Consolidated Statement of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning Balance, shares at Dec. 31, 2018		(24,418,252)	(2,671,962)
Beginning Balance at Dec. 31, 2018	$ 540,624	$ 244	$ (124,794)	$ 452,573	$ 196,106	$ 16,495
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	33,499				27,430	6,069
Issuance of common stock in connection with:
Restricted stock awards, net of cancellations, shares		331,105	21,433
Restricted stock awards, net of cancellations	0	$ 4	$ 1,952	(1,956)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period		30,000
Stock Issued During Period, Value, Stock Options Exercised	703	$ 0		703
Share-based compensation	17,937			17,937
Shares redeemed for employee tax withholdings, shares			(108,695)
Shares redeemed for employee tax withholdings	(5,206)		$ 5,206
Ending Balance, shares at Sep. 30, 2019		(24,779,357)	(2,759,224)
Ending Balance at Sep. 30, 2019	587,557	$ 248	$ (128,048)	469,257	223,536	22,564
Beginning Balance, shares at Jun. 30, 2019		(24,711,193)	(2,742,826)
Beginning Balance at Jun. 30, 2019	568,361	$ 247	$ (127,133)	463,190	209,882	22,175
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	14,043				13,654	389
Issuance of common stock in connection with:
Restricted stock awards, net of cancellations, shares		58,164	(3,741)
Restricted stock awards, net of cancellations	0	$ 1	$ (169)	168
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period		10,000
Stock Issued During Period, Value, Stock Options Exercised	235	$ 0		235
Share-based compensation	5,664			5,664
Shares redeemed for employee tax withholdings, shares			(12,657)
Shares redeemed for employee tax withholdings	(746)		$ 746
Ending Balance, shares at Sep. 30, 2019		(24,779,357)	(2,759,224)
Ending Balance at Sep. 30, 2019	587,557	$ 248	$ (128,048)	469,257	223,536	22,564
Beginning Balance, shares at Dec. 31, 2019		(24,603,308)	(2,763,302)
Beginning Balance at Dec. 31, 2019	585,465	$ 247	$ (128,348)	460,781	237,849	14,936
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	(22,681)				(17,703)	(4,978)
Issuance of common stock in connection with:
Restricted stock awards, net of cancellations, shares		321,986	94,180
Restricted stock awards, net of cancellations	0	$ 3	$ 6,707	(6,710)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period		33,600
Stock Issued During Period, Value, Stock Options Exercised	825	$ 0		825
Share-based compensation	20,135			20,135
Shares redeemed for employee tax withholdings, shares			(134,274)
Shares redeemed for employee tax withholdings	(7,797)		$ 7,797
Stock Repurchased and Retired During Period, Shares		(313,998)
Stock Repurchased and Retired During Period, Value	(20,881)	$ (3)		(20,878)
Ending Balance, shares at Sep. 30, 2020		(24,644,896)	(2,803,396)
Ending Balance at Sep. 30, 2020	555,066	$ 247	$ (129,438)	454,153	220,146	9,958
Beginning Balance, shares at Jun. 30, 2020		(24,586,236)	(2,786,798)
Beginning Balance at Jun. 30, 2020	536,014	$ 246	$ (128,646)	450,391	209,088	4,935
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	16,081				11,058	5,023
Issuance of common stock in connection with:
Restricted stock awards, net of cancellations, shares		51,860	(4,130)
Restricted stock awards, net of cancellations	0	$ 1	$ (212)	211
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period		6,800
Stock Issued During Period, Value, Stock Options Exercised	179	$ 0		179
Share-based compensation	3,372			3,372
Shares redeemed for employee tax withholdings, shares			(12,468)
Shares redeemed for employee tax withholdings	(580)		$ 580
Ending Balance, shares at Sep. 30, 2020		(24,644,896)	(2,803,396)
Ending Balance at Sep. 30, 2020	$ 555,066	$ 247	$ (129,438)	$ 454,153	$ 220,146	$ 9,958