10-Q Medical Claims Payable (Reconciliation Of The Beginning And Ending Balances For Medical Claims Payable) (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended		12 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Medical Claims Payable [Line Items]
Gross medical claims payable, beginning of period			$ 15,348			$ 13,282	$ 15,348	$ 13,282	$ 13,282	$ 11,135	$ 8,647
Ceded medical claims payable, beginning of period			(6)			(21)	(6)	(21)	(21)	(46)	(33)
Net medical claims payable, beginning of period			15,342			13,261	15,342	13,261	13,261	11,089	8,614
Business combinations and purchase adjustments							0	133
Current period net incurred medical claims							91,058	84,177	113,414	100,440	85,094
Prior periods redundancies							(1,342)	(901)	(869)	(1,703)	(637)
Total net incurred medical claims	$ 29,538	$ 30,495	$ 29,683	$ 28,511	$ 27,634	$ 27,131	89,716	83,276	112,545	98,737	84,457
Net payments attributable to current period medical claims							77,048	70,453	98,997	88,156	74,629
Net payments attributable to prior periods medical claims							12,097	11,219	11,600	8,829	7,692
Total net payments							89,145	81,672	110,597	96,985	82,321
Net medical claims payable, end of period	15,913			14,998			15,913	14,998	15,342	13,261	11,089
Ceded medical claims payable, end of period	4			3			4	3	6	21	46
Gross medical claims payable, end of period	$ 15,917			$ 15,001			$ 15,917	$ 15,001	$ 15,348	$ 13,282	$ 11,135