v3.20.2
Debt - Zero-Coupon Convertible Senior Notes Due in 2020 - Additional Information (Detail) - Zero-Coupon Convertible Senior Notes due in 2020 [Member]
$ in Millions
3 Months Ended
Jun. 30, 2020
USD ($)
shares
Debt Instrument [Line Items]  
Debt converted instrument, aggregate principal amount | $ $ 67
Common Stock [Member]  
Debt Instrument [Line Items]  
Debt instrument, shares issued upon conversion | shares 223,320