STOCKHOLDERS' EQUITY - Schedule of Share-based Compensation, Stock Options, Activity (Details) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) $ / shares shares
Shares
Outstanding at the beginning of the year (in Shares) | shares	1,494
Options granted (in Shares) | shares	721
Stock issued upon option exercise (in Shares) | shares	(143)
Canceled (in Shares) | shares	(387)
Outstanding at the end of the year (in Shares) | shares	1,685
Weighted Average Exercise Price
Outstanding at the beginning of the year (USD per Share) | $ / shares	$ 10.99
Granted (USD per Share) | $ / shares	6.50
Exercised (USD per Share) | $ / shares	5.65
Canceled (USD per Share) | $ / shares	10.17
Outstanding at the end of the year (USD per Share) | $ / shares	$ 9.71
Additional Disclosures
Outstanding weighted average remaining contractual term	3 years 1 month 6 days
Intrinsic value, options outstanding | $	$ 1,336
Vested and expected to vest (in Shares) | shares	1,424
Vested and expected to vest (in USD per Share) | $ / shares	$ 9.83
Vested and expected to vest weighted average remaining contractual term	3 years
Intrinsic value, options vested and expected to vest | $	$ 1,052
Options exercisable at the end of the year (in Shares) | shares	769
Options exercisable at the end of the year (USD per Share) | $ / shares	$ 10.43
Exercisable weighted average remaining contractual term	2 years 2 months 12 days
Intrinsic value, options exercisable | $	$ 350