Investment Securities (Details Textual) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Investment Securities (Textuals) [Abstract]
Federal Home Loan Bank Stock	$ 118,000,000us-gaap_FederalHomeLoanBankStock	$ 110,000,000us-gaap_FederalHomeLoanBankStock
Federal Reserve Bank Stock	71,000,000us-gaap_FederalReserveBankStock	71,000,000us-gaap_FederalReserveBankStock
Securities pledged as collateral	$ 2,800,000,000	$ 2,900,000,000

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The fair value of available-for-sale securities that serve as collateral for borrowings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5086-111524

+ Details

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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 325

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6478792&loc=d3e63345-112809

+ Details

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- Definition

Federal Reserve Bank stock represents an equity interest in the Federal Reserve Bank. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

+ Details

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