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Segmented Information - Schedule of Reconciliation for Adjusted EBIT to Consolidated Income Before Income Taxes (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Segment Reporting [Abstract] |  |
Net income | $ 1,632 | $ 2,332
Add (deduct): |  |
Interest expense, net | 82 | 93
Other expense, net | 240 | 63
Income taxes | 591 | 619
Adjusted EBIT | $ 2,545 | $ 3,107

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