Condensed Consolidated Statements of Changes in Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Common Stock [Member]	Class C Special Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Loss, Net of Tax [Member]	Retained Earnings [Member]	Total
Balance at Dec. 31, 2018	$ 1	$ 0	$ 186,812	$ (659)	$ (379)	$ 11,488	$ 197,263
Balance (in shares) at Dec. 31, 2018	11,863			11
Cumulative Effect on Retained Earnings, net of tax	$ 0	0	0	$ 0	0	2	2
Stock-based Compensation Expense	0	0	4,303	0	0	0	4,303
Treasury stock purchases for restricted stock vests	0	0	0	$ (1,031)	0	0	(1,031)
Treasury stock purchases for restricted stock vests (in shares)				17
Issuance of Common Shares upon Stock Option and ESPP Exercise	$ 0	0	4,719	$ 0	0	0	4,719
Issuance of Common Shares upon Stock Option and ESPP Exercise (in shares)	117			(16)
Issuance of Restricted Stock Awards	$ 0	0	(967)	$ 967	0	0	0
Issuance of Restricted Stock Awards (in shares)	106
Change in Fair Value of Interest Rate Swap, Net of Tax	$ 0	0	0	0	(4,634)	0	(4,634)
Net (Loss)/Income	0	0	0	0	0	7,034	7,034
Balance at Jun. 30, 2019	$ 1	0	194,867	$ (723)	(5,013)	18,524	207,656
Balance (in shares) at Jun. 30, 2019	12,086			12
Balance at Mar. 31, 2019	$ 1		189,971		(2,199)	11,939	199,712
Balance (in shares) at Mar. 31, 2019	12,024			2
Stock-based Compensation Expense			2,593				2,593
Treasury stock purchases for restricted stock vests				$ (723)			(723)
Treasury stock purchases for restricted stock vests (in shares)				10
Issuance of Common Shares upon Stock Option and ESPP Exercise			2,303				2,303
Issuance of Common Shares upon Stock Option and ESPP Exercise (in shares)	62
Change in Fair Value of Interest Rate Swap, Net of Tax					(2,814)		(2,814)
Net (Loss)/Income						6,585	6,585
Balance at Jun. 30, 2019	$ 1	0	194,867	$ (723)	(5,013)	18,524	207,656
Balance (in shares) at Jun. 30, 2019	12,086			12
Balance at Dec. 31, 2019	$ 1	0	200,800	$ (723)	(4,871)	17,584	212,791
Balance (in shares) at Dec. 31, 2019	12,105			15
Cumulative Effect on Retained Earnings, net of tax	$ 0	0	0	$ 0	0	(8)	(8)
Stock-based Compensation Expense	0	0	8,160	0	0	0	8,160
Treasury stock purchases for restricted stock vests	0	0	0	$ (1,523)	0	0	(1,523)
Treasury stock purchases for restricted stock vests (in shares)				43
Issuance of Common Shares upon Stock Option and ESPP Exercise	$ 0	0	449	$ 0	0	0	449
Issuance of Common Shares upon Stock Option and ESPP Exercise (in shares)	14
Issuance of Restricted Stock Awards	$ 0	0	0	0	0	0	0
Issuance of Restricted Stock Awards (in shares)	261
Change in Fair Value of Interest Rate Swap, Net of Tax	$ 0	0	0	0	(9,178)	0	(9,178)
Net (Loss)/Income	0	0	0	0	0	(19,347)	(19,347)
Balance at Jun. 30, 2020	$ 1	0	209,409	$ (2,246)	(14,049)	(1,771)	191,344
Balance (in shares) at Jun. 30, 2020	12,380			58
Balance at Mar. 31, 2020	$ 1		203,505	$ (1,211)	(11,689)	10,565	201,171
Balance (in shares) at Mar. 31, 2020	12,112			28
Stock-based Compensation Expense			5,736				5,736
Treasury stock purchases for restricted stock vests				$ (1,035)			(1,035)
Treasury stock purchases for restricted stock vests (in shares)				30
Issuance of Common Shares upon Stock Option and ESPP Exercise			168				168
Issuance of Common Shares upon Stock Option and ESPP Exercise (in shares)	7
Issuance of Restricted Stock Awards (in shares)	261
Change in Fair Value of Interest Rate Swap, Net of Tax					(2,360)		(2,360)
Net (Loss)/Income						(12,336)	(12,336)
Balance at Jun. 30, 2020	$ 1	$ 0	$ 209,409	$ (2,246)	$ (14,049)	$ (1,771)	$ 191,344
Balance (in shares) at Jun. 30, 2020	12,380			58