Condensed Consolidated Statements of Operations (unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Revenues
Net investment income	$ 690	$ 764	$ 1,846	$ 2,446
Net gains (losses) on investments and derivatives	(167)	105	(1,167)	818
Total revenues	13,208	12,480	37,765	37,577
Costs and expenses
Property and casualty insurance claims and claims expense	10,073	8,264	27,262	21,514
Shelter-in-Place Payback expense	0	0	0	29
Accident, health and other policy benefits	263	277	801	771
Amortization of deferred policy acquisition costs	1,682	1,582	4,913	4,650
Operating costs and expenses	1,842	1,890	5,594	5,304
Pension and other postretirement remeasurement (gains) losses	79	40	91	(404)
Restructuring and related charges	14	23	27	145
Amortization of purchased intangibles	90	109	264	267
Interest expense	85	69	251	246
Total costs and expenses	14,128	12,254	39,203	32,522
(Loss) income from operations before income tax expense	(920)	226	(1,438)	5,055
Income tax (benefit) expense	(237)	20	(377)	1,008
Net (loss) income from continuing operations	(683)	206	(1,061)	4,047
Income (loss) from discontinued operations, net of tax	0	325	0	(3,272)
Net (loss) income	(683)	531	(1,061)	775
Less: Net loss attributable to noncontrolling interest	(15)	(7)	(34)	(7)
Net (loss) income attributable to Allstate	(668)	538	(1,027)	782
Less: Preferred stock dividends	26	30	79	87
Net (loss) income applicable to common shareholders	$ (694)	$ 508	$ (1,106)	$ 695
Basic
Continuing operations (in dollars per share)	$ (2.58)	$ 0.62	$ (4.04)	$ 13.31
Discontinued operations (in dollars per share)	0	1.11	0	(10.98)
Earnings per common share applicable to common shareholders - Basic (in dollars per share)	(2.58)	1.73	(4.04)	2.33
Diluted
Continuing operations (in dollars per share)	(2.58)	0.62	(4.04)	13.11
Discontinued operations (in dollars per share)	0	1.09	0	(10.81)
Earnings per common share applicable to common shareholders - Diluted (in dollars per share)	$ (2.58)	$ 1.71	$ (4.04)	$ 2.30
Weighted average common shares - Basic (in shares)	268.7	293.1	273.5	298.1
Weighted average common shares - Diluted (in shares)	268.7	297.9	273.5	302.6
Property and casualty insurance premiums
Revenues
Property and casualty insurance premiums	$ 11,661	$ 10,615	$ 34,004	$ 31,366
Accident and health insurance premiums and contract charges
Revenues
Insurance premiums, commissions and fees	463	460	1,398	1,362
Other revenue
Revenues
Insurance premiums, commissions and fees	$ 561	$ 536	$ 1,684	$ 1,585