Financial Instruments - Foreign Currency Risk (Details)	3 Months Ended
Sep. 30, 2020 USD ($) contract $ / $	Sep. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) contract $ / $
Financial Instruments
Unrealized foreign exchange gains (losses)	$ (3,000)	$ (886,000)
Foreign-Exchange Contracts
Financial Instruments
Number of derivative contracts held \| contract	35		13
Notional amounts	$ 12,353,000		$ 3,087,000
Fair Value of Combined Contracts	(3,000)		$ (258,000)
Unrealized foreign exchange gains (losses)	(3,000)	(886,000)
Realized foreign exchange gains (losses)	$ 51,000	$ 17,000
Foreign-Exchange Contracts \| Minimum
Financial Instruments
Exchange/Strike Rates (AUD to USD) \| $ / $	0.61689		0.56516
Foreign-Exchange Contracts \| Maximum
Financial Instruments
Exchange/Strike Rates (AUD to USD) \| $ / $	0.72944		0.68863

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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Nominal or face amount used to calculate payment on derivative.

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The number of derivative instruments of a particular group held by the entity.

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Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

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Amount before tax of foreign currency transaction unrealized gain (loss) recognized in the income statement.

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