Amortized Cost and Estimated Fair Value of Marketable Securities by Contractual Maturity (Detail) - USD ($) $ in Millions |
Jun. 30, 2018 |
Dec. 31, 2017 |
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Cost | ||
Due in one year or less | $ 193 | |
Due after one year through three years | 434 | |
Due after three years through five years | 24 | |
Due after five years | 73 | |
Marketable Securities, Debt Maturities, Amortized Cost, Total | 724 | |
Equity securities | 2 | |
Total Amortized Cost | 726 | $ 736 |
Estimated Fair Value | ||
Due in one year or less | 193 | |
Due after one year through three years | 430 | |
Due after three years through five years | 23 | |
Due after five years | 72 | |
Marketable Securities, Debt Maturities, Fair Value, Total | 718 | |
Equity securities | 2 | |
Total Estimated Fair Value | $ 720 | $ 749 |
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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 investments in debt and equity securities, including, but not limited to, held-to-maturity, trading and available-for-sale expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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