Investments - Schedule of Available-For-Sale Investments (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Debt securities
Amortized cost	$ 10,404	$ 4,335
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Fair values	10,404	4,335
U.S. Treasury bills
Debt securities
Amortized cost	0	1,676
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Fair values	0	1,676
Money market mutual funds
Debt securities
Amortized cost	10,266	2,659
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Fair values	10,266	2,659
Other short-term interest-bearing securities
Debt securities
Amortized cost	138	0
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Fair values	$ 138	$ 0

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
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