Retirement Benefits Pension Plan Contributions (Details) - Pension Plan $ in Millions	3 Months Ended
	Mar. 31, 2023 USD ($)
Funded Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 125
Unfunded Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year	400
Defined Benefit Plan, Plan Assets, Contributions by Employer	99
Minimum | Funded Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year	500
Maximum | Funded Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year	$ 600