CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid in Capital	Accumulated deficit	Accumulated Other Comprehensive Loss	Treasury Stock
Beginning Balance (in shares) at Dec. 31, 2019		18,360,000				(1,731,000)
Beginning Balance at Dec. 31, 2019	$ 72,847	$ 367	$ 94,372	$ (10,144)	$ (5,368)	$ (6,380)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon the exercise of stock options (in shares)		2,000
Issuance of common stock upon the exercise of stock options	30		30
Net issuance of restricted stock awards (in shares)		21,000
Treasury stock acquired from employees upon vesting or forfeiture of restricted stock (in shares)						38,000
Treasury stock acquired from employees upon vesting or forfeiture of restricted stock	(524)					$ (524)
Issuance of restricted stock for acquisition (in shares)		908,000
Issuance of restricted stock for acquisition	19	$ 19
Equity component of redeemed 2024 convertible notes (in shares)						(722,000)
Equity component of redeemed 2024 convertible notes	(5,553)		(7,988)			$ 2,435
Equity component of issued 2026 convertible notes	19,097		19,097
Stock-based compensation	1,089		1,089
Foreign currency translation adjustments	201				201
Net loss	(10,910)			(10,910)
Ending Balance (in shares) at Mar. 31, 2020		19,291,000				(1,047,000)
Ending Balance at Mar. 31, 2020	$ 76,296	$ 386	106,600	(21,054)	(5,167)	$ (4,469)
Beginning Balance (in shares) at Dec. 31, 2020	21,917,357	22,983,000				(1,066,000)
Beginning Balance at Dec. 31, 2020	$ 188,405	$ 459	243,575	(46,706)	(3,936)	$ (4,987)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon the exercise of stock options (in shares)	34,000	34,000
Issuance of common stock upon the exercise of stock options	$ 409	$ 1	408
Net issuance of restricted stock awards (in shares)		87,000
Net issuance of restricted stock awards	265	$ 2	263
Treasury stock acquired from employees upon vesting or forfeiture of restricted stock (in shares)						76,000
Treasury stock acquired from employees upon vesting or forfeiture of restricted stock	(3,974)					$ (3,974)
Stock-based compensation	1,320		1,320
Foreign currency translation adjustments	(302)				(302)
Net loss	$ (8,271)			(8,271)
Ending Balance (in shares) at Mar. 31, 2021	21,961,788	23,104,000				(1,142,000)
Ending Balance at Mar. 31, 2021	$ 177,852	$ 462	$ 245,566	$ (54,977)	$ (4,238)	$ (8,961)