Pension and Other Postretirement Benefits - Asset Categories Based on the Nature and Risks of the Plan Assets (Parenthetical) (Detail) - Defined Benefit Pension Plan [Member] - U.S. [Member]	Dec. 31, 2021	Dec. 31, 2020
Alternative Investments, Managed Funds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Target Allocation	89.60%	82.80%
Alternative Investments, Cash and Cash Equivalents [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Target Allocation	10.40%	17.20%