Fair value measurement (Details) (USD $)
In Millions, unless otherwise specified |
Mar. 31, 2013
|
Dec. 31, 2012
|
---|---|---|
Assets: | ||
Total available-for-sale investments | $ 20,900 | $ 23,745 |
Fair Value, Measurements, Recurring [Member]
|
||
Derivative Assets: | ||
Interest rate swap contracts | 22 | |
Total assets | 21,038 | 23,856 |
Derivative Liabilities: | ||
Contingent consideration obligations in connection with a business combination | 222 | 221 |
Total liabilities | 315 | 286 |
Fair Value, Measurements, Recurring [Member] | Foreign currency contracts [Member]
|
||
Derivative Assets: | ||
Foreign currency contracts | 108 | 46 |
Derivative Liabilities: | ||
Foreign currency contracts | 21 | 59 |
Fair Value, Measurements, Recurring [Member] | Cross currency swap contracts [Member]
|
||
Derivative Assets: | ||
Foreign currency contracts | 8 | 65 |
Derivative Liabilities: | ||
Foreign currency contracts | 72 | 6 |
Fair Value, Measurements, Recurring [Member] | U.S. Treasury securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 2,707 | 4,458 |
Fair Value, Measurements, Recurring [Member] | Other government-related debt securities - U.S. [Member]
|
||
Assets: | ||
Total available-for-sale investments | 1,019 | 1,030 |
Fair Value, Measurements, Recurring [Member] | Other government-related debt securities - Foreign and other [Member]
|
||
Assets: | ||
Total available-for-sale investments | 1,466 | 1,608 |
Fair Value, Measurements, Recurring [Member] | Corporate debt securities - Financial [Member]
|
||
Assets: | ||
Total available-for-sale investments | 3,977 | 3,361 |
Fair Value, Measurements, Recurring [Member] | Corporate debt securities - Industrial [Member]
|
||
Assets: | ||
Total available-for-sale investments | 4,457 | 4,380 |
Fair Value, Measurements, Recurring [Member] | Corporate debt securities - Other [Member]
|
||
Assets: | ||
Total available-for-sale investments | 479 | 452 |
Fair Value, Measurements, Recurring [Member] | Residential mortgage-backed securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 1,817 | 1,829 |
Fair Value, Measurements, Recurring [Member] | Other mortgage- and asset-backed securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 1,497 | 1,767 |
Fair Value, Measurements, Recurring [Member] | Money market mutual funds [Member]
|
||
Assets: | ||
Total available-for-sale investments | 1,742 | 2,620 |
Fair Value, Measurements, Recurring [Member] | Other short-term interest-bearing securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 1,677 | 2,186 |
Fair Value, Measurements, Recurring [Member] | Equity securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 62 | 54 |
Fair Value, Measurements, Recurring [Member] | Quoted prices in active markets for identical assets (Level 1) [Member]
|
||
Derivative Assets: | ||
Interest rate swap contracts | 0 | |
Total assets | 4,511 | 7,132 |
Derivative Liabilities: | ||
Contingent consideration obligations in connection with a business combination | 0 | 0 |
Total liabilities | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Quoted prices in active markets for identical assets (Level 1) [Member] | Foreign currency contracts [Member]
|
||
Derivative Assets: | ||
Foreign currency contracts | 0 | 0 |
Derivative Liabilities: | ||
Foreign currency contracts | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Quoted prices in active markets for identical assets (Level 1) [Member] | Cross currency swap contracts [Member]
|
||
Derivative Assets: | ||
Foreign currency contracts | 0 | 0 |
Derivative Liabilities: | ||
Foreign currency contracts | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Quoted prices in active markets for identical assets (Level 1) [Member] | U.S. Treasury securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 2,707 | 4,458 |
Fair Value, Measurements, Recurring [Member] | Quoted prices in active markets for identical assets (Level 1) [Member] | Other government-related debt securities - U.S. [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Quoted prices in active markets for identical assets (Level 1) [Member] | Other government-related debt securities - Foreign and other [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Quoted prices in active markets for identical assets (Level 1) [Member] | Corporate debt securities - Financial [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Quoted prices in active markets for identical assets (Level 1) [Member] | Corporate debt securities - Industrial [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Quoted prices in active markets for identical assets (Level 1) [Member] | Corporate debt securities - Other [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Quoted prices in active markets for identical assets (Level 1) [Member] | Residential mortgage-backed securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Quoted prices in active markets for identical assets (Level 1) [Member] | Other mortgage- and asset-backed securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Quoted prices in active markets for identical assets (Level 1) [Member] | Money market mutual funds [Member]
|
||
Assets: | ||
Total available-for-sale investments | 1,742 | 2,620 |
Fair Value, Measurements, Recurring [Member] | Quoted prices in active markets for identical assets (Level 1) [Member] | Other short-term interest-bearing securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Quoted prices in active markets for identical assets (Level 1) [Member] | Equity securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 62 | 54 |
