LOANS - Recorded Investment and Number of Modifications (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) modification	Dec. 31, 2016 USD ($) modification	Dec. 31, 2015 USD ($) modification
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Modifications (in modification) \| modification	18	13	10
Pre-Modification Outstanding Recorded Investment	$ 1,713	$ 1,537	$ 1,795
Post-Modification Outstanding Recorded Investment	$ 1,504	$ 1,457	$ 1,800
Commercial and Industrial: \| Commercial installment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Modifications (in modification) \| modification	6	6	4
Pre-Modification Outstanding Recorded Investment	$ 388	$ 1,459	$ 342
Post-Modification Outstanding Recorded Investment	$ 222	$ 1,354	$ 352
Commercial and Industrial: \| Agricultural and other loans to farmers
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Modifications (in modification) \| modification	6	2	0
Pre-Modification Outstanding Recorded Investment	$ 563	$ 38	$ 0
Post-Modification Outstanding Recorded Investment	$ 545	$ 48	$ 0
Commercial Real Estate: \| Other commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Modifications (in modification) \| modification	1	3	1
Pre-Modification Outstanding Recorded Investment	$ 19	$ 29	$ 18
Post-Modification Outstanding Recorded Investment	$ 18	$ 44	$ 15
Residential Real Estate: \| Residential mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Modifications (in modification) \| modification	3	0	0
Pre-Modification Outstanding Recorded Investment	$ 692	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	$ 670	$ 0	$ 0
Consumer: \| Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Modifications (in modification) \| modification	1	0	0
Pre-Modification Outstanding Recorded Investment	$ 13	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	$ 13	$ 0	$ 0
Consumer: \| Other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Modifications (in modification) \| modification	1	2	5
Pre-Modification Outstanding Recorded Investment	$ 38	$ 11	$ 1,435
Post-Modification Outstanding Recorded Investment	$ 36	$ 11	$ 1,433

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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=84173941&loc=SL6953676-111524

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