INCOME TAXES - Narrative (Details) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2018
Operating Loss Carryforwards [Line Items]
Loss carryforwards		$ 60,834,000
Deferred tax assets, valuation allowance, released		5,818,000
Transition tax liability	$ 946,000	0	$ (679,000)	$ 946,000
Tax Act, provisional liability					$ 343,000
Tax Act, transition tax for accumulated foreign earnings, other long term liabilities		233,000
Unrecognized tax benefits		0	0
Accrual for interest and penalties related to uncertain tax positions		0	$ 0
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Loss carryforwards		53,411,000
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Loss carryforwards		7,423,000
Germany
Operating Loss Carryforwards [Line Items]
Deferred tax assets, valuation allowance, released		$ (537,000)