facility IV [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 35.0 | 26.7
Average outstanding balance | 9.2 | 22.0
Warehouse Facility V [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 99.2 | 75.0
Average outstanding balance | 12.2 | 9.2
Warehouse Facility VI [Member] |  |
Debt Instrument [Line Items] |  |
Maximum outstanding balance | 15.0 | 0.0
Average outstanding balance | $ 1.5 | $ 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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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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- Definition Maximum amount borrowed under the credit facility at any time during the period. + References No definition available. + Details
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- Details
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Balance Type: |
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- Details
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Balance Type: |
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- Details
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- Details
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- Details
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