Consolidated Statements Of Stockholders' Equity (Deficiency) And Comprehensive Income (Loss) - USD ($) $ in Thousands	Total	Common Stock Issued	Additional Paid-In Capital	Treasury Stock	Accumulated Deficit	Accumulated Other Comprehensive Loss
Balance at Jun. 30, 2018	$ (657,742)	$ 779	$ 4,067	$ (195,881)	$ (460,007)	$ (6,700)
Increase (Decrease) in Stockholders' Equity (Deficiency) [Roll Forward]
Net income	145,003				145,003
Other comprehensive income	247					247
Comprehensive income	145,250
Share-based compensation expense	13,658		13,658
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 Mar. 31, 2019	(503,341)	779	5,487	(179,561)	(323,593)	(6,453)
Balance at Dec. 31, 2018	(562,032)	779	1,116	(179,561)	(377,828)	(6,538)
Increase (Decrease) in Stockholders' Equity (Deficiency) [Roll Forward]
Net income	54,235				54,235
Other comprehensive income	85					85
Comprehensive income	54,320
Share-based compensation expense	4,371		4,371
Balance at Mar. 31, 2019	(503,341)	779	5,487	(179,561)	(323,593)	(6,453)
Increase (Decrease) in Stockholders' Equity (Deficiency) [Roll Forward]
Cumulative effect of adoption of ASC 606	372				372
Balance at Jun. 30, 2019	(458,768)	779	9,916	(179,561)	(282,414)	(7,488)
Increase (Decrease) in Stockholders' Equity (Deficiency) [Roll Forward]
Net income	129,301				129,301
Other comprehensive income	287					287
Comprehensive income	129,588
Share-based compensation expense	13,852		13,852
Repurchases of Class A Common Stock	(292,470)			(292,470)
Tax withholding associated with shares issued for share-based compensation	(4,235)		(4,235)
Shares issued upon distribution of Restricted Stock Units	0		(12,130)	15,729	(3,599)
Balance at Mar. 31, 2020	(612,033)	779	7,403	(456,302)	(156,712)	(7,201)
Balance at Dec. 31, 2019	(623,012)	779	3,650	(417,162)	(202,982)	(7,297)
Increase (Decrease) in Stockholders' Equity (Deficiency) [Roll Forward]
Net income	46,270				46,270
Other comprehensive income	96					96
Comprehensive income	46,366
Share-based compensation expense	3,753		3,753
Repurchases of Class A Common Stock	(39,140)			(39,140)
Balance at Mar. 31, 2020	$ (612,033)	$ 779	$ 7,403	$ (456,302)	$ (156,712)	$ (7,201)

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