Investments - Additional Information (Detail) - USD ($) $ in Millions |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Investments Debt And Equity Securities [Abstract] | ||
| Available for sale investments | $ 0 | $ 0 |
| Held-to-maturity investments | 249 | $ 188 |
| Foreign government debt, after five years through ten years | 80 | |
| Held-to-maturity investments, after ten years | $ 169 |
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of investment in debt security measured at amortized cost (held-to-maturity). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing after tenth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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