Employee Benefit Plans - Postretirement Healthcare Plan (Details) - Postretirement Healthcare Plan - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits
Defined Benefit Plan, Funded (Unfunded) Status of Plan	$ 0.3	$ 0.4
Minimum age requirement	55 years
Requisite service period	15 years
Net periodic benefit cost	$ 0.5	$ 0.7	$ 0.8

Defined Benefit Plan with Individual, Minimum Age Requirement

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- Definition

Defined Benefit Plan with Individual, Requisite Service Period

+ References

No definition available.

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- Definition

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+ References

No definition available.

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- Definition

Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

+ References

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- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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