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Debt Debt (Schedule of Principal Debt Outstanding) (Details) - USD ($) $ in Millions | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | ---
Debt Instrument [Line Items] |  |  |
Debt Instrument, Face Amount |  | $ 2,086.3 | $ 1,752.5
Debt Instrument, Unamortized Discount |  | (1.7) | 0.0
Debt Instrument, Carrying Amount |  | 2,084.6 | 1,752.5
Revolving Secured Line Of Credit [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Face Amount |  | 57.7 | 119.5
Debt Instrument, Unamortized Discount |  | 0.0 | 0.0
Debt Instrument, Carrying Amount |  | 57.7 | 119.5
Secured financings [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Face Amount | [1] | 1,478.6 | 1,333.0
Debt Instrument, Unamortized Discount | [1] | 0.0 | 0.0
Debt Instrument, Carrying Amount | [1] | 1,478.6 | 1,333.0
Senior Notes [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Face Amount |  | 550.0 | 300.0
Debt Instrument, Unamortized Discount |  | (1.7) | 0.0
Debt Instrument, Carrying Amount |  | $ 548.3 | $ 300.0
[1] | Warehouse facilities and Term ABS financings

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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399 + Details
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- Definition Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13433-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13476-108611 + Details
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- Definition The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400 + Details
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