Schedule VI (Details) - Consolidated Property and Casualty Insurance Entity [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Supplementary Information Concerning Property-Casualty Insurance Operations
Deferred acquisition costs	$ 2,358	$ 2,273	$ 2,120
Claims and claim adjustment expense reserves	54,510	51,836	50,653
Discount from reserves for unpaid claims	1,138	1,155	1,158
Unearned premiums	15,222	14,604	13,555
Earned premiums	29,044	28,272	27,059
Net investment income	2,227	2,468	2,474
Claims and claim adjustment expenses incurred related to current year	19,285	18,854	18,614
Claims and claim adjustment expenses incurred related to prior year	(267)	164	(406)
Amortization of deferred acquisition costs	4,773	4,601	4,381
Paid claims and claim adjustment expenses	16,589	17,794	17,060
Net written premiums	$ 29,732	$ 29,151	$ 27,708