Loans and Allowance for Loan Losses - Average Recorded Investment and Interest Income Recognized (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Impaired Loans
Average recorded investment in impaired loans	$ 12,117	$ 11,830	$ 4,338
Interest income recognized	534	528	183
Mortgage warehouse lines of credit
Impaired Loans
Average recorded investment in impaired loans	242	932
Interest income recognized		59
Residential real estate
Impaired Loans
Average recorded investment in impaired loans	3,175	1,485	156
Interest income recognized	71	50	1
Commercial and commercial real estate
Impaired Loans
Average recorded investment in impaired loans	8,675	8,872	3,703
Interest income recognized	463	375	182
Agricultural production and real estate
Impaired Loans
Average recorded investment in impaired loans		489	282
Interest income recognized		43
Consumer and margin loans
Impaired Loans
Average recorded investment in impaired loans	$ 25	52	$ 197
Interest income recognized		$ 1

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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 http://asc.fasb.org/extlink&oid=84173941&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 http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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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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