CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (UNAUDITED) - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Additional Paid In Capital	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Treasury Stock	Accumulated  Other Comprehensive Loss
BEGINNING BALANCE (in shares) at Dec. 31, 2019			32,871,504
BEGINNING BALANCE at Dec. 31, 2019	$ 250,031	$ (1,190)	$ 329	$ 190,230	$ 173,371	$ (1,190)		$ (7,143)
BEGINING BALANCE, Treasury Stock (in shares) at Dec. 31, 2019							(2,855,164)
BEGINING BALANCE, Treasury Stock at Dec. 31, 2019							$ (106,756)
Net income	41,325				41,325
Issuance of common stock awards to employees (in shares)			246,362
Issuance of common stock awards to employees	0		$ 2	(2)
Surrender of common stock awards (in shares)							(27,343)
Surrender of common stock awards	(973)						$ (973)
Share-based compensation expense	4,935			4,935
Share-based compensation issued to directors (in shares)			6,371
Share-based compensation issued to directors	$ 125			125
Common stock repurchase (in shares)	(443,000)						(442,542)
Common stock repurchase	$ (15,759)						$ (15,759)
Other comprehensive income (loss), net of tax	(5,758)							(5,758)
ENDING BALANCE (in shares) at Jun. 30, 2020			33,124,237
ENDING BALANCE at Jun. 30, 2020	272,736		$ 331	195,288	213,506			(12,901)
ENDING BALANCE, Treasury Stock (in shares) at Jun. 30, 2020							(3,325,049)
ENDING BALANCE, Treasury Stock at Jun. 30, 2020							$ (123,488)
BEGINNING BALANCE (in shares) at Mar. 31, 2020			32,961,777
BEGINNING BALANCE at Mar. 31, 2020	245,797		$ 330	192,564	188,169			(12,751)
BEGINING BALANCE, Treasury Stock (in shares) at Mar. 31, 2020							(3,299,465)
BEGINING BALANCE, Treasury Stock at Mar. 31, 2020							$ (122,515)
Net income	25,337				25,337
Issuance of common stock awards to employees (in shares)			156,405
Issuance of common stock awards to employees	0		$ 1	(1)
Surrender of common stock awards (in shares)							(25,584)
Surrender of common stock awards	(973)						$ (973)
Share-based compensation expense	2,633			2,633
Share-based compensation issued to directors (in shares)			6,055
Share-based compensation issued to directors	92			92
Other comprehensive income (loss), net of tax	(150)							(150)
ENDING BALANCE (in shares) at Jun. 30, 2020			33,124,237
ENDING BALANCE at Jun. 30, 2020	$ 272,736		$ 331	195,288	213,506			(12,901)
ENDING BALANCE, Treasury Stock (in shares) at Jun. 30, 2020							(3,325,049)
ENDING BALANCE, Treasury Stock at Jun. 30, 2020							$ (123,488)
BEGINNING BALANCE (in shares) at Dec. 31, 2020	33,141,879		33,141,879
BEGINNING BALANCE at Dec. 31, 2020	$ 319,182		$ 331	199,847	269,420			(8,763)
BEGINING BALANCE, Treasury Stock (in shares) at Dec. 31, 2020	(3,518,607)						(3,518,607)
BEGINING BALANCE, Treasury Stock at Dec. 31, 2020	$ (141,653)						$ (141,653)
Net income	54,504				54,504
Issuance of common stock awards to employees (in shares)			118,408
Issuance of common stock awards to employees	0		$ 2	(2)
Surrender of common stock awards (in shares)							(44,335)
Surrender of common stock awards	(5,551)						$ (5,551)
Share-based compensation expense	5,539			5,539
Share-based compensation issued to directors (in shares)			4,230
Share-based compensation issued to directors	213			213
Dividends declared	$ (17,817)				(17,817)
Common stock repurchase (in shares)	0
Other comprehensive income (loss), net of tax	$ 6,470							6,470
ENDING BALANCE (in shares) at Jun. 30, 2021	33,264,517		33,264,517
ENDING BALANCE at Jun. 30, 2021	$ 362,540		$ 333	205,597	306,107			(2,293)
ENDING BALANCE, Treasury Stock (in shares) at Jun. 30, 2021	(3,562,942)						(3,562,942)
ENDING BALANCE, Treasury Stock at Jun. 30, 2021	$ (147,204)						$ (147,204)
BEGINNING BALANCE (in shares) at Mar. 31, 2021			33,208,082
BEGINNING BALANCE at Mar. 31, 2021	340,538		$ 331	202,662	277,804			1,394
BEGINING BALANCE, Treasury Stock (in shares) at Mar. 31, 2021							(3,518,881)
BEGINING BALANCE, Treasury Stock at Mar. 31, 2021							$ (141,653)
Net income	37,213				37,213
Issuance of common stock awards to employees (in shares)			52,205
Issuance of common stock awards to employees	0		$ 2	(2)
Surrender of common stock awards (in shares)							(44,061)
Surrender of common stock awards	(5,551)						$ (5,551)
Share-based compensation expense	2,826			2,826
Share-based compensation issued to directors (in shares)			4,230
Share-based compensation issued to directors	111			111
Dividends declared	(8,910)				(8,910)
Other comprehensive income (loss), net of tax	$ (3,687)							(3,687)
ENDING BALANCE (in shares) at Jun. 30, 2021	33,264,517		33,264,517
ENDING BALANCE at Jun. 30, 2021	$ 362,540		$ 333	$ 205,597	$ 306,107			$ (2,293)
ENDING BALANCE, Treasury Stock (in shares) at Jun. 30, 2021	(3,562,942)						(3,562,942)
ENDING BALANCE, Treasury Stock at Jun. 30, 2021	$ (147,204)						$ (147,204)