Accounts and Financing Receivables - Additional Information (Details) - Rental equipment	3 Months Ended
	Sep. 30, 2017 USD ($)
Accounts Notes And Loans Receivable [Line Items]
Interest rate	5.00%
Term of sales-type lease	3 years
Future minimum lease payments	$ 8,600,000
Future minimum lease payments, 2018	2,900,000
Future minimum lease payments, 2019	2,900,000
Future minimum lease payments, 2020	2,900,000
Residual value of equipment	$ 0