Segment Information - Revenues and Intersegment Revenues (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Segment Reporting Information [Line Items]
Total intersegment revenues	$ (829)	$ (753)	$ (1,628)	$ (1,441)
Corporate & Eliminations
Segment Reporting Information [Line Items]
Total intersegment revenues	3	5	6	11
Corporate & Eliminations | ASC
Segment Reporting Information [Line Items]
Total intersegment revenues	3	5	6	11
Corporate & Eliminations | IMS
Segment Reporting Information [Line Items]
Total intersegment revenues	$ 0	$ 0	$ 0	$ 0