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Postretirement Benefits - Schedule of Amounts Recognized in Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net amounts recognized at year end	$ (131,239)	$ (208,770)	$ (182,233)	$ (150,071)
Pension plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss (gain)	120,217	200,465
Prior service cost	8,647	4,713
Net amounts recognized at year end	$ 128,864	$ 205,178