Loans and Allowance for Loan Losses - Loans modified as troubled debt restructurings (Details 8)	12 Months Ended
Dec. 31, 2016 USD ($) Loan	Dec. 31, 2015 USD ($) Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings, number of modifications \| Loan	3	9
Troubled debt restructurings, recorded investment \| $	$ 967,042	$ 700,800
Real estate loans \| 1-4 family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings, number of modifications \| Loan	1	1
Troubled debt restructurings, recorded investment \| $	$ 40,395	$ 98,246
Real estate loans \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings, number of modifications \| Loan	1	2
Troubled debt restructurings, recorded investment \| $	$ 708,922	$ 524,432
Real estate loans \| Agricultural real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings, number of modifications \| Loan
Troubled debt restructurings, recorded investment \| $
Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings, number of modifications \| Loan	1
Troubled debt restructurings, recorded investment \| $	$ 217,725
Agricultural loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings, number of modifications \| Loan
Troubled debt restructurings, recorded investment \| $
Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings, number of modifications \| Loan		1
Troubled debt restructurings, recorded investment \| $		$ 1,431
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings, number of modifications \| Loan		5
Troubled debt restructurings, recorded investment \| $		$ 76,691

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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