Consolidated Statements of Income - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Interest and Dividend Income
Loans receivable	$ 73,623,000	$ 68,474,000	$ 51,231,000
Investment securities	10,723,000	10,363,000	7,037,000
Federal Home Loan Bank stock	692,000	606,000	470,000
Deposits with financial institutions	291,000	251,000	130,000
Total interest and dividend income	85,329,000	79,694,000	58,868,000
Interest Expense
Deposits	15,119,000	10,856,000	6,815,000
Federal Home Loan Bank advances	4,950,000	4,869,000	3,604,000
Other	963,000	866,000	192,000
Total interest expense	21,032,000	16,591,000	10,611,000
Net Interest Income	64,297,000	63,103,000	48,257,000
Provision for loan losses	1,950,000	2,120,000	1,220,000
Net Interest Income After Provision for Loan Losses	62,347,000	60,983,000	47,037,000
Non-interest Income
Net realized gain on sales of available for sale securities	1,014,000	804,000	708,000
Net gains on sales of loans	5,871,000	3,126,000	3,887,000
Net servicing fees	595,000	591,000	391,000
Increase in cash value of life insurance	1,239,000	1,239,000	1,113,000
Loss on sale of other real estate and repossessed assets	(19,000)	(43,000)	(122,000)
Other income	2,485,000	1,055,000	488,000
Total non-interest income	24,921,000	19,574,000	18,076,000
Non-interest Expenses
Salaries and employee benefits	36,313,000	32,964,000	27,229,000
Net occupancy expenses	4,055,000	3,965,000	3,133,000
Equipment expenses	2,441,000	2,514,000	1,773,000
Data processing fees	2,613,000	2,624,000	2,321,000
ATM and debit card expenses	2,334,000	2,290,000	1,676,000
Deposit insurance	413,000	898,000	724,000
Professional fees	2,706,000	2,177,000	1,855,000
Advertising and promotion	1,323,000	1,606,000	1,223,000
Software subscriptions and maintenance	3,014,000	2,719,000	2,202,000
Intangible amortization	779,000	1,103,000	264,000
Other real estate and repossessed assets	256,000	189,000	165,000
Other expenses	4,911,000	5,684,000	3,440,000
Total non-interest expenses	61,158,000	58,733,000	46,005,000
Income Before Income Tax	26,110,000	21,824,000	19,108,000
Income tax expense	2,359,000	2,960,000	6,793,000
Net Income	$ 23,751,000	$ 18,864,000	$ 12,315,000
Earnings Per Common Share
Basic	$ 2.77	$ 2.25	$ 1.67
Diluted	2.74	2.21	1.64
Dividends Per Common Share	$ 0.80	$ 0.74	$ 0.66
Service Fees [Member]
Non-interest Income
Non-interest income	$ 8,949,000	$ 7,937,000	$ 6,584,000
Commissions [Member]
Non-interest Income
Non-interest income	$ 4,787,000	$ 4,865,000	$ 5,027,000