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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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