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Share-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	12 Months Ended
	Sep. 30, 2014	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018	Dec. 05, 2012
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, description		Options and RSUs granted to the Company’s non-employee directors vest in full upon completion of one year of service on the Board following the date of the grant
Options granted, Number of shares		0	0	0
Total unrecognized share-based compensation cost related to stock options		$ 0.0
Stock options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Service period of share-based compensation vested, years		4 years
Stock options [Member] \| Share-based compensation granted after December 5, 2012 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expire from date of grant, years		8 years
Stock options [Member] \| Share-based compensation granted prior to December 5, 2012 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expire from date of grant, years		10 years
Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Service period of share-based compensation vested, years	4 years
RSUs granted, Weighted average grant date fair value		$ 27.96	$ 46.62	$ 32.67
Fair value of restricted stock units, vested		$ 32.4	$ 27.6	$ 20.4
Total unrecognized share-based compensation cost related to RSUs		$ 38.2
Total unrecognized share-based compensation cost, weighted-average period, years		2 years 1 month 6 days
Unrecognized share-based compensation cost		$ 38.2
Restricted Stock Units (RSUs) [Member] \| Non Employee Director [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Service period of share-based compensation vested, years		1 year
The 2017 Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares approved		2,200,000
2003 Plan [Member] \| Stock options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future grant		100,000
The 2010 Plan [Member] \| Options and Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future grant		4,500,000
2012 Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares approved					2,000,000.0
Shares issued under the Plan		1,700,000
Unrecognized share-based compensation cost		$ 0.7