Condensed Consolidated Statements of Changes in Stockholders' Equity - USD ($)	Common Stock [Member] Scenario, Previously Reported [Member]	Common Stock [Member]	Class C Special Stock [Member] Scenario, Previously Reported [Member]	Class C Special Stock [Member]	Additional Paid-in Capital [Member] Scenario, Previously Reported [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member] Scenario, Previously Reported [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Loss, Net of Tax [Member] Scenario, Previously Reported [Member]	Accumulated Other Comprehensive Loss, Net of Tax [Member]	(Accumulated Deficit)/Retained Earnings [Member] Scenario, Previously Reported [Member]	(Accumulated Deficit)/Retained Earnings [Member]	Scenario, Previously Reported [Member]	Total
Balance at Dec. 31, 2016		$ 1		$ 0		$ 172,563,000		$ 0		$ 0		$ (2,916,000)		$ 169,648,000
Balance (in shares) at Dec. 31, 2016		11,589						0
Stock-based Compensation Expense		$ 0		0		6,090,000		$ 0		0		0		6,090,000
Changes in Treasury Stock Related to Stock-based Compensation Arrangements		$ 0		0		0		$ (259,000)		0		0		(259,000)
Changes in Treasury Stock Related to Stock-based Compensation Arrangements (in shares)		0					0	5
Issuance of Common Shares upon Stock Option and ESPP Exercise		$ 0		0		353,000		$ 0		0		0		353,000
Issuance of Common Shares upon Stock Option and ESPP Exercise (in shares)		17						0
Issuance of Restricted Stock Awards		$ 0		0		0		$ 0		0		0		0
Issuance of Restricted Stock Awards (in shares)		50						0
Change in fair value of interest rate swap, net of tax														0
Net Income		$ 0		0		0		$ 0		0		(1,076,000)		(1,076,000)
Balance at Dec. 31, 2017	$ 1	$ 1	$ 0	0	$ 172,577,000	179,020,000	$ 0	$ (259,000)	$ 0	0	$ (2,930,000)	(4,006,000)	$ 169,648,000	174,756,000
Balance (in shares) at Dec. 31, 2017	11,589	11,656						5
Cumulative Effect of Change in Accounting Principle		$ 0		0		14,000		$ 0		0		(14,000)		0
Stock-based Compensation Expense		0		0		6,782,000		0		0		0		6,782,000
Changes in Treasury Stock Related to Stock-based Compensation Arrangements		$ 0		0		0		$ (659,000)		0		0		(659,000)
Changes in Treasury Stock Related to Stock-based Compensation Arrangements (in shares)		0						11
Issuance of Common Shares upon Stock Option and ESPP Exercise		$ 0		0		2,719,000		$ 259,000		0		0		2,978,000
Issuance of Common Shares upon Stock Option and ESPP Exercise (in shares)		142						(5)
Issuance of Restricted Stock Awards		$ 0		0		0		$ 0		0		0		0
Issuance of Restricted Stock Awards (in shares)		65						0
Repurchase of Convertible Notes and Unwind of Call Option Overlay		$ 0		0		(1,709,000)		$ 0		0		0		(1,709,000)
Change in fair value of interest rate swap, net of tax		0		0		0		0		(379,000)		0		(379,000)
Net Income		0		0		0		0		0		15,494,000		15,494,000
Balance at Dec. 31, 2018		$ 1		0		186,812,000		$ (659,000)		(379,000)		11,488,000		197,263,000
Balance (in shares) at Dec. 31, 2018		11,863						11
Stock-based Compensation Expense		$ 0		0		9,217,000		$ 0		0		0		9,217,000
Changes in Treasury Stock Related to Stock-based Compensation Arrangements		$ 0		0		0		$ (1,031,000)		0		0		(1,031,000)
Changes in Treasury Stock Related to Stock-based Compensation Arrangements (in shares)		0						20
Issuance of Common Shares upon Stock Option and ESPP Exercise		$ 0		0		5,738,000		$ 0		0		0		5,738,000
Issuance of Common Shares upon Stock Option and ESPP Exercise (in shares)		136						0
Issuance of Restricted Stock Awards		$ 0		0		(967,000)		$ 967,000		0		0		0
Issuance of Restricted Stock Awards (in shares)		106						(16)
Change in fair value of interest rate swap, net of tax		$ 0		0		0		$ 0		(4,492,000)		0		(4,492,000)
Net Income		0		0		0		0		0		6,094,000		6,094,000
Balance at Dec. 31, 2019		$ 1		0		200,800,000		$ (723,000)		(4,871,000)		17,584,000		212,791,000
Balance (in shares) at Dec. 31, 2019		12,105						15
Cumulative Effect of Change in Accounting Principle		$ 0		$ 0		$ 0		$ 0		$ 0		$ 2,000		$ 2,000