Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance	$ 30	$ 30	$ 30
Additions	0	0	0
Reductions	0	0	0
Balance	30	30	30
Allowance for Price Adjustments [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance	24,075	18,902	19,599
Additions	140,413	115,842	124,694
Reductions	(134,396)	(110,669)	(125,391)
Balance	30,092	24,075	18,902
SEC Schedule, 12-09, Valuation Allowance, Deferred Tax Asset [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance	35,420	30,105	6,178
Additions	2,407	5,315	23,927
Reductions	0	0	0
Balance	$ 37,827	$ 35,420	$ 30,105