Basis of Presentation and Summary of Significant Accounting Policies (Narrative, Goodwill and Other Intangible Assets) (Details) $ in Millions	3 Months Ended			12 Months Ended
	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)	Sep. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) segment	Jun. 30, 2022 USD ($)	Mar. 31, 2023
Goodwill and Intangible Assets [Line Items]
Number of Operating Segments | segment				2
Goodwill, Impairment Loss				$ 1,231	$ 2,084
Medical Unit
Goodwill and Intangible Assets [Line Items]
Discount Rate, fair value inputs	10.00%	10.50%	10.50%	10.00%		10.00%
Goodwill, Impairment Loss	$ 368	$ 709	$ 154	$ 1,200	$ 2,100
Minimum
Goodwill and Intangible Assets [Line Items]
Discount Rate, fair value inputs	9.50%			9.50%
Maximum
Goodwill and Intangible Assets [Line Items]
Discount Rate, fair value inputs	11.00%			11.00%