Debt - Summary of Principal Amount, Unamortized Debt Discount and Net Carrying Amount of Liability Component (Detail) - USD ($) |
Dec. 31, 2018 |
Dec. 31, 2017 |
Nov. 30, 2014 |
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| Debt Instrument [Line Items] | |||
| Principal amount | $ 7,400,000,000 | $ 6,650,000,000 | |
| 2019 Cash Convertible Senior Notes [Member] | |||
| Debt Instrument [Line Items] | |||
| Principal amount | 1,150,000,000 | 1,150,000,000 | $ 1,150,000,000 |
| Unamortized debt discount | 45,000,000 | 91,000,000 | |
| Net liability | $ 1,105,000,000 | $ 1,059,000,000 |
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- Definition Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 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. No definition available.
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- Definition Amount, after accumulated amortization, of debt discount. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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