Debt (Components Of Debt) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Short-term debt	$ 1	$ 1
Unamortized discount	(1)	(1)
Long-Term Debt	1,806	1,950
Total debt	1,807	1,951
Credit Facility [Member]
Debt Instrument [Line Items]
Variable rate (1.50% and 1.64% at September 30, 2014 and December 31, 2013, respectively) Credit Facility, expires December 2018	139	283
Variable interest rate	1.50%	1.64%
Credit facility, maturity date	Dec. 01, 2018
7.35% Senior Notes due 2017 [Member]
Debt Instrument [Line Items]
Stated interest rate	7.35%
Maturity date	2017
7.125% Senior Notes due 2017 [Member]
Debt Instrument [Line Items]
Stated interest rate	7.125%
Maturity date	2017
7.15% Senior Notes due 2018 [Member]
Debt Instrument [Line Items]
Stated interest rate	7.15%
Maturity date	2018
7.5% Senior Notes Due 2018 [Member]
Debt Instrument [Line Items]
Stated interest rate	7.50%
Maturity date	2018
4.10% Senior Notes Due 2022 [Member]
Debt Instrument [Line Items]
Stated interest rate	4.10%
Maturity date	2022
Senior Notes [Member] \| 7.35% Senior Notes due 2017 [Member]
Debt Instrument [Line Items]
Senior Notes	15	15
Senior Notes [Member] \| 7.125% Senior Notes due 2017 [Member]
Debt Instrument [Line Items]
Senior Notes	25	25
Senior Notes [Member] \| 7.15% Senior Notes due 2018 [Member]
Debt Instrument [Line Items]
Short-term debt	1	1
Senior Notes	28	28
Senior Notes [Member] \| 7.5% Senior Notes Due 2018 [Member]
Debt Instrument [Line Items]
Senior Notes	600	600
Senior Notes [Member] \| 4.10% Senior Notes Due 2022 [Member]
Debt Instrument [Line Items]
Senior Notes	$ 1,000	$ 1,000

Date when the debt instrument is scheduled to be fully repaid, in CCYY format.

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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- Details

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- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

+ Details

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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Period Type:	duration

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

+ Details

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- Definition

The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Line-of-Credit Arrangement

-URI http://asc.fasb.org/extlink&oid=6517033

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 45

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=28361426&loc=d3e1314-112600

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 45

-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=28361426&loc=d3e1336-112600

+ Details

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- Definition

Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

+ Details

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- Definition

Carrying value as of the balance sheet date of the portion of long-term notes having the highest claim on the assets of the issuer in case of bankruptcy or liquidation, due within one year or the normal operating cycle, if longer. Senior note holders are paid off in full before any payments are made to debt holders having a lesser priority of repayment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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