Retirement and Deferred Compensation Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement [Abstract]
Pension contributions	$ 8
Net periodic benefit expense (recovery)	6	$ 6	$ 5
Expected benefit payments in the next fiscal year	10
Defined contribution plans expense	101	90	85
Deferred compensation plans expense	22	12	27
Other Postretirement Benefit Plans [Member]
Statement [Abstract]
Benefit expense	$ 10	$ (4)	$ 7