Net Loss Per Share - Additional Information (Detail) shares in Millions	12 Months Ended
Dec. 31, 2020 shares
Convertible Note due 2022 [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Incremental Common Shares Attributable to Dilutive Effect of Contingently Issuable Shares	6.6
Convertible Note due 2024 [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Incremental Common Shares Attributable to Dilutive Effect of Contingently Issuable Shares	13.3

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of contingently issuable shares. Contingently issuable shares are those shares that are issuable for little or no cash contingent on certain conditions being met.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details