Employee Benefits - Additional Information (Details) - Qualified and Nonqualified - Defined Benefit Pension Plans - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2020	Jan. 01, 2021
Defined Benefit Plan Disclosure [Line Items]
Contributions by employer	$ 2.1
Scenario Forecast
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan expected future employer contributions current fiscal year deferral CARES Act		$ 29.3

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