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Fair Value Measurements (Other Assumptions) (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Deposits
Carrying amount of time deposits	$ 1,973,468,000	$ 2,056,506,000
Significant Unobservable Inputs (Level 3)
Loans
Carrying amount of fixed rate performing loans	1,515,437,000	1,505,531,000
Estimated fair value of fixed rate performing loans	1,469,231,000	1,454,434,000
Deposits
Carrying amount of time deposits	1,973,468,000	2,056,506,000
Estimated fair value of time deposits	1,976,156,000	2,058,621,000
Securities Sold Under Repurchase Agreements
Carrying amount of long-term repurchase agreements		100,000,000
Estimated fair value of long-term repurchase agreements		99,504,000
Significant Other Observable Inputs (Level 2)
Other borrowed funds
Carrying amount of the long-term FHLB borrowings	436,690,000	250,000,000
Estimated fair value of long-term FHLB borrowings	$ 436,238,000	$ 249,728,000

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

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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.

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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

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- 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.

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No definition available.

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

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Amount of loan with fixed rate of interest.

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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.

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Amount of time deposit liabilities, including certificates of deposit.

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