BUSINESS BUSINESS - Additional Information (Details) - USD ($)		3 Months Ended												6 Months Ended		9 Months Ended		12 Months Ended			36 Months Ended
	Oct. 09, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Mar. 31, 2018	Mar. 31, 2017	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2019
Subsequent Event [Line Items]
Cash and cash equivalents		$ 27,464,000				$ 83,964,000	$ 17,055,000	$ 15,360,000	$ 51,870,000	$ 12,745,000	$ 17,780,000	$ 18,034,000	$ 18,198,000	$ 15,360,000	$ 18,034,000	$ 17,055,000	$ 17,780,000	$ 27,464,000	$ 83,964,000	$ 12,745,000	$ 27,464,000
Working capital surplus		2,800,000																2,800,000			2,800,000
Accrued sales tax		16,559,000				12,686,000												16,559,000	12,686,000		16,559,000
Net loss		10,541,000	$ 4,510,000	$ 10,657,000	$ 6,320,000	$ 1,696,000	$ 3,223,000	$ 4,194,000	$ 2,171,000	$ 2,938,000	$ 925,000	$ 232,000	$ 3,370,000	$ 6,365,000	$ 3,602,000	$ 9,588,000	$ 4,527,000	32,028,000	$ 11,284,000	$ 7,465,000	50,800,000
Private Placement | Subsequent Event
Subsequent Event [Line Items]
Shares sold (in shares)	3,800,000
Price per share (in USD per share)	$ 5.25
Gross proceeds from offering	$ 19,950,000
Cash placement fee	1,200,000
Commitment Letter | Forecast | Letter of Credit | Subsequent Event
Subsequent Event [Line Items]
Maximum borrowing capacity	30,000,000
First draw	15,000,000
Second draw	$ 15,000,000
Annual interest	9.75%
Commitment fee	$ 1,200,000
Cash placement fee	$ 750,000
JPMorgan Chase Bank N.a
Subsequent Event [Line Items]
Revolving credit facility and term loan outstanding		$ 11,500,000																$ 11,500,000			$ 11,500,000