Loans and Allowance for Credit Losses on Loans - Average Recorded Investment and Interest Income Recognized (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Impaired Loans
Average recorded investment in impaired loans	$ 23,302	$ 14,700
Interest income recognized	461	429
Mortgage warehouse lines of credit
Impaired Loans
Average recorded investment in impaired loans		106
Residential real estate
Impaired Loans
Average recorded investment in impaired loans	1,658	3,002
Interest income recognized	64	57
Multi-family financing
Impaired Loans
Average recorded investment in impaired loans	14,138
Commercial and commercial real estate
Impaired Loans
Average recorded investment in impaired loans	6,888	9,913
Interest income recognized	397	371
Agricultural production and real estate
Impaired Loans
Average recorded investment in impaired loans	611	1,662
Interest income recognized		1
Consumer and margin loans
Impaired Loans
Average recorded investment in impaired loans	$ 7	$ 17

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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5258-111524

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- Definition

Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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