Income Taxes - Narrative (Details) - USD ($)	3 Months Ended					12 Months Ended			59 Months Ended
	Mar. 31, 2020	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2020	Jul. 31, 2017	Jul. 01, 2017	Jun. 30, 2017
Tax Credit Carryforward [Line Items]
Decrease in deferred tax assets					$ 6,600,000
Increase in prepaid tax asset					$ 6,600,000
De-recognition of prepaid tax asset											$ 5,500,000
Deferred tax asset, certain China patent rights and certain manufacturing related IP										$ 12,900,000
Book value, certain China patent rights and certain manufacturing related IP										$ 0
Valuation allowance						$ 37,827,000	$ 35,420,000		$ 37,827,000
Valuation allowance increase						2,400,000	5,300,000
Undistributed earnings of foreign subsidiaries						159,400,000			159,400,000
Unrecognized tax benefits		$ 7,143,000				7,126,000	7,150,000	$ 7,143,000	7,126,000			$ 6,589,000
Unrecognized tax benefit, amount netted against deferred tax assets						6,300,000			6,300,000
Unrecognized tax benefits that would reduce effective income tax rate						4,300,000			4,300,000
Decrease in unrecognized tax benefits is reasonably possible						100,000			100,000
Income tax interest and penalties accrued						100,000	200,000		100,000
Income tax interest and penalties expense						$ 30,000.00	$ 30,000.00
Tax Cuts and Jobs Act, change in tax rate, income tax benefit		2,500,000	$ 2,700,000
Tax Cuts and Jobs Act, measurement period adjustment, income tax expense (benefit)	$ (1,100,000)	$ 200,000
United States statutory rate				34.00%		21.00%	21.00%	28.10%
Income tax benefit						$ 348,000	$ 1,256,000	$ 708,000
Long-term Income Tax Payable [Member]
Tax Credit Carryforward [Line Items]
Unrecognized tax benefits						800,000			800,000
Federal [Member]
Tax Credit Carryforward [Line Items]
Net operating loss carryforwards						18,000,000.0			18,000,000.0
Research and development tax credit carryforwards						8,300,000			8,300,000
State [Member]
Tax Credit Carryforward [Line Items]
Tax credit carryforward						7,100,000			7,100,000
Tax credit carryforward, subject to expiration						600,000			600,000
Tax credit carryforward, not subject to expiration						6,500,000			6,500,000
Net operating loss carryforwards						800,000			800,000
Corporate Joint Venture
Tax Credit Carryforward [Line Items]
Net operating loss carryforwards						108,000,000.0			108,000,000.0
State research and development credit carryforward
Tax Credit Carryforward [Line Items]
Valuation allowance						5,400,000	5,100,000		5,400,000
Net operating loss, fixed asset and intangible asset | Corporate Joint Venture
Tax Credit Carryforward [Line Items]
Valuation allowance						$ 32,400,000	$ 30,300,000		32,400,000
Altera Corp. v. Commissioner
Tax Credit Carryforward [Line Items]
Income tax benefit									$ 0