Indebtedness Idebtedness (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Senior Notes principle amount	$ 6,000,000,000	$ 6,000,000,000
Redemption percentage of 2015 Senior Notes		100.00%
Redemption percentage for change in control provision on the 2015 Senior Notes		101.00%
Debt issuance costs	47,500,000
Maximum senior unsecured revolving credit facility	$ 1,000,000,000	$ 1,000,000,000
Credit facility term	5 years
Outstanding credit facility borrowings	$ 0	0
2.900% Senior Notes due 2020
Debt Instrument [Line Items]
Senior Notes principle amount	$ 1,500,000,000	$ 1,500,000,000
Senior Notes interest rate	2.90%	2.90%
Percentage par value of Senior Notes	99.792%	99.792%
3.625% Senior Notes due 2022
Debt Instrument [Line Items]
Senior Notes principle amount	$ 1,000,000,000	$ 1,000,000,000
Senior Notes interest rate	3.625%	3.625%
Percentage par value of Senior Notes	99.92%	99.92%
4.050% Senior Notes due 2025
Debt Instrument [Line Items]
Senior Notes principle amount	$ 1,750,000,000	$ 1,750,000,000
Senior Notes interest rate	4.05%	4.05%
Percentage par value of Senior Notes	99.764%	99.764%
5.200% Senior Notes due 2045
Debt Instrument [Line Items]
Senior Notes principle amount	$ 1,750,000,000	$ 1,750,000,000
Senior Notes interest rate	5.20%	5.20%
Percentage par value of Senior Notes	99.294%	99.294%
Investments and other assets \| Designated as hedging instrument
Debt Instrument [Line Items]
Derivative asset, fair value, net	$ 5,600,000	$ 5,600,000	$ 1,900,000
Interest rate swap \| Investments and other assets \| Designated as hedging instrument
Debt Instrument [Line Items]
Derivative asset, fair value, net	$ 5,600,000	$ 5,600,000

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- Definition

Percentage Par Value Of Senior Notes

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- Definition

Face (par) amount of debt instrument at time of issuance.

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value of the amount outstanding under the credit facility.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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