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Stock-based compensation - Effects on cash flows (Details) (USD $)
In Millions, unless otherwise specified |
12 Months Ended | ||
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Dec. 31, 2014
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Dec. 31, 2013
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Dec. 31, 2012
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| Disclosure of Compensation Related Costs, Share-based Payments [Abstract] | |||
| Proceeds from common stock transactions | $ 616us-gaap_ProceedsFromIssuanceOrSaleOfEquity | $ 1,314us-gaap_ProceedsFromIssuanceOrSaleOfEquity | $ 523us-gaap_ProceedsFromIssuanceOrSaleOfEquity |
| Tax benefit realized from stock options exercised | $ 218us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation | $ 227us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation | $ 133us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation |
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- Definition
Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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