Net Income (Loss) Per Share - Schedule of Weighted-Average Shares Used for Net Income per Share Footnotes (Detail) - $ / shares	Feb. 01, 2020	Sep. 30, 2019	Jun. 30, 2018	Jun. 30, 2015	Jun. 30, 2014
Earnings Per Share Diluted
Conversion price per share		$ 211.40
Convertible senior notes due 2019 | Common Stock
Earnings Per Share Diluted
Conversion price per share	$ 116.09				$ 116.09
Convertible senior notes due 2020 | Common Stock
Earnings Per Share Diluted
Conversion price per share	118.13			$ 118.13
Convertible senior notes due 2023 | Common Stock
Earnings Per Share Diluted
Conversion price per share	193.65		$ 193.65
Convertible senior notes due 2024 | Common Stock
Earnings Per Share Diluted
Conversion price per share	$ 211.40