Investment Securities (Investment Securities Pledged To Secure Borrowings And Public Deposits) (Details) $ in Thousands	Mar. 31, 2017 USD ($)
Investments, Debt and Equity Securities [Abstract]
To Federal Home Loan Bank to secure borrowings, amortized cost	$ 507
To Federal Home Loan Bank to secure borrowings, fair value	514
To state and local governments to secure public deposits, amortized cost	897,105
To state and local governments to secure public deposits, fair value	895,844
Other securities pledged principally to secure repurchase agreements, amortized cost	434,549
Other securities pledged principally to secure repurchase agreements, fair value	429,702
Total pledged securities, amortized cost	1,332,161
Total pledged securities, fair value	$ 1,326,060

Pledged Assets Not Separately Reported Other Securities Pledged Amortized Cost

No definition available.

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- Definition

Pledged Assets Not Separately Reported Securities Pledged For State and Local Governments

+ References

No definition available.

+ Details

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- Definition

Pledged Assets Separately Reported Other Securities Pledged At Fair Value

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No definition available.

+ Details

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- Definition

Pledged Assets Separately Reported Securities Pledged For State and Local Governments At Fair Value

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

The sum of the fair values, as of the date of each statement of financial position presented, of securities that are restricted as collateral for the payment of related debt obligations, primarily secured borrowings and repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728

+ Details

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- Definition

The fair value, as of the date of each statement of financial position presented, of securities which are owned but transferred to serve as collateral for the payment of the FHLB debt obligations, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

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+ Details

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- Definition

The carrying amount as of the date of the latest financial statement presented of securities which are owned but transferred to serve as collateral for FHLB debt obligations, and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=64858031&loc=SL6224234-111729

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- Definition

Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

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