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Fair Value (Other Assumptions) (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Deposits
Carrying amount of time deposits	$ 2,012,300,000	$ 1,973,468,000
Significant Unobservable Inputs (Level 3)
Loans
Carrying amount of fixed rate performing loans	1,503,811,000	1,515,437,000
Estimated fair value of fixed rate performing loans	1,481,239,000	1,469,231,000
Deposits
Carrying amount of time deposits	2,012,300,000	1,973,468,000
Estimated fair value of time deposits	2,011,950,000	1,976,156,000
Significant Other Observable Inputs (Level 2)
Other borrowed funds
Carrying amount of the long-term FHLB borrowings	436,511,000	436,690,000
Estimated fair value of long-term FHLB borrowings	$ 465,017,000	$ 436,238,000

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.

+ 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

No definition available.

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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://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)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 2
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-Topic 942
-SubTopic 470
-Section 45
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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Amount of loan with fixed rate of interest.

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-Topic 310
-SubTopic 10
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Amount of time deposit liabilities, including certificates of deposit.

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-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
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