Employee Benefit Plans and Other Postretirement Benefits - Additional Information (Details) - USD ($)	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Pension Plans \| Qualified Plan
Pension Contributions [Abstract]
Contributions to pension plan	$ 0	$ 3,900,000

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Name:	us-gaap_DefinedBenefitPlanContributionsByEmployer
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration