Insurance (Rollforward of Unpaid Claims) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Liability for Claims and Claims Adjustment Expense [Line Items]
Balance at January 1,	$ 20,013	$ 18,591	$ 19,216
Less: Reinsurance recoverables	3,121	2,417	2,377
Net Balance at January 1,	16,892	16,174	16,839
Incurred related to:
Current year	27,285	28,270	27,272
Prior years	766	934	192
Total incurred	28,051	29,204	27,464
Paid related to:
Current year	(20,051)	(21,111)	(20,230)
Prior years	(7,395)	(7,256)	(6,241)
Total paid	(27,446)	(28,367)	(26,471)
Liability for Unpaid Claims and Claims Adjustment Expense, Adjustments	15,083
Net Balance at December 31,	17,497	16,892	16,174
Add: Reinsurance recoverables	2,916	3,121	2,417
Balance at December 31,	20,413	20,013	18,591
Disposal Group, Held-for-sale, Not Discontinued Operations
Paid related to:
Liability for Unpaid Claims and Claims Adjustment Expense, Adjustments	0	(55)	(1,658)
Disposal Group, Disposed of by Sale, Not Discontinued Operations
Paid related to:
Liability for Unpaid Claims and Claims Adjustment Expense, Adjustments	$ 0	$ (64)	$ 0