Postretirement Benefits - Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Amounts included in accumulated other comprehensive loss
Net actuarial loss	$ 27,524	$ 118,721
Prior service cost	12,201	9,570
Net amount not yet recognized	$ 39,725	$ 128,291

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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- Definition

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.

+ References

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-Publisher FASB
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- Definition

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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