Pension and Other Postretirement Benefits - Schedule of Pension and Postretirement Plans Weighted Average Target and Actual Asset Allocations (Detail)	Dec. 31, 2021	Dec. 31, 2020
Plan Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	100.00%	100.00%
Equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	25.00%	30.00%
Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	65.00%	50.00%
Fixed Income Securities [Member] | Plan Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	64.00%	50.00%
Other Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	10.00%	20.00%
Other Investments [Member] | Plan Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	8.00%	11.00%
Equity Securities [Member] | Plan Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	28.00%	39.00%