Retirement Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Contributions to defined contribution plans	$ 37	$ 33	$ 33
Expected benefit plan payments for each of the next five years	53
Expected total benefit plan payments for five years after the next five years	249
Benefit plan payments expected to be funded from cash and cash equivalents and other assets for next fiscal year	15
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 458	671	$ 745
Pension Benefits [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocations	90.00%
Pension Benefits [Member] | Fixed Income Securities [Member] | Level 1 Inputs [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 384	590
Pension Benefits [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocations	10.00%
Fair value of plan assets	$ 49	67
Pension Benefits [Member] | Other Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 25	$ 14
Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan health care cost trend rate assumed for next fiscal year	6.60%
Defined benefit plan ultimate health care cost trend rate	5.00%