Consolidated Statement of Income (Loss) (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Revenues
Premiums	$ 7,616	$ 6,955	$ 15,002	$ 14,184
Net investment income	818	268	1,519	879
Fee income	104	114	205	222
Net realized investment gains (losses)	61	13	105	(85)
Other revenues	88	51	169	109
Total revenues	8,687	7,401	17,000	15,309
Claims and expenses
Claims and claim adjustment expenses	5,045	5,107	10,015	9,896
Amortization of deferred acquisition costs	1,254	1,173	2,461	2,351
General and administrative expenses	1,174	1,121	2,337	2,258
Interest expense	83	85	165	169
Total claims and expenses	7,556	7,486	14,978	14,674
Income (loss) before income taxes	1,131	(85)	2,022	635
Income tax expense (benefit)	197	(45)	355	75
Net income (loss)	$ 934	$ (40)	$ 1,667	$ 560
Net income (loss) per share
Basic (in dollars per share)	$ 3.70	$ (0.16)	$ 6.58	$ 2.19
Diluted (in dollars per share)	$ 3.66	$ (0.16)	$ 6.53	$ 2.19
Weighted average number of common shares outstanding
Basic (in shares)	250.7	251.6	251.4	253.6
Diluted (in shares)	253.1	251.6	253.6	254.7
Cash dividends declared per common share (in dollars per share)	$ 0.88	$ 0.85	$ 1.73	$ 1.67