Accumulated Other Comprehensive Income - Tax Effect Allocated to Each Component of Other Comprehensive Income(loss) (Detail) ¥ in Millions, $ in Millions	6 Months Ended
Jun. 30, 2020 CNY (¥)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 CNY (¥)
Other Comprehensive Income (Loss), Tax [Abstract]
Other comprehensive (loss)/income before reclassification	¥ (40)	$ (6)	¥ (171)
Amounts reclassified from accumulated other comprehensive income	63	9	127
Net current-period other comprehensive (loss) income	¥ 23	$ 3	¥ (44)

OtherComprehensiveIncomeNetUnrealizedGainsAndLossesOnSecuritiesTax

No definition available.

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- Definition

Amount, before adjustment, of tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

+ References

+ Details

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- Definition

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e640-108580

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27357-111563

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- References

No definition available.

+ Details

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