Defined Benefit Plans - Defined Benefit Plans Narrative (Details) - Pension Plans, Defined Benefit [Member] $ in Millions	3 Months Ended
	Mar. 31, 2021 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 1.5
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year	$ 3.6