Changes in allowance for loan losses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Residential 1-4 family
Financing Receivable, Past Due [Line Items]
Beginning balance	$ 2,846	$ 2,646	$ 2,393
Provision	822	225	255
Charge-offs	(73)	(44)	(11)
Recoveries	27	19	9
Ending balance	3,622	2,846	2,646
Recoveries	(27)	(19)	(9)
Residential 5+ multifamily
Financing Receivable, Past Due [Line Items]
Beginning balance	817	686	446
Provision	779	131	282
Charge-offs	(231)		(42)
Recoveries
Ending balance	1,365	817	686
Recoveries
Construction of residential 1-4 family
Financing Receivable, Past Due [Line Items]
Beginning balance	186	65	75
Provision	42	121	(10)
Charge-offs	(25)
Recoveries
Ending balance	203	186	65
Recoveries
Home equity lines of credit
Financing Receivable, Past Due [Line Items]
Beginning balance	198	252	197
Provision	53	(34)	(197)
Charge-offs	(11)	(21)
Recoveries		1	252
Ending balance	240	198	252
Recoveries		(1)	(252)
Residential real estate
Financing Receivable, Past Due [Line Items]
Beginning balance	4,047	3,649	3,111
Provision	1,696	443	330
Charge-offs	(340)	(65)	(53)
Recoveries	27	20	261
Ending balance	5,430	4,047	3,649
Recoveries	(27)	(20)	(261)
Commercial
Financing Receivable, Past Due [Line Items]
Beginning balance	5,416	6,546	3,742
Provision	907	(1,260)	2,776
Charge-offs	(372)	(6)	(17)
Recoveries	1	136	45
Ending balance	5,952	5,416	6,546
Recoveries	(1)	(136)	(45)
Construction of commercial
Financing Receivable, Past Due [Line Items]
Beginning balance	1,025	596	104
Provision	(309)	447	492
Charge-offs		(18)
Recoveries
Ending balance	716	1,025	596
Recoveries
Commercial real estate
Financing Receivable, Past Due [Line Items]
Beginning balance	6,441	7,142	3,846
Provision	598	(813)	3,268
Charge-offs	(372)	(24)	(17)
Recoveries	1	136	45
Ending balance	6,668	6,441	7,142
Recoveries	(1)	(136)	(45)
Farm land
Financing Receivable, Past Due [Line Items]
Beginning balance	21	59	47
Provision	9	(39)	12
Charge-offs		(2)
Recoveries		3
Ending balance	30	21	59
Recoveries		(3)
Vacant land
Financing Receivable, Past Due [Line Items]
Beginning balance	95	180	71
Provision	(4)	(86)	109
Charge-offs
Recoveries		1
Ending balance	91	95	180
Recoveries		(1)
Real estate secured
Financing Receivable, Past Due [Line Items]
Beginning balance	10,604	11,030	7,075
Provision	2,299	(495)	3,719
Charge-offs	(712)	(91)	(70)
Recoveries	28	160	306
Ending balance	12,219	10,604	11,030
Recoveries	(28)	(160)	(306)
Commercial and industrial
Financing Receivable, Past Due [Line Items]
Beginning balance	1,364	1,397	1,145
Provision	31	45	612
Charge-offs	(46)	(131)	(362)
Recoveries	1	53	2
Ending balance	1,350	1,364	1,397
Recoveries	(1)	(53)	(2)
Municipal
Financing Receivable, Past Due [Line Items]
Beginning balance	31	43	46
Provision	28	(12)	(3)
Charge-offs
Recoveries
Ending balance	59	31	43
Recoveries
Consumer
Financing Receivable, Past Due [Line Items]
Beginning balance	82	77	60
Provision	111	68	72
Charge-offs	(88)	(59)	(70)
Recoveries	18	4	15
Ending balance	123	82	77
Recoveries	(18)	(4)	(15)
Unallocated
Financing Receivable, Past Due [Line Items]
Beginning balance	881	1,207	569
Provision	214	(326)	638
Charge-offs
Recoveries
Ending balance	1,095	881	1,207
Recoveries
Totals
Financing Receivable, Past Due [Line Items]
Beginning balance	12,962	13,754	8,895
Provision	2,683	(720)	5,038
Charge-offs	(846)	(281)	(502)
Recoveries	47	209	323
Ending balance	14,846	12,962	13,754
Recoveries	$ (47)	$ (209)	$ (323)