Schedule VI (SUPPLEMENTARY INFORMATION CONCERNING PROPERTY AND CASUALTY OPERATIONS) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters [Abstract]
Deferred Policy Acquisition Costs	$ 3,687	$ 3,346	$ 2,877
Net Reserves for Unpaid Losses	66,270	62,238	58,661
Unearned Premiums	23,504	22,051	19,713
Net Premiums Earned	43,573	40,314	36,850
Net Investment Income	4,927	4,181	3,233
Current Year Claim and Claim Adjustment Expense	26,997	24,956	23,680
Prior Year Claim and Claim Adjustment Expense	(975)	(856)	(1,108)
Amortization of Deferred Policy Acquisition Costs	8,053	7,391	6,480
Net Paid Losses and Loss Expenses	21,503	21,011	19,537
Net Premiums Written	$ 45,142	$ 41,896	$ 38,112