Regulatory Requirements and Other Restrictions (Narrative) (Details) $ in Millions	Dec. 31, 2016 USD ($)
Branch Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
FRB, net reserve requirement	$ 124

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Balance Type:	na
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