Marketable and Other Securities - Fair Value of Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Marketable Securities [Line Items]
Total available-for-sale debt securities with contractual maturities	$ 16,133
Total cash and cash equivalents	20,067	$ 19,992
Cash and cash equivalents	466	269
Total restricted cash	3,475	3,125
Due in one year or less	12,003
Due between one and five years	4,130
Total available-for-sale debt securities with contractual maturities	16,133
Cruise
Marketable Securities [Line Items]
Total cash and cash equivalents	1,600	761
Cash and cash equivalents
Marketable Securities [Line Items]
Cash and time deposits	7,881	8,010
Total available-for-sale debt securities with contractual maturities	8,148	6,897
Total available-for-sale debt securities with contractual maturities	8,148	6,897
Cash and cash equivalents \| Level 2 \| U.S. government and agencies
Marketable Securities [Line Items]
Total available-for-sale debt securities with contractual maturities	722	1,370
Total available-for-sale debt securities with contractual maturities	722	1,370
Cash and cash equivalents \| Level 2 \| Corporate debt
Marketable Securities [Line Items]
Total available-for-sale debt securities with contractual maturities	5,321	3,476
Total available-for-sale debt securities with contractual maturities	5,321	3,476
Cash and cash equivalents \| Level 2 \| Sovereign debt
Marketable Securities [Line Items]
Total available-for-sale debt securities with contractual maturities	2,105	2,051
Total available-for-sale debt securities with contractual maturities	2,105	2,051
Cash and cash equivalents \| Level 1
Marketable Securities [Line Items]
Money market funds	4,038	5,085
Marketable debt securities
Marketable Securities [Line Items]
Total available-for-sale debt securities with contractual maturities	8,609	9,046
Total available-for-sale debt securities with contractual maturities	8,609	9,046
Marketable debt securities \| Cruise
Marketable Securities [Line Items]
Total available-for-sale debt securities with contractual maturities	1,500	943
Total available-for-sale debt securities with contractual maturities	1,500	943
Marketable debt securities \| Level 2 \| U.S. government and agencies
Marketable Securities [Line Items]
Total available-for-sale debt securities with contractual maturities	2,071	1,771
Total available-for-sale debt securities with contractual maturities	2,071	1,771
Marketable debt securities \| Level 2 \| Corporate debt
Marketable Securities [Line Items]
Total available-for-sale debt securities with contractual maturities	3,396	3,630
Total available-for-sale debt securities with contractual maturities	3,396	3,630
Marketable debt securities \| Level 2 \| Sovereign debt
Marketable Securities [Line Items]
Total available-for-sale debt securities with contractual maturities	2,567	3,013
Total available-for-sale debt securities with contractual maturities	2,567	3,013
Marketable debt securities \| Level 2 \| Mortgage and asset-backed
Marketable Securities [Line Items]
Total available-for-sale debt securities with contractual maturities	575	632
Total available-for-sale debt securities with contractual maturities	575	632
Restricted cash - cash equivalents \| Level 1
Marketable Securities [Line Items]
Money market funds	$ 3,009	$ 2,856

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