Net Loss Per Share - Basic and Diluted Net Loss Per Share (Parenthetical) (Detail) - shares shares in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of net loss per share	12.0	11.2	9.7
2024 Convertible Notes [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Conversion of shares excluded from computation of diluted EPS	1.4	5.7	7.8
2027 Convertible Notes [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Conversion of shares excluded from computation of diluted EPS	8.1	8.1	8.1