Reclassifications From Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Reclassifications from accumulated other comprehensive (loss) income
Actuarial losses, net of tax	$ (3)	$ (3)	$ (6)	$ (7)
Interest rate swaps, net of Tax	1	1	1	1
Available-for-sale securities, net of Tax	(1)	0	(1)	0
Selling, general and administrative expenses
Reclassifications from accumulated other comprehensive (loss) income
Actuarial losses, net	3	5	8	10
Tax (benefit)	0	(2)	(2)	(3)
Actuarial losses, net of tax	3	3	6	7
Reclassification out of Accumulated Other Comprehensive Income \| Interest expense
Reclassifications from accumulated other comprehensive (loss) income
Tax (benefit)	0	0	0	0
Interest rate swaps, net of Tax	1	1	1	1
Reclassification out of Accumulated Other Comprehensive Income \| Other, net
Reclassifications from accumulated other comprehensive (loss) income
Available-for-sale securities	(1)	0	(1)	0
Tax expense	0	0	0	0
Available-for-sale securities, net of Tax	(1)	0	(1)	0
Interest Rate Swaps \| Reclassification out of Accumulated Other Comprehensive Income \| Interest expense
Reclassifications from accumulated other comprehensive (loss) income
Interest rate swaps	$ 1	$ 1	$ 1	$ 1

Amount of tax (expense) benefit, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans, attributable to noncontrolling interest.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=68079674&loc=SL4569643-111683

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=64809438&loc=SL4573702-111684

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=68079674&loc=SL4569616-111683

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563

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Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e689-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=64837297&loc=d3e41638-113959

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e637-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6441202&loc=d3e80720-113993

Reference 4: http://www.xbrl.org/2003/role/presentationRef
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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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