Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Millions	Total	Common Stock [Member]	Additional paid-in capital [Member]	Accumulated other comprehensive loss [Member]	Retained earnings (accumulated deficit) [Member]	Non-Controlling Interest [Member]
Beginning Balance at Jun. 30, 2018	$ 966.1	$ 0.7	$ 915.4	$ (4.1)	$ 54.1
Issuance of common stock under share-based compensation plans	1.9		1.9
Issuance of common stock for acquisition	127.4		127.4
Share-based payment expense	7.7		7.7
Net income (loss)	(0.7)				(0.7)
Other comprehensive income (loss), net of tax	(0.2)			(0.2)
Ending Balance at Sep. 30, 2018	1,102.2	0.7	1,052.4	(4.3)	53.4
Beginning Balance at Jun. 30, 2018	966.1	0.7	915.4	(4.1)	54.1
Net income (loss)	8.8
Ending Balance at Mar. 31, 2019	1,081.8	0.7	1,057.0	(5.7)	29.8
Beginning Balance at Sep. 30, 2018	1,102.2	0.7	1,052.4	(4.3)	53.4
Issuance of common stock under share-based compensation plans	2.6		2.6
Share-based payment expense	7.5		7.5
Repurchase and retirement of common stock	(50.0)		(16.9)		(33.1)
Net income (loss)	2.6				2.6
Other comprehensive income (loss), net of tax	(0.7)			(0.7)
Ending Balance at Dec. 31, 2018	1,064.2	0.7	1,045.6	(5.0)	22.9
Issuance of common stock under share-based compensation plans	1.9		1.9
Share-based payment expense	9.5		9.5
Net income (loss)	6.9				6.9
Other comprehensive income (loss), net of tax	(0.7)			(0.7)
Ending Balance at Mar. 31, 2019	1,081.8	0.7	1,057.0	(5.7)	29.8
Beginning Balance at Jun. 30, 2019	1,088.9	0.7	1,068.0	(5.4)	25.6
Issuance of common stock under share-based compensation plans	(0.5)		(0.5)
Share-based payment expense	8.8		8.8
Net income (loss)	(20.6)				(20.6)
Other comprehensive income (loss), net of tax	(2.1)			(2.1)
Ending Balance at Sep. 30, 2019	1,074.5	0.7	1,076.3	(7.5)	5.0
Beginning Balance at Jun. 30, 2019	1,088.9	0.7	1,068.0	(5.4)	25.6
Net income (loss)	(144.1)
Ending Balance at Mar. 31, 2020	967.2	0.7	1,092.8	(7.8)	(118.5)
Beginning Balance at Sep. 30, 2019	1,074.5	0.7	1,076.3	(7.5)	5.0
Issuance of common stock under share-based compensation plans	1.8		1.8
Share-based payment expense	7.0		7.0
Non-controlling interest	0.1					$ 0.1
Net income (loss)	(8.3)				(8.3)
Other comprehensive income (loss), net of tax	2.2			2.2
Ending Balance at Dec. 31, 2019	1,077.3	0.7	1,085.1	(5.3)	(3.3)	0.1
Issuance of common stock under share-based compensation plans	0.2		0.2
Share-based payment expense	7.5		7.5
Non-controlling interest	(0.1)					$ (0.1)
Net income (loss)	(115.2)				(115.2)
Reclassification out of accumulated other comprehensive loss upon the deconsolidation of a subsidiary	0.1			0.1
Other comprehensive income (loss), net of tax	(2.6)			(2.6)
Ending Balance at Mar. 31, 2020	$ 967.2	$ 0.7	$ 1,092.8	$ (7.8)	$ (118.5)