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Hedging Activities (Narrative) (Details) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2015 USD ($) | Sep. 30, 2014 USD ($) | Sep. 30, 2015 USD ($) financial_institution | Sep. 30, 2014 USD ($) | Dec. 31, 2014 financial_institution
General Discussion of Derivative Instruments and Hedging Activities [Abstract] |  |  |  |  |
Number of financial institutions | financial_institution |  |  | 5 |  | 5
Gain (loss) on fair value hedges recognized in earnings | $ 62.2 | $ 29.5 | $ 58.9 | $ 23.0 |

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- Definition Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959 + Details
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