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Pension Plans and Postretirement Benefits - Plans' Level 3 Instruments Reconciliation (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($)
Fair Value, Separate Account Investment [Line Items]
Balance at beginning of period	$ 1,333,309
Balance at end of period	1,310,311
Level 3
Fair Value, Separate Account Investment [Line Items]
Balance at beginning of period	0
Purchases	45,645
Unrealized gain	652
Foreign currency exchange rate changes	520
Balance at end of period	$ 46,817

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- Definition

Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Translation

+ References

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- Definition

Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from actual return (loss) on assets still held.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Amount, measured using unobservable input, of increase (decrease) in plan asset of defined benefit plan from purchase, sale and settlement of trade associated with underlying investment.

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