Loans and Allowance for Loan Losses - Average Recorded Investment and Interest Income Recognized (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Impaired Loans
Average recorded investment in impaired loans	$ 3,646	$ 3,148	$ 3,831	$ 1,480
Interest income recognized	11	10	21	10
Residential real estate
Impaired Loans
Average recorded investment in impaired loans	231	134	274	96
Commercial and commercial real estate
Impaired Loans
Average recorded investment in impaired loans	3,133	3,014	3,275	1,384
Interest income recognized	11	$ 10	21	$ 10
Agricultural production and real estate
Impaired Loans
Average recorded investment in impaired loans	$ 282		$ 282

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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://www.xbrl.org/2003/role/presentationRef
-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://www.xbrl.org/2003/role/presentationRef
-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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