GOODWILL AND OTHER INTANGIBLE ASSETS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Oct. 01, 2018	May 31, 2018	May 18, 2018	Aug. 31, 2016	Apr. 29, 2016	Dec. 05, 2014
Goodwill	$ 22,024	$ 5,694	$ 22,024
Deposit based intangible assets	5,720	1,922	6,746
Amortization expense	450	249
Future Amortization Expense	675
Amortization expense year one	675
Amortization expense year two	675
Amortization expense year three	675
Amortization expense year four	675
Amortization expense year five	675
PFC
Goodwill								$ 3,805
Deposit based intangible assets	714	835						$ 1,206
Amortization expense	121	120
Future Amortization Expense	121
Eagle River
Goodwill							$ 1,839
Deposit based intangible assets	728	827					$ 993
Amortization expense	99	99
Future Amortization Expense	99
Niagara Bancorporation
Goodwill						$ 50
Deposit based intangible assets	230	260				$ 300
Amortization expense	30	$ 30
Future Amortization Expense	30
FFNM
Goodwill				$ 14,915	$ 14,915
Deposit based intangible assets	2,735				$ 2,894
Amortization expense	159
Future Amortization Expense	290
Lincoln Community Bank
Goodwill			1,415
Deposit based intangible assets	1,313		$ 1,353
Amortization expense	41
Future Amortization Expense	$ 135