Pension and Other Post-retirement Benefits - Level 3 Assets Recognized in AOCL (Detail) - Pension Benefits - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net actuarial losses	$ 40,339	$ 82,796
Prior service cost (credit)	728	1,021
Total (before tax effects)	41,067	$ 83,817
Insurance contracts
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net actuarial losses	(698)
Prior service cost (credit)	310
Total (before tax effects)	$ (388)

Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount, before tax, of accumulated other comprehensive (income) loss for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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