Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
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	18,902	19,599	16,700
Additions	115,842	124,694	113,970
Reductions	(110,669)	(125,391)	(111,071)
Balance	24,075	18,902	19,599
SEC Schedule, 12-09, Valuation Allowance, Deferred Tax Asset [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance	30,105	6,178	2,894
Additions	5,315	23,927	3,284
Reductions	0	0	0
Balance	$ 35,420	$ 30,105	$ 6,178