Consolidated Statements of Stockholders' Equity (Deficiency) - USD ($) $ in Thousands	Total	Common Stock Issued [Member]	Additional Paid-In Capital [Member]	Treasury Stock [Member]	Retained Earnings (Accumulated Deficit) [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance at Jun. 30, 2017	$ (944,207)	$ 779	$ 6,909	$ (198,800)	$ (746,539)	$ (6,556)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	288,862				288,862
Other comprehensive income	1,247					1,247
Comprehensive income	290,109
Share-based compensation expense	13,979		13,979
Tax withholding associated with shares issued for share-based compensation	(3,773)		(3,773)
Shares issued upon distribution of Restricted Stock Units	0		(13,048)	16,769	(3,721)
Repurchases of Class A common stock	(13,850)			(13,850)
Reclassification of Stranded Tax Effects	0				1,391	(1,391)
Balance at Jun. 30, 2018	(657,742)	779	4,067	(195,881)	(460,007)	(6,700)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	186,182				186,182
Other comprehensive income	(788)					(788)
Comprehensive income	185,394
Share-based compensation expense	18,087		18,087
Tax withholding associated with shares issued for share-based compensation	(4,879)		(4,879)
Shares issued upon distribution of Restricted Stock Units	0		(7,359)	16,320	(8,961)
Balance at Jun. 30, 2019	(458,768)	779	9,916	(179,561)	(282,414)	(7,488)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of adoption of ASC 606	372				372
Net income	185,221				185,221
Other comprehensive income	(716)					(716)
Comprehensive income	184,505
Share-based compensation expense	19,235		19,235
Tax withholding associated with shares issued for share-based compensation	(4,290)		(4,290)
Shares issued upon distribution of Restricted Stock Units	0		(12,130)	15,729	(3,599)
Repurchases of Class A common stock	(293,531)			(293,531)
Balance at Jun. 30, 2020	$ (552,849)	$ 779	$ 12,731	$ (457,363)	$ (100,792)	$ (8,204)