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Debt (Schedule Of Outstanding Term ABS Financings) (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2017 USD ($)
Term ABS 2015-1 [Member] |
Debt Instrument [Line Items] |
Debt financing close date | Jan. 29, 2015
Net Book Value Of Loans Pledged As Collateral | $ 375.9
Term ABS 2015-2 [Member] |
Debt Instrument [Line Items] |
Debt financing close date | Aug. 20, 2015
Net Book Value Of Loans Pledged As Collateral | $ 375.5
Term ABS 2016-1 [Member] |
Debt Instrument [Line Items] |
Debt financing close date | Feb. 26, 2016
Net Book Value Of Loans Pledged As Collateral | $ 481.4
Term ABS 2016-2 [Member] |
Debt Instrument [Line Items] |
Debt financing close date | May 12, 2016
Net Book Value Of Loans Pledged As Collateral | $ 437.8
Term ABS 2016-3 [Member] |
Debt Instrument [Line Items] |
Debt financing close date | Oct. 27, 2016
Net Book Value Of Loans Pledged As Collateral | $ 437.8
Term ABS 2017-1 [Member] |
Debt Instrument [Line Items] |
Debt financing close date | Feb. 23, 2017
Net Book Value Of Loans Pledged As Collateral | $ 437.8
Term ABS 2017-2 [Member] |
Debt Instrument [Line Items] |
Debt financing close date | Jun. 29, 2017
Net Book Value Of Loans Pledged As Collateral | $ 563.2
Term ABS 2017-3 [Member] |
Debt Instrument [Line Items] |
Debt financing close date | Oct. 26, 2017
Net Book Value Of Loans Pledged As Collateral | $ 437.6

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