Fair Value Disclosures, Changes in Fair Value for Financial Assets (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Changes in fair value for financial assets [Abstract]
Loans held for sale	$ (1,816)	$ (2,598)
Capitalized mortgage loan servicing rights, net gains (losses)	7,558	3,257
Impairment charges recognized [Abstract]
Collateral dependent loans, carrying amount	1,100		$ 1,400
Collateral dependent loans, valuation allowance	500		600
Additional provision for credit losses on collateral dependent loans	100	200
Other real estate, carrying amount	0		0
Other real estate, valuation allowance	30		$ 30
Other real estate, additional charge	0	0
Mortgage Loans [Member]
Changes in fair value for financial assets [Abstract]
Loans held for sale	(1,816)	(2,598)
Mortgage Loan Servicing, Net [Member]
Changes in fair value for financial assets [Abstract]
Capitalized mortgage loan servicing rights, net gains (losses)	$ 7,558	$ 3,257

Loans which are measured for impairment using the fair value of collaterals.

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- Definition

The valuation allowance on loans measured for impairment, using the fair value of collaterals.

+ References

No definition available.

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- Definition

Amount of unrealized gain (loss) on loans held for sale measured at fair value with change in fair value recognized in net income.

+ References

No definition available.

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Carrying amount of other real estate that are impaired, net reserves.

+ References

No definition available.

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- Definition

Amount of unrealized gain (loss) on capitalized servicing rights measured at fair value with change in fair value recognized in net income.

+ References

No definition available.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
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For each period for which an income statement is required, disclosure of the changes in the allowance, including balances at end of period.

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