Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning balance (in shares) at Dec. 31, 2020		28,556,605
Beginning balance at Dec. 31, 2020	$ 917,160	$ 29	$ 510,158	$ 408,037	$ (1,064)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	60,478			60,478
Unrealized gain (loss) on investment, net of tax effect	185				185
Adjustment to pension benefit plans, net of taxes	716				716
Share-based compensation	4,128		4,246	(118)
Issuance of restricted and deferred stock units (in shares)		49,824
Issuance of restricted and deferred stock units	$ (1,066)		(1,066)
Employee stock purchase plan (in shares)	35,304	35,304
Employee stock purchase plan	$ 2,026		2,026
Common stock issuance, net of costs (in shares)		1,539,615
Common stock issuance, net of costs	91,029	$ 1	91,028
Dividends paid	(40,137)			(40,137)
Ending balance (in shares) at Dec. 31, 2021		30,181,348
Ending balance at Dec. 31, 2021	1,034,519	$ 30	606,392	428,260	(163)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	73,828			73,828
Unrealized gain (loss) on investment, net of tax effect	(511)				(511)
Adjustment to pension benefit plans, net of taxes	2,151				2,151
Share-based compensation	4,641		4,791	(150)
Issuance of restricted and deferred stock units (in shares)		54,243
Issuance of restricted and deferred stock units	$ (1,354)		(1,354)
Employee stock purchase plan (in shares)	36,585	36,585
Employee stock purchase plan	$ 2,091		2,091
Common stock issuance, net of costs (in shares)		529,736
Common stock issuance, net of costs	39,085	$ 1	39,084
Dividends paid	$ (43,582)			(43,582)
Ending balance (in shares) at Dec. 31, 2022	30,801,912	30,801,912
Ending balance at Dec. 31, 2022	$ 1,110,868	$ 31	651,004	458,356	1,477
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	84,987			84,987
Unrealized gain (loss) on investment, net of tax effect	530				530
Adjustment to pension benefit plans, net of taxes	(216)				(216)
Share-based compensation	4,592		4,647	(55)
Issuance of restricted and deferred stock units (in shares)		67,164
Issuance of restricted and deferred stock units	$ (2,259)		(2,259)
Employee stock purchase plan (in shares)	34,122	34,122
Employee stock purchase plan	$ 2,141		2,141
Common stock issuance, net of costs (in shares)		1,119,806
Common stock issuance, net of costs	80,659	$ 1	80,658
Dividends paid	$ (47,905)			(47,905)
Ending balance (in shares) at Dec. 31, 2023	32,023,004	32,023,004
Ending balance at Dec. 31, 2023	$ 1,233,397	$ 32	$ 736,191	$ 495,383	$ 1,791