Retirement Plans and Profit Sharing Arrangements (Benefit Obligation and Fair Value) (Details 2) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Pension Plans [Member]
Change in benefit obligation
Benefit obligation at beginning of year	$ 967	$ 995
Service cost	44	48	$ 47
Interest cost	36	30	28
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Other Change	(15)
Benefits paid	(9)	(9)
Actuarial (gain) loss	131	(59)
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment	(7)
Settlements	(42)	(29)
Foreign currency rate changes	6	(9)
Benefit obligation at end of year	1,111	967	995
Change in fair value of plan assets
Fair value of plan assets at the beginning of the year	728	748
Actual return on plan assets	130	(59)
Employer contributions	24	86
Benefits paid	(9)	(9)
Settlements	(42)	(29)
Foreign currency rate changes	7	(9)
Fair value of plan assets at the end of the year	838	728	748
Other Postretirement Benefits Plan [Member]
Change in benefit obligation
Benefit obligation at beginning of year	14	15
Interest cost	0	1
Benefits paid	(1)	(1)
Actuarial (gain) loss	1	(1)
Benefit obligation at end of year	$ 14	$ 14	$ 15