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Marketable Securities - Changes in Value of Marketable Securities Reported in Current Assets on Consolidated Balance Sheets (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Marketable Securities [Line Items] |  |  |
Beginning Balance | $ 330 | $ 431 |
Purchase |  |  | $ 99
Proceeds at maturity | (200) | (100) |
Change in fair value included in OCI | 3 | (1) |
Ending Balance | 133 | 330 | 431
U.S. Treasury Debt Securities [Member] |  |  |
Marketable Securities [Line Items] |  |  |
Beginning Balance | 330 | 431 |
Proceeds at maturity | (200) | (100) |
Change in fair value included in OCI | 3 | (1) |
Ending Balance | $ 133 | $ 330 | $ 431

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- Definition Other comprehensive income loss marketable securities adjustment before tax. + References No definition available. + Details
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- Definition Amount of investment in marketable security, classified as current. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=118951113&loc=d3e6676-107765 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&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 Amount of cash outflow for purchase of marketable security. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26853-111562 + Details
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- Definition The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period. + References No definition available. + Details
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