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Financial Instruments and Risk Management - Fair Value Information on Other Financial Assets and Liabilities Recorded at Amortized Cost (Detail) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash equivalents | $ 3,006 | $ 2,597
Short-term, deposits | 581 | 4
Estimate Fair Value [Member] | Senior Unsecured Convertible Bonds Issued on July 3, 2017 Tranche A [Member] |  |
Long-term debt |  |
Senior unsecured convertible bonds |  | 1,030
Estimate Fair Value [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash equivalents | 2,637 | 1,691
Short-term, deposits | 581 | 4
Estimate Fair Value [Member] | Fair Value, Inputs, Level 1 [Member] | Senior Unsecured Convertible Bonds Issued on July 3, 2017 Tranche B [Member] |  |
Long-term debt |  |
Senior unsecured convertible bonds | 1,359 | 1,073
Estimate Fair Value [Member] | Fair Value, Inputs, Level 1 [Member] | Senior Unsecured Convertible Bonds Issued on August 4, 2020 [Member] |  |
Long-term debt |  |
Senior unsecured convertible bonds | 1,835 | 0
Estimate Fair Value [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Long-term debt |  |
Bank loans (including current portion) | 583 | 718
Estimate Fair Value [Member] | Fair Value, Inputs, Level 3 [Member] | Senior Unsecured Convertible Bonds Issued on July 3, 2017 Tranche A [Member] |  |
Long-term debt |  |
Senior unsecured convertible bonds |  | 1,030
Carrying Amount [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash equivalents | 2,637 | 1,691
Short-term, deposits | 581 | 4
Carrying Amount [Member] | Fair Value, Inputs, Level 1 [Member] | Senior Unsecured Convertible Bonds Issued on July 3, 2017 Tranche B [Member] |  |
Long-term debt |  |
Senior unsecured convertible bonds | 674 | 654
Carrying Amount [Member] | Fair Value, Inputs, Level 1 [Member] | Senior Unsecured Convertible Bonds Issued on August 4, 2020 [Member] |  |
Long-term debt |  |
Senior unsecured convertible bonds | 1,364 | 0
Carrying Amount [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Long-term debt |  |
Bank loans (including current portion) | $ 583 | 718
Carrying Amount [Member] | Fair Value, Inputs, Level 3 [Member] | Senior Unsecured Convertible Bonds Issued on July 3, 2017 Tranche A [Member] |  |
Long-term debt |  |
Senior unsecured convertible bonds |  | $ 700

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- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3044-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121566466&loc=d3e6676-107765 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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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. + References No definition available. + Details
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- Definition Including the current and noncurrent portions, carrying value as of the balance sheet date of loans from a bank with maturities initially due after one year or beyond the normal operating cycle if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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=120400017&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -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=120398452&loc=d3e534808-122878 + Details
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- Definition Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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=120398452&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 + Details
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