STOCK-BASED COMPENSATION - Stock Options Activity (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Shares
Options exercised (in shares)		(278,000)
Employee Stock Option | The 2004 Plan
Shares
Options outstanding at the beginning of the period (in shares)	1,169,412
Options granted (in shares)	0
Options exercised (in shares)	(13,691)
Options forfeited (in shares)	0
Options expired (in shares)	(810,515)
Options outstanding at the end of the period (in shares)	345,206	1,169,412
Options vested and expected to vest at the end of the period (in shares)	345,206
Options exercisable at the end of the period (in shares)	345,206
Weighted- Average Exercise Price
Options outstanding at the beginning of the period (in dollars per share)	$ 7.57
Options granted (in dollars per share)	0.00
Options exercised (in dollars per share)	1.83
Options forfeited (in dollars per share)	0.00
Options expired (in dollars per share)	0.00
Options outstanding at the end of the period (in dollars per share)	7.29	$ 7.57
Options vested and expected to vest at the end of the period (in dollars per share)	7.29
Options exercisable at the end of the period (in dollars per share)	$ 7.29
Weighted- Average Remaining Contractual Term (years)
Options outstanding at the end of the period	2 years 6 months 29 days
Options vested and expected to vest at the end of the period	2 years 6 months 29 days
Options exercisable at the end of the period	2 years 6 months 29 days
Aggregate Intrinsic Value (in thousands)
Options outstanding at the end of the period	$ 0
Options vested and expected to vest at the end of the period	0.00
Options exercisable at the end of the period	$ 0
Employee Stock Option | The 2014 Plan
Shares
Options outstanding at the beginning of the period (in shares)	1,461,469
Options granted (in shares)	0
Options exercised (in shares)	0
Options forfeited (in shares)	(102,669)
Options expired (in shares)	(180,755)
Options outstanding at the end of the period (in shares)	1,178,045	1,461,469
Options vested and expected to vest at the end of the period (in shares)	1,178,045
Options exercisable at the end of the period (in shares)	892,730
Weighted- Average Exercise Price
Options outstanding at the beginning of the period (in dollars per share)	$ 12.90
Options granted (in dollars per share)	0.00
Options exercised (in dollars per share)	0.00
Options forfeited (in dollars per share)	13.86
Options expired (in dollars per share)	14.01
Options outstanding at the end of the period (in dollars per share)	12.64	$ 12.90
Options vested and expected to vest at the end of the period (in dollars per share)	12.64
Options exercisable at the end of the period (in dollars per share)	$ 13.50
Weighted- Average Remaining Contractual Term (years)
Options outstanding at the end of the period	6 years 1 month 24 days
Options vested and expected to vest at the end of the period	6 years 1 month 24 days
Options exercisable at the end of the period	5 years 9 months 7 days
Aggregate Intrinsic Value (in thousands)
Options outstanding at the end of the period	$ 0
Options vested and expected to vest at the end of the period	0.00
Options exercisable at the end of the period	$ 0