Benefit Plans (Fair Value of Plan Assets) (Details) - USD ($)		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		$ 410,000,000	$ 455,000,000	$ 402,000,000
Foreign Plan [Member] | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		317,000,000	355,000,000
Foreign Plan [Member] | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		84,000,000	90,000,000
Foreign Plan [Member] | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		9,000,000	10,000,000
Foreign Plan [Member] | Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		14,000,000	20,000,000
Foreign Plan [Member] | Mutual funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		14,000,000	20,000,000
Foreign Plan [Member] | Mutual funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Mutual funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Private equity
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		1,000,000	1,000,000
Foreign Plan [Member] | Private equity | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Private equity | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Private equity | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		1,000,000	1,000,000
Foreign Plan [Member] | Government debt securities
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		13,000,000	11,000,000
Foreign Plan [Member] | Government debt securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		13,000,000	11,000,000
Foreign Plan [Member] | Government debt securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Government debt securities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Total plan assets	[1]	371,000,000	413,000,000
Foreign Plan [Member] | Mutual funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		287,000,000	323,000,000
Foreign Plan [Member] | Mutual funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		84,000,000	90,000,000
Foreign Plan [Member] | Mutual funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Real estate
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		2,000,000	2,000,000
Foreign Plan [Member] | Real estate | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Real estate | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Real estate | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		2,000,000	2,000,000
Foreign Plan [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		2,000,000	0
Foreign Plan [Member] | Cash and Cash Equivalents [Member] | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		2,000,000	0
Foreign Plan [Member] | Cash and Cash Equivalents [Member] | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Cash and Cash Equivalents [Member] | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Other assets
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		7,000,000	8,000,000
Foreign Plan [Member] | Other assets | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		1,000,000	1,000,000
Foreign Plan [Member] | Other assets | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Other assets | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		6,000,000	7,000,000
UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		1,026,000,000	1,127,000,000	$ 1,044,000,000
UNITED STATES | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		1,002,000,000	1,091,000,000
UNITED STATES | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		24,000,000	36,000,000
UNITED STATES | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		173,000,000	359,000,000
UNITED STATES | Mutual funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		173,000,000	359,000,000
UNITED STATES | Mutual funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Mutual funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Government debt securities
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		170,000,000	135,000,000
UNITED STATES | Government debt securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		170,000,000	135,000,000
UNITED STATES | Government debt securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Government debt securities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Total plan assets	[2]	653,000,000	593,000,000
UNITED STATES | Mutual funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		653,000,000	593,000,000
UNITED STATES | Mutual funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Mutual funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Real estate
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		24,000,000	36,000,000
UNITED STATES | Real estate | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Real estate | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		24,000,000	36,000,000
UNITED STATES | Real estate | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		6,000,000	4,000,000
UNITED STATES | Cash and Cash Equivalents [Member] | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		6,000,000	4,000,000
UNITED STATES | Cash and Cash Equivalents [Member] | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Cash and Cash Equivalents [Member] | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		$ 0	$ 0

[1] Mutual funds categorized as debt securities consist of mutual funds for which debt securities are the primary underlying investment

[2] Mutual funds categorized as debt securities consist of mutual funds for which debt securities are the primary underlying investment