Decrease for amounts repaid on the debt instrument for the period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(f))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph f

-Article 4

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- Definition

Interest rate stated in the contractual debt agreement.

+ References

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- Definition

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

+ 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

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The net realized foreign currency transaction gain (loss) (pretax) included in determining net income from transactions that were settled as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 830

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6450189&loc=d3e30690-110894

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

-Publisher FASB

-Name Accounting Standards Codification

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 830

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 52

-Paragraph 30

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Amount of gain (loss) from the difference between the repurchase price of a debt instrument initially issued by the entity and the net carrying amount of the debt at the time of its repurchase.

+ References

No definition available.

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Net Interest and Other Financial Costs - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended		0 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Mar. 27, 2013 2014 Senior Convertible Notes	Jun. 30, 2013 2014 Senior Convertible Notes	Jun. 30, 2012 Senior Notes Due Twenty Thirteen [Member]	Jun. 30, 2012 Senior Notes Due Twenty Thirteen [Member]
Interest Expense [Line Items]
Net foreign currency remeasurement losses	$ 3	$ 10	$ 12	$ 8
Charge associated with repurchases/redemptions of senior notes						34	18	18
Repurchased face amount of senior notes					$ 542	$ 542	$ 300	$ 300
Senior notes stated interest rate						4.00%
Debt instrument, due date						May 15, 2014		Jun. 01, 2013