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Fair Value Measurements (Other Assumptions) (Details) - USD ($)	Jun. 30, 2021	Dec. 31, 2020
Deposits
Carrying amount of time deposits	$ 2,143,987,000	$ 2,153,541,000
Level 3
Loans
Carrying amount of fixed rate performing loans	1,664,177,000	1,812,413,000
Estimated fair value of fixed rate performing loans	1,610,401,000	1,747,257,000
Deposits
Carrying amount of time deposits	2,143,987,000	2,153,541,000
Estimated fair value of time deposits	2,141,515,000	2,148,976,000
Level 2
Other borrowed funds
Carrying amount of the long-term FHLB borrowings	436,233,000	436,372,000
Estimated fair value of long-term FHLB borrowings	$ 475,671,000	$ 480,475,000

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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+ Details

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- Definition

Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

+ References

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
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-Section 50
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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Amount of loan with fixed rate of interest.

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Amount of time deposit liabilities, including certificates of deposit.

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