Goodwill and Other Intangibles - Changes in the carrying value of goodwill (Details) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
	Jul. 03, 2023	Sep. 30, 2023	Dec. 31, 2023
Goodwill [Line Items]
Goodwill, beginning balance			$ 246
Goodwill, impairment loss		$ (26)
Goodwill, ending balance			305
Verikai, Inc.
Goodwill [Line Items]
Goodwill, impairment loss			(26)
Crop Risk Services
Goodwill [Line Items]
Goodwill acquired during period	$ 85		$ 85