Benefit Plans (Narrative) (Details) - USD ($)	3 Months Ended	12 Months Ended
	Jun. 30, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2021
Defined Benefit Plan Disclosure [Line Items]
Amounts charged to expense for defined contribution plans			$ 90,000,000	$ 88,000,000	$ 78,000,000
Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation			8,200,000,000	9,100,000,000
Accumulated benefit obligation			176,000,000	393,000,000
Fair value of plan assets			0	149,000,000
Projected benefit obligation			227,000,000	9,324,000,000
Defined benefit plan, pension plan with projected benefit obligation in excess of plan assets, plan assets			0	8,750,000,000
Defined benefit plan, plan assets, amount			$ 8,793,000,000	$ 8,911,000,000	$ 8,167,000,000
Defined benefit plan, assumptions used calculating net periodic benefit cost, expected long-term rate of return on plan assets			6.60%	6.60%	7.80%
Pension [Member] | Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assumptions used calculating net periodic benefit cost, expected long-term rate of return on plan assets		6.10%
Pension [Member] | Emerging Markets [Member]
Defined Benefit Plan Disclosure [Line Items]
Composition of plan assets			1.00%
Pension [Member] | Below grade investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Composition of plan assets			11.00%
Pension [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan assets, target allocation percentage			20.00%			30.00%
Pension [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan assets, target allocation percentage			80.00%			70.00%
Pension [Member] | Fixed Income Securities [Member] | Below grade investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Composition of plan assets			16.00%
Postretirement Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension provisions and postretirement, net	$ 432,000,000
Defined benefit plan, plan assets, amount			$ 185,000,000	$ 201,000,000	$ 213,000,000
Defined benefit plan, assumptions used calculating net periodic benefit cost, expected long-term rate of return on plan assets			7.70%	7.70%	7.80%
Postretirement Benefit Plan [Member] | Emerging Markets [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount			$ 0
Postretirement Benefit Plan [Member] | Below grade investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Composition of plan assets			3.00%
Postretirement Benefit Plan [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan assets, target allocation percentage			55.00%
Postretirement Benefit Plan [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan assets, target allocation percentage			45.00%
Postretirement Benefit Plan [Member] | Fixed Income Securities [Member] | Below grade investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Composition of plan assets			8.00%
Other Postretirement Benefits Plan and Pension Plan [Member] | Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected future employer contributions			$ 30,000,000
Level 3 [Member] | Postretirement Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount			$ 0	$ 0