v3.8.0.1

Debt and Other Commitments - Debt Narrative (Details) - Convertible Debt [Member] $ / shares in Units, $ in Millions | 1 Months Ended |  |  |
--- | --- | --- | --- | ---
Jun. 29, 2014 USD ($) day $ / shares | Dec. 31, 2017 USD ($) | Jan. 01, 2017 USD ($) | Dec. 31, 2011 USD ($)
Debt Instrument [Line Items] |  |  |  |
Carrying value of equity component, net of issuance costs |  | $ 161 | $ 161 |
2019 Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Principal amount | $ 633 | 633 | 633 |
Interest rate on convertible senior notes | 0.00% |  |  |
Conversion rate | 0.0039318 |  |  |
Threshold note trading days | day | 5 |  |  |
Threshold consecutive note trading days | day | 10 |  |  |
Threshold percentage of note price trigger | 98.00% |  |  |
Threshold common stock trading days | day | 20 |  |  |
Threshold consecutive common stock trading days | day | 30 |  |  |
Threshold percentage of common stock price trigger | 130.00% |  |  |
Effective interest rate used to measure fair value of convertible senior note | 2.90% |  |  |
2021 Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Principal amount | $ 517 | $ 517 | $ 517 |
Interest rate on convertible senior notes | 0.50% |  |  |
Conversion rate | 0.0039318 |  |  |
Threshold note trading days | day | 5 |  |  |
Threshold consecutive note trading days | day | 10 |  |  |
Threshold percentage of note price trigger | 98.00% |  |  |
Threshold common stock trading days | day | 20 |  |  |
Threshold consecutive common stock trading days | day | 30 |  |  |
Threshold percentage of common stock price trigger | 130.00% |  |  |
Effective interest rate used to measure fair value of convertible senior note | 3.50% |  |  |
2019 and 2021 Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Principal amount | $ 1,150 |  |  |
Debt issuance price as a percentage of par | 100.00% |  |  |
Net proceeds from issuance, after deducting offering expenses payable | $ 1,132 |  |  |
Conversion price (in dollars per share) | $ / shares | $ 254.34 |  |  |
Repurchase price, percent of principal | 100.00% |  |  |
Fair value of liability component, upon issuance | $ 972 |  |  |
Carrying value of equity component, net of issuance costs | 161 |  |  |
Cash proceeds | $ 1,133 |  |  |
2016 Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Principal amount |  |  |  | $ 920
Interest rate on convertible senior notes |  |  |  | 0.25%
Effective interest rate used to measure fair value of convertible senior note |  |  |  | 4.50%

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- Definition Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16(a)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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