Borrowings (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011
Borrowings [Abstract]
Non-insured customer funds Secured by investment portfolio	$ 702.8
Total outstanding advances	104.3
FHLB issued letters of credit	169.5
Structured repurchase agreements	400.0
Other long-term debt	$ 7.5

Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Reference 7: http://www.xbrl.org/2003/role/presentationRef

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+ Details