Commitmens and Contingencies (Tax advantaged payment) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015
Investments In Affordable Housing Projects [Abstract]
2015	$ 36.9
2016	17.4
2017	6.6
2018	0.4
2019	0.3
Thereafter	$ 5.0

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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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