Financial Instruments - Summary of Credit Ratings (Detail) |
12 Months Ended |
|---|---|
Dec. 31, 2021 | |
| Moodys [member] | |
| Disclosure of credit risk exposure [Line Items] | |
| Long-term debt | Baa2 |
| Commercial paper | P-2 |
| Trend/Outlook | Positive |
| S&P Global Ratings [Member] | |
| Disclosure of credit risk exposure [Line Items] | |
| Long-term debt | BBB |
| Commercial paper | A-2 |
| Trend/Outlook | Stable |
| DBRS Limited [Member] | |
| Disclosure of credit risk exposure [Line Items] | |
| Long-term debt | BBB (high) |
| Commercial paper | R-2 (high) |
| Trend/Outlook | Stable |
| Fitch [member] | |
| Disclosure of credit risk exposure [Line Items] | |
| Long-term debt | BBB+ |
| Commercial paper | F1 |
| Trend/Outlook | Stable |