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Debt (Details) | 0 Months Ended | 3 Months Ended | 9 Months Ended |  |  |  |  | 0 Months Ended |  |  |  |  | 0 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 30, 2014 EUR (€) | Sep. 30, 2014 Commercial paper [Member] USD ($) | Sep. 30, 2014 Commercial paper [Member] USD ($) | Dec. 31, 2013 Commercial paper [Member] USD ($) | Sep. 30, 2014 3.50% debt securities due September 2015 [Member] Notes Payable, Other Payables [Member] | Aug. 12, 2014 3.50% notes due 2024 [Member] Notes Payable, Other Payables [Member] USD ($) | May 20, 2014 3.50% notes due 2024 [Member] Notes Payable, Other Payables [Member] USD ($) | Jul. 01, 2014 Debt Securities 6.25 Percent, Due 2014 [Member] EUR (€) | Jul. 01, 2014 Debt Securities 6.25 Percent, Due 2014 [Member] Notes Payable, Other Payables [Member] | Jun. 30, 2014 Debt Securities 6.25 Percent, Due 2014 [Member] Notes Payable, Other Payables [Member] EUR (€) | May 20, 2014 4.60% notes due 2044 [Member] Notes Payable, Other Payables [Member] USD ($) | May 07, 2014 2.875% notes due 2026 [Member] Notes Payable, Other Payables [Member] EUR (€) | Jul. 01, 2014 Debt Securities 6.25 Percent, Due 2014 [Member] EUR (€) | Sep. 30, 2014 Short-term debt and current portion of long-term debt [Member] 3.50% debt securities due September 2015 [Member] USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total debt |  | $ 50,000,000 | $ 50,000,000 | $ 0 |  |  |  |  |  |  |  |  |  |
Weighted average commercial paper outstanding |  | 360,000,000 | 338,000,000 |  |  |  |  |  |  |  |  |  |  |
Weighted-average interest rates (as a percent) |  | 0.31% | 0.34% |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount |  |  |  |  |  | 350,000,000 | 250,000,000 |  |  | 500,000,000 | 550,000,000 | 500,000,000 |  | 600,000,000
Debt interest rate percentage |  |  |  |  | 3.50% | 3.50% | 3.50% |  | 6.25% | 6.25% | 4.60% | 2.875% |  |
Repayments of Debt |  |  |  |  |  |  |  | 531,000,000 |  |  |  |  |  |
Payments for Deposits Applied to Debt Retirements | 531,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Repayment of debt |  |  |  |  |  |  |  |  |  |  |  |  | € 500,000,000 |

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