Goodwill and Other Intangible Assets - Schedule of Goodwill and Other Intangible Asset Balances (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Goodwill
Goodwill, Beginning Balance			$ 239
Additions			5
Impairment	$ (164)	$ 0	(164)	$ 0
Goodwill, Ending Balance	80		80
Intangible Assets
Beginning balance, cost			231
Beginning balance, accumulated amortization			(37)
Beginning balance, net carrying amount			194
Additions			5
Amortization			(9)
Ending balance, cost	236		236
Ending balance, accumulated amortization	(46)		(46)
Ending balance, net carrying amount	190		190
Total Goodwill and Other Intangible Assets - Net
Beginning balance			433
Additions			10
Amortization			(9)
Impairment	(164)	$ 0	(164)	$ 0
Ending balance	$ 270		$ 270

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