CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (UNAUDITED) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Balance at the beginning of period (in shares) at Dec. 31, 2018		6,627,358
Balance in the beginning of period at Dec. 31, 2018	$ 193,703	$ 41,094	$ 1,042	$ 159,073	$ (7,506)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	5,696			5,696
Stock incentive plan	49		49
Issuance of shares of common stock through exercise of stock options (in shares)		7,200
Issuance of shares of common stock through exercise of stock options	80	$ 80
Issuance of shares of common stock as board compensation (in shares)		2,368
Issuance of shares of common stock as board compensation	97	$ 97
Cash dividend	(1,326)			(1,326)
Other comprehensive income (loss)	3,885				3,885
Balance at the end of period (in shares) at Mar. 31, 2019		6,636,926
Balance at the end of period at Mar. 31, 2019	202,184	$ 41,271	1,091	163,443	(3,621)
Balance at the beginning of period (in shares) at Dec. 31, 2018		6,627,358
Balance in the beginning of period at Dec. 31, 2018	193,703	$ 41,094	1,042	159,073	(7,506)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	18,081
Other comprehensive income (loss)	7,780
Balance at the end of period (in shares) at Sep. 30, 2019		7,306,221
Balance at the end of period at Sep. 30, 2019	245,389	$ 68,082	1,205	175,828	274
Balance at the beginning of period (in shares) at Mar. 31, 2019		6,636,926
Balance in the beginning of period at Mar. 31, 2019	202,184	$ 41,271	1,091	163,443	(3,621)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	5,538			5,538
Stock incentive plan	50		50
Issuance of shares of common stock through IPO (in shares)		663,320
Issuance of shares of common stock through IPO	26,812	$ 26,812
Board compensation adjustment	(1)	$ (1)
Other comprehensive income (loss)	3,328				3,328
Balance at the end of period (in shares) at Jun. 30, 2019		7,300,246
Balance at the end of period at Jun. 30, 2019	237,911	$ 68,082	1,141	168,981	(293)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	6,847			6,847
Stock incentive plan	64		64
Issuance of restricted shares of common stock through stock incentive plan, net (in shares)		5,975
Issuance of restricted shares of common stock through stock incentive plan, net	0
Other comprehensive income (loss)	567				567
Balance at the end of period (in shares) at Sep. 30, 2019		7,306,221
Balance at the end of period at Sep. 30, 2019	$ 245,389	$ 68,082	1,205	175,828	274
Balance at the beginning of period (in shares) at Dec. 31, 2019	7,306,221	7,306,221
Balance in the beginning of period at Dec. 31, 2019	$ 251,898	$ 68,082	1,269	182,571	(24)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	6,745			6,745
Stock incentive plan	64		64
Issuance of shares of common stock through exercise of stock options (in shares)		14,720
Issuance of shares of common stock through exercise of stock options	8	$ 8
Issuance of shares of common stock as board compensation (in shares)		1,591
Issuance of shares of common stock as board compensation	87	$ 87
Cash dividend	(439)			(439)
Other comprehensive income (loss)	5,812				5,812
Balance at the end of period (in shares) at Mar. 31, 2020		7,322,532
Balance at the end of period at Mar. 31, 2020	$ 264,175	$ 68,177	1,333	188,877	5,788
Balance at the beginning of period (in shares) at Dec. 31, 2019	7,306,221	7,306,221
Balance in the beginning of period at Dec. 31, 2019	$ 251,898	$ 68,082	1,269	182,571	(24)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	20,884
Other comprehensive income (loss)	$ 6,424
Balance at the end of period (in shares) at Sep. 30, 2020	7,306,221	7,325,333
Balance at the end of period at Sep. 30, 2020	$ 278,078	$ 68,055	1,487	202,136	6,400
Balance at the beginning of period (in shares) at Mar. 31, 2020		7,322,532
Balance in the beginning of period at Mar. 31, 2020	264,175	$ 68,177	1,333	188,877	5,788
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	6,854			6,854
Stock incentive plan	96		96
Cash dividend	(440)			(440)
Other comprehensive income (loss)	432				432
Balance at the end of period (in shares) at Jun. 30, 2020		7,322,532
Balance at the end of period at Jun. 30, 2020	271,117	$ 68,177	1,429	195,291	6,220
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	7,285			7,285
Stock incentive plan	58		58
Cash dividend	(440)			(440)
Issuance of restricted shares of common stock through stock incentive plan, net (in shares)		5,625
Issuance of restricted shares of common stock through stock incentive plan, net	$ 0
Purchase of common stock under stock buyback program (in shares)	(2,824)	(2,824)
Purchase of common stock under stock repurchase program	$ (122)	$ (122)
Other comprehensive income (loss)	$ 180				180
Balance at the end of period (in shares) at Sep. 30, 2020	7,306,221	7,325,333
Balance at the end of period at Sep. 30, 2020	$ 278,078	$ 68,055	$ 1,487	$ 202,136	$ 6,400