Financial Instruments: (Details 3) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2012 basispoint	Dec. 31, 2011
Derivative Financial Instruments
Derivative instruments with credit-risk related contingent features	$ 76	$ 131
Fair Values of Derivative Instruments
Fair value of total derivative instruments, Assets	1,179	1,300
Fair value of total derivative instruments, Liabilities	2,668	2,415
Maximum spread on credit default swap agreements before full overnight collateralization is required (in basis points)	250
Liabilities included in master netting arrangements	230	324
Amount recognized in accounts payable for the obligation to return cash collateral	422	466
Total collateral received, derivatives	483	466
Non-cash collateral received and not recorded on the Statement of Financial Position	61
Derivative instruments designated as hedging instruments
Fair Values of Derivative Instruments
Fair value of total derivative instruments, Assets	996	1,190
Fair value of total derivative instruments, Liabilities	280	428
Derivative instruments not designated as hedging instruments
Fair Values of Derivative Instruments
Fair value of total derivative instruments, Assets	183	110
Fair value of total derivative instruments, Liabilities	39	103
Prepaid expenses and other current assets \| Interest rate contracts \| Derivative instruments designated as hedging instruments
Fair Values of Derivative Instruments
Fair value of total derivative instruments, Assets	56	50
Prepaid expenses and other current assets \| Foreign exchange contracts \| Derivative instruments designated as hedging instruments
Fair Values of Derivative Instruments
Fair value of total derivative instruments, Assets	238	407
Prepaid expenses and other current assets \| Foreign exchange contracts \| Derivative instruments not designated as hedging instruments
Fair Values of Derivative Instruments
Fair value of total derivative instruments, Assets	128	82
Prepaid expenses and other current assets \| Equity contracts \| Derivative instruments not designated as hedging instruments
Fair Values of Derivative Instruments
Fair value of total derivative instruments, Assets	29	7
Investments and sundry assets \| Interest rate contracts \| Derivative instruments designated as hedging instruments
Fair Values of Derivative Instruments
Fair value of total derivative instruments, Assets	700	733
Investments and sundry assets \| Foreign exchange contracts \| Derivative instruments designated as hedging instruments
Fair Values of Derivative Instruments
Fair value of total derivative instruments, Assets	1
Investments and sundry assets \| Foreign exchange contracts \| Derivative instruments not designated as hedging instruments
Fair Values of Derivative Instruments
Fair value of total derivative instruments, Assets	26	21
Long term debt. \| Derivative instruments designated as hedging instruments
Fair Values of Derivative Instruments
Fair value of total derivative instruments, Liabilities	2,350	1,884
Other accrued expenses and liabilities \| Foreign exchange contracts \| Derivative instruments designated as hedging instruments
Fair Values of Derivative Instruments
Fair value of total derivative instruments, Liabilities	194	273
Other accrued expenses and liabilities \| Foreign exchange contracts \| Derivative instruments not designated as hedging instruments
Fair Values of Derivative Instruments
Fair value of total derivative instruments, Liabilities	25	84
Other accrued expenses and liabilities \| Equity contracts \| Derivative instruments not designated as hedging instruments
Fair Values of Derivative Instruments
Fair value of total derivative instruments, Liabilities	4	8
Other liabilities. \| Foreign exchange contracts \| Derivative instruments designated as hedging instruments
Fair Values of Derivative Instruments
Fair value of total derivative instruments, Liabilities	85	155
Other liabilities. \| Foreign exchange contracts \| Derivative instruments not designated as hedging instruments
Fair Values of Derivative Instruments
Fair value of total derivative instruments, Liabilities	$ 11	$ 11

The credit default swap spread which, if exceeded, would trigger contingent features of these agreements.

No definition available.

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- Definition

The amount of non-cash collateral received, primarily U.S. Treasury securities, and is not recorded on the Statement of Financial Position.

+ References

No definition available.

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- Definition

The fair value, as of the date of each statement of financial position presented, of accounts payable which are collateral received for the repayment of the related debt obligation, and that are reclassified and separately reported in the statement of financial position.

+ References

No definition available.

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- Definition

The amount of the obligation to return cash collateral under master netting arrangements that have not been offset against net derivative instrument positions.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6935481&loc=d3e41678-113959

-Subparagraph (b)

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- Definition

Fair value of derivative asset, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (a),(c)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624163-113959

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44C

-Subparagraph a

-Clause 1

-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.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 205G

-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

Fair value of derivative liability, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ References

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- Definition

The amount as of the balance sheet date of the fair value of derivative liabilities that in accordance with the entity's accounting policy was not offset against the right to reclaim cash collateral under a master netting arrangement.

+ References

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

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FIN39-1

-Paragraph 10B

-Subparagraph a

-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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=d3e41678-113959

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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624258-113959

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44D

-Subparagraph b

-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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