Retirement Plans and Profit Sharing Arrangements (Assets Measured at Fair Value) (Details 6) - Pension Plans [Member] - USD ($) $ in Millions		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 628	$ 608	$ 612
Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		241	214
Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		344	357
Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0	0
U.S. large cap stocks [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		149	157
U.S. large cap stocks [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		73	74
U.S. large cap stocks [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		76	83
U.S. small cap stocks [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		73	58
U.S. small cap stocks [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		69	55
U.S. small cap stocks [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		4	3
Non-U.S. large cap stocks [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		56	55
Non-U.S. large cap stocks [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		22	21
Non-U.S. large cap stocks [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		34	34
Non-U.S. small cap stocks [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		21	21
Non-U.S. small cap stocks [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		21	21
Emerging markets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		37	35
Emerging markets [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		14	14
Emerging markets [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		23	21
U.S. investment grade bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		36	33
U.S. investment grade bonds [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		26	19
U.S. investment grade bonds [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		10	14
U.S. high yield bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		24	26
U.S. high yield bonds [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		24	26
Non-U.S. investment grade bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		14	14
Non-U.S. investment grade bonds [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		14	14
Real estate investment trusts [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	[1]	17	16
Hedge funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	[1]	26	21
Pooled pension funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		142	143
Pooled pension funds [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		142	143
AVC assets (pooled pension funds) [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		17	19
AVC assets (pooled pension funds) [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		17	19
Cash equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		16	10
Cash equivalents [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 16	$ 10

[1] Amounts are comprised of certain investments that are measured at fair value using the NAV per share (or its equivalent) as a practical expedient and have not been classified in the fair value hierarchy. See Note 2 for further information.