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- Definition

Proceeds from Sale of Equity Securities, FV-NI

+ References

No definition available.

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- Definition

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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- Definition

Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

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Amount of 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).

+ References

No definition available.

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

+ References

No definition available.

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Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of investment in equity security without readily determinable fair value.

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Amount of impairment loss on investment in equity security without readily determinable fair value.

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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.

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INVESTMENTS - Narrative (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
INVESTMENTS - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	May 31, 2020	Dec. 31, 2019	Dec. 31, 2017	Dec. 31, 2016
Schedule of Investments [Line Items]
Proceeds from sale of available-for-sale debt securities					$ 2,200
Net gains (losses) on marketable equity securities	$ 730			$ (49)	1,258	$ 419
Impairment of investment	0			0	100	0
Trip.com Group
Schedule of Investments [Line Items]
Proceeds from sale of securities					525
Net gains (losses) on marketable equity securities				(165)	(201)	48
Trip.com Group \| Trip.com Group convertible debt securities
Schedule of Investments [Line Items]
Amortized cost of available-for-sale debt securities	525				525
Trip.com Group 1% Note Due 2020 \| Trip.com Group convertible debt securities
Schedule of Investments [Line Items]
Amortized cost of available-for-sale debt securities							$ 250
Meituan
Schedule of Investments [Line Items]
Fair value of equity securities	2,500				2,500			$ 1,100
Net gains (losses) on marketable equity securities	727			$ 116	1,400	$ 371
Payments to acquire investments									$ 450
Long-term Investments \| Investment in private company equity securities
Schedule of Investments [Line Items]
Cost of investment	501				501			501
Investment in equity securities without readily determinable FV	404				404			501
Long-term Investments \| Redeemable Convertible Preferred Stock
Schedule of Investments [Line Items]
Amortized cost of available-for-sale debt securities	250				250			250
Estimated fair value	250				250			250
Long-term Investments \| Trip.com Group
Schedule of Investments [Line Items]
Cost of investment in equity securities								655
Fair value of equity securities								726
Long-term Investments \| Trip.com Group \| Trip.com Group convertible debt securities
Schedule of Investments [Line Items]
Amortized cost of available-for-sale debt securities	525				525			775
Estimated fair value	493				493			767
Long-term Investments \| Trip.com Group 1.25% Notes due 2022 \| Trip.com Group convertible debt securities
Schedule of Investments [Line Items]
Amortized cost of available-for-sale debt securities										$ 25
Long-term Investments \| Didi Chuxing \| Investment in private company equity securities
Schedule of Investments [Line Items]
Cost of investment	500				500			500
Impairment of investment			$ 100
Investment in equity securities without readily determinable FV	400		400		400
Long-term Investments \| Grab \| Redeemable Convertible Preferred Stock
Schedule of Investments [Line Items]
Estimated fair value	$ 200				$ 200			$ 200
Unrealized gain (loss) on debt securities		$ 20	$ (20)