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Earnings per Share - Additional Information (Detail) $ / shares in Units, $ in Millions | Dec. 31, 2020 USD ($) $ / shares
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Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] |
Stock price | $ / shares | $ 37.12
Senior Unsecured Convertible Bonds [Member] |
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] |
Debt instrument principal amount | $ 750
Expected excess amount over principal upon conversion | $ 605

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