Investments in Debt and Equity Securities (Details 2) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Available-for-sale Securities, Continuous Unrealized Loss Position
Less than 12 months - Fair Value	$ 215	$ 13
Less than 12 months - Unrealized losses	2	0
12 months or more - Fair Value	6	4
12 months or more - Unrealized losses	0	0
Total - Fair Value	221	17
Total - Unrealized losses	2	0
Corporate bonds
Available-for-sale Securities, Continuous Unrealized Loss Position
Less than 12 months - Fair Value	215	13
Less than 12 months - Unrealized losses	2	0
12 months or more - Fair Value	6	4
12 months or more - Unrealized losses	0	0
Total - Fair Value	221	17
Total - Unrealized losses	$ 2	$ 0

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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), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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