Trade Accounts Receivable and Financing Receivables - Additional Information (Details) - USD ($)	3 Months Ended			6 Months Ended		12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Sep. 30, 2018	Sep. 30, 2019
Accounts Notes And Loans Receivable [Line Items]
Accounts receivable	$ 25,669,000			$ 25,669,000			$ 25,144,000
Revenue	9,517,000		$ 11,845,000	$ 18,600,000	$ 22,304,000
Bad debt expenses	$ 8,000,000
Promissory notes receivable maximum interest rate	7.00%			7.00%
Promissory notes receivable maturity month and year				2023-01
Term of sales-type lease	3 years			3 years
Future minimum lease payments	$ 1,400,000			$ 1,400,000
Future minimum lease payments of unearned income	18,000,000,000			18,000,000,000
Interest income earned on lease	23,000		$ 100,000	100,000	$ 100,000
Value of notes with customer	1,704,000			1,704,000			3,472,000
Secured Promissory Note
Accounts Notes And Loans Receivable [Line Items]
Value of notes with customer	$ 10,000,000			$ 10,000,000
Term of the notes	3 years
Interest rate of the notes	7.00%			7.00%
Monthly principal and interest payments	$ 300,000
Frequency of payments	monthly
Product
Accounts Notes And Loans Receivable [Line Items]
Revenue	$ 0
Partially financed product sale	12,500,000
Single Customer
Accounts Notes And Loans Receivable [Line Items]
Accounts receivable	14,000,000			$ 14,000,000
Unrecognized rental revenue and late payment penalties				6,000,000
Revenue		$ 2,500,000
Received cash payment in excess						$ 20,000,000
Single Customer | Trade Accounts Receivable
Accounts Notes And Loans Receivable [Line Items]
Accounts receivable	$ 8,000,000			$ 8,000,000			$ 8,500,000