Condensed Consolidated Statements of Shareholders’ Equity (unaudited) - USD ($) $ in Millions	Total	Preferred Stock	Preferred stock additional capital paid-in	Common stock par value	Common stock additional capital paid-in	Retained income	Treasury stock	Accumulated other comprehensive income (loss)	Noncontrolling Interest
Increase (decrease) in equity
Total equity			$ 1,970		$ 3,498	$ 52,767	$ (31,331)	$ 3,304	$ 0
Balance, beginning of period at Dec. 31, 2020			1,970		3,498	52,767	(31,331)	3,304	0
Increase (decrease) in equity
Acquisition			450						(21)
Preferred stock redemption			(250)
Forward contract on accelerated share repurchase agreement					113
Equity incentive plans activity					(15)
Net income (loss)	$ (1,387)					(1,387)			(6)
Dividends on common stock (declared per share of $0.85 and $0.81)						(246)
Dividends on preferred stock						(27)
Shares acquired							(601)
Shares reissued under equity incentive plans, net							46
Change in unrealized net capital gains and losses	(1,500)							(1,500)	0
Change in unrealized foreign currency translation adjustments	34							34
Change in unamortized pension and other postretirement prior service credit	(15)							(15)
Balance, end of period at Mar. 31, 2021	26,792	$ 0	2,170	$ 9	3,596	51,107	(31,886)	1,823	(27)
Increase (decrease) in equity
Total Allstate shareholders’ equity	26,819
Total equity	26,792	0	2,170	9	3,596	51,107	(31,886)	1,823	(27)
Total Allstate shareholders’ equity	25,179
Total equity	25,127		1,970		3,722	53,294	(34,471)	655	(52)
Balance, beginning of period at Dec. 31, 2021	25,127		1,970		3,722	53,294	(34,471)	655	(52)
Increase (decrease) in equity
Acquisition			0						0
Preferred stock redemption			0
Forward contract on accelerated share repurchase agreement					0
Equity incentive plans activity					(16)
Net income (loss)	646					656			(10)
Dividends on common stock (declared per share of $0.85 and $0.81)						(236)
Dividends on preferred stock						(26)
Shares acquired							(794)
Shares reissued under equity incentive plans, net							57
Change in unrealized net capital gains and losses	(1,593)							(1,593)	(12)
Change in unrealized foreign currency translation adjustments	0							0
Change in unamortized pension and other postretirement prior service credit	(15)							(15)
Balance, end of period at Mar. 31, 2022	23,138	0	1,970	9	3,706	53,688	(35,208)	(953)	(74)
Increase (decrease) in equity
Total Allstate shareholders’ equity	23,212
Total equity	$ 23,138	$ 0	$ 1,970	$ 9	$ 3,706	$ 53,688	$ (35,208)	$ (953)	$ (74)