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Fair Value Measurements (Details 4) (USD $)	Sep. 30, 2014	Dec. 31, 2013
Deposits
Carrying amount of time deposits	$ 2,522,239,000	$ 2,651,303,000
Fair Value, Inputs, Level 3 [Member]
Assets and liabilities reported at fair value on recurring
Estimated fair value of fixed rate performing loans	1,238,356,000	1,196,916,000
Loans
Carrying amount of fixed rate performing loans	1,307,205,000	1,243,252,000
Deposits
Carrying amount of time deposits	2,522,239,000	2,651,303,000
Estimated fair value of time deposits	2,521,059,000	2,649,452,000
Securities Sold Under Repurchase Agreements
Carrying amount of long-term repurchase agreements	610,000,000	710,000,000
Estimated fair value of long-term repurchase agreements	663,833,000	792,215,500
Fair Value, Inputs, Level 2 [Member]
Other borrowed funds
Carrying amount of the long-term FHLB borrowings	6,281,000	8,950,000
Estimated fair value of long-term FHLB borrowings	$ 6,665,000	$ 8,950,000

X

- Definition

Represents the aggregate of long-term FHLB borrowings reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with fair value disclosures required in footnote disclosures to financial statements. Such borrowings are initially due beyond one year or beyond the normal operating cycle, if longer.

+ References

No definition available.

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X

- Definition

Represents the portion of fixed rate performing loans valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Fixed rate loan represents loans charging borrowers fixed rates of interest.

+ References

No definition available.

+ Details

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X

- Definition

The carrying value as of the balance sheet date of securities that an institution sells and agrees to repurchase under a long term agreement (the identical or substantially the same securities) as a seller-borrower at a specified date for a specified price, also known as a repurchase agreement.

+ References

No definition available.

+ Details

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X

- Definition

Represents the portion of time deposits valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Time deposits include certificates of deposits, individual retirement accounts and open accounts.

+ References

No definition available.

+ Details

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- Details

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 45

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- Definition

Amount of loan with fixed rate of interest.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

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-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Amount of deposits that cannot be withdrawn before a set date without penalty or for which notice of withdrawal is required. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.12)

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