Retirement Plans and Profit Sharing Arrangements (Net Periodic Pension Cost) (Details 1) - Pension Plans [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined benefit plans:
Service cost	$ 47	$ 44	$ 46
Interest cost	28	29	27
Expected return on plan assets	(45)	(41)	(40)
Amortization of prior service costs	(1)	(1)	(1)
Amortization of net loss	10	6	9
Other	3	4	4
Net periodic benefit cost	$ 42	$ 41	$ 45