Commitments and Contingencies (Tax advantaged payments) (Details) $ in Millions	9 Months Ended
Sep. 30, 2015 USD ($)
Investments In Affordable Housing Projects [Abstract]
2015	$ 13.9
2016	31.3
2017	12.6
2018	0.5
2019	0.5
Thereafter	$ 5.4

Commitments to fund Qualified Affordable Housing Project Investments Funding Remainder of Year

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Commitments to fund Qualified Affordable Housing Project Investments Funding Year Five and Thereafter

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Commitments to fund Qualified Affordable Housing Project Investments Funding Year Four

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Commitments to fund Qualified Affordable Housing Project Investments Funding Year One

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Commitments to fund Qualified Affordable Housing Project Investments Funding Year Three

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Commitments to fund Qualified Affordable Housing Project Investments Funding Year Two

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