Income Taxes (Reconciliation of Changes to the Valuation Allowance) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Deferred Tax Asset, Valuation Allowance [Roll Forward]
Valuation allowance, beginning balance	$ 1,079	$ 1,539
Establishment of valuation allowance on opening deferred balance	0	0
Return to accrual adjustments	(36)	(16)
State rate and apportionment changes	(66)	(15)
Current period deferred activity	(388)	(1)
Reduction due to 382 limitations on NOLs	0	(428)
Purchase accounting	0	0
Valuation allowance, ending balance	$ 589	$ 1,079