Fair Value, Measurements, Recurring [Member] | Significant other observable inputs (Level 2) [Member]
|
||
Derivative Assets: | ||
Interest rate swap contracts | 22 | |
Total assets | 16,527 | 16,724 |
Derivative Liabilities: | ||
Contingent consideration obligations in connection with a business combination | 0 | 0 |
Total liabilities | 93 | 65 |
Fair Value, Measurements, Recurring [Member] | Significant other observable inputs (Level 2) [Member] | Foreign currency contracts [Member]
|
||
Derivative Assets: | ||
Foreign currency contracts | 108 | 46 |
Derivative Liabilities: | ||
Foreign currency contracts | 21 | 59 |
Fair Value, Measurements, Recurring [Member] | Significant other observable inputs (Level 2) [Member] | Cross currency swap contracts [Member]
|
||
Derivative Assets: | ||
Foreign currency contracts | 8 | 65 |
Derivative Liabilities: | ||
Foreign currency contracts | 72 | 6 |
Fair Value, Measurements, Recurring [Member] | Significant other observable inputs (Level 2) [Member] | U.S. Treasury securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Significant other observable inputs (Level 2) [Member] | Other government-related debt securities - U.S. [Member]
|
||
Assets: | ||
Total available-for-sale investments | 1,019 | 1,030 |
Fair Value, Measurements, Recurring [Member] | Significant other observable inputs (Level 2) [Member] | Other government-related debt securities - Foreign and other [Member]
|
||
Assets: | ||
Total available-for-sale investments | 1,466 | 1,608 |
Fair Value, Measurements, Recurring [Member] | Significant other observable inputs (Level 2) [Member] | Corporate debt securities - Financial [Member]
|
||
Assets: | ||
Total available-for-sale investments | 3,977 | 3,361 |
Fair Value, Measurements, Recurring [Member] | Significant other observable inputs (Level 2) [Member] | Corporate debt securities - Industrial [Member]
|
||
Assets: | ||
Total available-for-sale investments | 4,457 | 4,380 |
Fair Value, Measurements, Recurring [Member] | Significant other observable inputs (Level 2) [Member] | Corporate debt securities - Other [Member]
|
||
Assets: | ||
Total available-for-sale investments | 479 | 452 |
Fair Value, Measurements, Recurring [Member] | Significant other observable inputs (Level 2) [Member] | Residential mortgage-backed securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 1,817 | 1,829 |
Fair Value, Measurements, Recurring [Member] | Significant other observable inputs (Level 2) [Member] | Other mortgage- and asset-backed securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 1,497 | 1,767 |
Fair Value, Measurements, Recurring [Member] | Significant other observable inputs (Level 2) [Member] | Money market mutual funds [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Significant other observable inputs (Level 2) [Member] | Other short-term interest-bearing securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 1,677 | 2,186 |
Fair Value, Measurements, Recurring [Member] | Significant other observable inputs (Level 2) [Member] | Equity securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Significant unobservable inputs (Level 3) [Member]
|
||
Derivative Assets: | ||
Interest rate swap contracts | 0 | |
Total assets | 0 | 0 |
Derivative Liabilities: | ||
Contingent consideration obligations in connection with a business combination | 222 | 221 |
Total liabilities | 222 | 221 |
Fair Value, Measurements, Recurring [Member] | Significant unobservable inputs (Level 3) [Member] | Foreign currency contracts [Member]
|
||
Derivative Assets: | ||
Foreign currency contracts | 0 | 0 |
Derivative Liabilities: | ||
Foreign currency contracts | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Significant unobservable inputs (Level 3) [Member] | Cross currency swap contracts [Member]
|
||
Derivative Assets: | ||
Foreign currency contracts | 0 | 0 |
Derivative Liabilities: | ||
Foreign currency contracts | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Significant unobservable inputs (Level 3) [Member] | U.S. Treasury securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Significant unobservable inputs (Level 3) [Member] | Other government-related debt securities - U.S. [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Significant unobservable inputs (Level 3) [Member] | Other government-related debt securities - Foreign and other [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Significant unobservable inputs (Level 3) [Member] | Corporate debt securities - Financial [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Significant unobservable inputs (Level 3) [Member] | Corporate debt securities - Industrial [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Significant unobservable inputs (Level 3) [Member] | Corporate debt securities - Other [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Significant unobservable inputs (Level 3) [Member] | Residential mortgage-backed securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Significant unobservable inputs (Level 3) [Member] | Other mortgage- and asset-backed securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Significant unobservable inputs (Level 3) [Member] | Money market mutual funds [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Significant unobservable inputs (Level 3) [Member] | Other short-term interest-bearing securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Significant unobservable inputs (Level 3) [Member] | Equity securities [Member]
|
||
Assets: | ||
Total available-for-sale investments | $ 0 | $ 0 |