Commitments and Contingencies Legal Proceedings (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2008	May 01, 2010
Commitments and Contingencies Disclosure [Abstract]
Estimated Unjust Gain to the Bank on Lehman Swaps Automatically Terminated and Related to Lehmans 2008 Bankruptcy	$ 43
Loss Contingency, Damages Sought Through Derivative Alternative Dispute Resolution Notice From Lehman Bankruptcy Estate, Value		$ 65.8
Percent Over LIBOR That Settlement Demand Sought by Lehman Bankruptcy Estate is Accruing Interest		14.50%

Loss contingency, damages sought through derivative alternative dispute resolution notice from Lehman bankruptcy estate, value.

No definition available.

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