Amortized Cost and Estimated Fair Value of Marketable Securities by Contractual Maturity (Detail) - USD ($) $ in Millions |
Mar. 31, 2019 |
Dec. 31, 2018 |
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Cost | ||
Due in one year or less | $ 33 | |
Due after one year through three years | 578 | |
Due after three years through five years | 23 | |
Due after five years | 75 | |
Marketable Securities, Debt Maturities, Amortized Cost, Total | 709 | |
Equity securities | 2 | |
Total Amortized Cost | 711 | $ 813 |
Estimated Fair Value | ||
Due in one year or less | 33 | |
Due after one year through three years | 578 | |
Due after three years through five years | 23 | |
Due after five years | 76 | |
Marketable Securities, Debt Maturities, Fair Value, Total | 710 | |
Equity securities | 2 | |
Total Estimated Fair Value | $ 712 | $ 810 |
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- Definition Marketable Securities, Fair Value [Abstract] No definition available.
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- Definition Marketable Securities, Amortized Cost [Abstract] No definition available.
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- Definition Marketable Securities, Amortized Cost Basis No definition available.
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- Definition Marketable Securities, Debt Maturities, After Five Years, Amortized Cost Basis No definition available.
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- Definition Marketable Securities, Debt Maturities, After Five Years, Fair Value No definition available.
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- Definition Marketable Securities, Debt Maturities, After One Through Three Years, Amortized Cost Basis No definition available.
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- Definition Marketable Securities, Debt Maturities, After One Through Three Years, Fair Value No definition available.
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- Definition Marketable Securities, Debt Maturities, After Three Through Five Years, Amortized Cost Basis No definition available.
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- Definition Marketable Securities, Debt Maturities, After Three Through Five Years, Fair Value No definition available.
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- Definition Marketable Securities, Debt Maturities, Amortized Cost Basis No definition available.
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- Definition Marketable Securities, Debt Maturities, Fair Value No definition available.
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- Definition Marketable Securities, Debt Maturities, Next Twelve Months, Amortized Cost Basis No definition available.
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- Definition Marketable Securities, Debt Maturities, Next Twelve Months, Fair Value No definition available.
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- Definition Marketable Securities, Equity Securities, Amortized Cost Basis No definition available.
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- Definition Marketable Securities, Equity Securities, Fair Value No definition available.
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- Definition Amount of investment in marketable security, classified as current. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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