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Capital Stock - Summary of Normal Course Issuer Bids (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022
Schedule Of Share Repurchase Programs [Line Items] |  |
Shares purchased | 239,296 | 12,561,487
Cash amount | $ 13 | $ 780
2021 Bid [Member] |  |
Schedule Of Share Repurchase Programs [Line Items] |  |
Shares purchased | 0 | 12,554,879
Cash amount | $ 0 | $ 779
2022 Bid [Member] |  |
Schedule Of Share Repurchase Programs [Line Items] |  |
Shares purchased | 239,296 | 6,608
Cash amount | $ 13 | $ 1

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- Details
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- Details
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