Balance sheet information - Intangibles, Other Assets and Accrued Expenses (Details) - USD ($)	3 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Jun. 30, 2019
Balance Sheet Related Disclosures [Abstract]
Goodwill	$ 14,300,000		$ 26,100,000
Goodwill, reduction	11,800,000
Acquired developed technology	13,875,000		13,875,000
Less accumulated amortization	(12,712,000)		(12,494,000)
Intangible assets, net	1,163,000		1,381,000
Amortization of intangible assets	218,000	$ 284,000
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity
2020	654,000
2021	509,000
Other Assets
Deposits and other assets	919,000		956,000
Non-marketable equity investments	458,000		458,000
Non-marketable equity investment greater than 5% in LLC	15,600,000		0
Non-marketable debt investment	2,000,000		0
Total other assets	18,977,000		1,414,000
Accrued Expenses
Accrued compensation and benefits	7,051,000		13,288,000
Accrued royalties	14,672,000		21,604,000
Customer overpayments and related reserves	4,674,000		4,291,000
Other accrued expenses	11,968,000		9,716,000
Total accrued expenses	$ 38,365,000		$ 48,899,000