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DEBT AND OTHER FINANCING ARRANGEMENTS - Revolving Credit Facility and Term Loan (Details) - USD ($)				3 Months Ended	6 Months Ended		9 Months Ended	12 Months Ended
	Oct. 31, 2019	Oct. 09, 2019	Nov. 09, 2017	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Apr. 30, 2021	Sep. 30, 2019
Debt Instrument [Line Items]
Extension fee								$ 200,000
Repayments of debt				$ 20,000,000
Debt premium					$ 732,000	$ 45,000
Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity								$ 10,000,000
Jpmorgan Chase Bank N.a
Debt Instrument [Line Items]
Repayment of line of credit, net	$ 10,100,000
Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Variable rate	4.00%
Revolving Credit Facility \| Jpmorgan Chase Bank N.a \| Credit Agreement
Debt Instrument [Line Items]
Debt instrument, term			5 years
Proceeds from revolving credit facility			$ 35,000,000.0
Maximum borrowing capacity			12,500,000
Revolving Credit Facility \| Heritage Bank Of Commerce \| Loan And Security Agreement
Debt Instrument [Line Items]
Repayment of line of credit, net			7,200,000
Term Loan
Debt Instrument [Line Items]
Debt issuance costs		$ 900,000
Commitment fee		100,000
Debt premium		2,100,000
Term Loan \| Jpmorgan Chase Bank N.a \| Credit Agreement
Debt Instrument [Line Items]
Proceeds from revolving credit facility			25,000,000
Cantaloupe
Debt Instrument [Line Items]
Proceeds from revolving credit facility			$ 27,800,000
Commitment Letter \| Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity		30,000,000
First draw	$ 15,000,000
Commitment Termination Fee, Percent	3.00%
Interest rate	9.75%
Commitment fee		$ 1,200,000
Forecast \| Subsequent Event \| Commitment Letter \| Term Loan
Debt Instrument [Line Items]
Second draw							$ 15,000,000
Prior to December 31, 2020 \| Term Loan
Debt Instrument [Line Items]
Prepayment premium					5.00%
Between January 1, 2021 and December 31, 2021 \| Term Loan
Debt Instrument [Line Items]
Prepayment premium					3.00%
Between January 1, 2022 and December 31, 2022 \| Term Loan
Debt Instrument [Line Items]
Prepayment premium					1.00%
After January 1, 2023 \| Term Loan
Debt Instrument [Line Items]
Prepayment premium					0.00%
Minimum \| Term Loan
Debt Instrument [Line Items]
Annual mandatory prepayment of excess cash flow					0.00%
Maximum \| Term Loan
Debt Instrument [Line Items]
Annual mandatory prepayment of excess cash flow					75.00%