Statutory Financial Information and Dividend Limitations - Allstates domestic insurance subsidiaries (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Amount per statutory accounting practices
Net income (loss)	$ 7,713	$ 6,246	$ 4,411
Capital and surplus	21,508	21,383
Life and annuity business sold | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Amount per statutory accounting practices
Net income (loss)	1,642	(81)	330
Capital and surplus	0	4,024
Property and casualty
Amount per statutory accounting practices
Net income (loss)	5,975	6,232	3,989
Capital and surplus	21,186	17,128
Accident and health insurance
Amount per statutory accounting practices
Net income (loss)	96	95	$ 92
Capital and surplus	$ 322	$ 231