Investments in Debt and Equity Securities (Details 2) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Available-for-sale Securities, Continuous Unrealized Loss Position
Less than 12 months - Fair Value	$ 1,895	$ 359
Less than 12 months - Unrealized losses	52	5
12 months or more - Fair Value	87	55
12 months or more - Unrealized losses	8	1
Total - Fair Value	1,982	414
Total - Unrealized losses	60	6
Other U.S. and non-U.S. government bonds
Available-for-sale Securities, Continuous Unrealized Loss Position
Less than 12 months - Fair Value	24
Less than 12 months - Unrealized losses	1
12 months or more - Fair Value	0
12 months or more - Unrealized losses	0
Total - Fair Value	24
Total - Unrealized losses	1
Corporate bonds
Available-for-sale Securities, Continuous Unrealized Loss Position
Less than 12 months - Fair Value	1,433	270
Less than 12 months - Unrealized losses	37	4
12 months or more - Fair Value	61	33
12 months or more - Unrealized losses	6	1
Total - Fair Value	1,494	303
Total - Unrealized losses	43	5
Asset-backed securities
Available-for-sale Securities, Continuous Unrealized Loss Position
Less than 12 months - Fair Value	109
Less than 12 months - Unrealized losses	3
12 months or more - Fair Value	0
12 months or more - Unrealized losses	0
Total - Fair Value	109
Total - Unrealized losses	3
U.S. governmental agency mortgage-backed securities
Available-for-sale Securities, Continuous Unrealized Loss Position
Less than 12 months - Fair Value	231	89
Less than 12 months - Unrealized losses	8	1
12 months or more - Fair Value	25	22
12 months or more - Unrealized losses	2	0
Total - Fair Value	256	111
Total - Unrealized losses	10	$ 1
Commercial
Available-for-sale Securities, Continuous Unrealized Loss Position
Less than 12 months - Fair Value	98
Less than 12 months - Unrealized losses	3
12 months or more - Fair Value	1
12 months or more - Unrealized losses	0
Total - Fair Value	99
Total - Unrealized losses	$ 3