Segment Information - Disaggregation of Revenue by Major End Market Served (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenue, Major Customer [Line Items]
Sales	$ 1,835	$ 1,658	$ 5,539	$ 4,909
Third-party sales
Revenue, Major Customer [Line Items]
Sales	1,835	1,658	5,539	4,909
Third-party sales | Engine Products
Revenue, Major Customer [Line Items]
Sales	945	798	2,763	2,414
Third-party sales | Fastening Systems
Revenue, Major Customer [Line Items]
Sales	392	348	1,175	989
Third-party sales | Engineered Structures
Revenue, Major Customer [Line Items]
Sales	253	227	790	634
Third-party sales | Forged Wheels
Revenue, Major Customer [Line Items]
Sales	245	285	811	872
Third-party sales | Aerospace - Commercial
Revenue, Major Customer [Line Items]
Sales	962	820	2,869	2,345
Third-party sales | Aerospace - Commercial | Engine Products
Revenue, Major Customer [Line Items]
Sales	534	446	1,554	1,324
Third-party sales | Aerospace - Commercial | Fastening Systems
Revenue, Major Customer [Line Items]
Sales	245	209	740	563
Third-party sales | Aerospace - Commercial | Engineered Structures
Revenue, Major Customer [Line Items]
Sales	183	165	575	458
Third-party sales | Aerospace - Commercial | Forged Wheels
Revenue, Major Customer [Line Items]
Sales	0	0	0	0
Third-party sales | Aerospace - Defense
Revenue, Major Customer [Line Items]
Sales	289	251	859	764
Third-party sales | Aerospace - Defense | Engine Products
Revenue, Major Customer [Line Items]
Sales	189	165	566	502
Third-party sales | Aerospace - Defense | Fastening Systems
Revenue, Major Customer [Line Items]
Sales	43	41	119	131
Third-party sales | Aerospace - Defense | Engineered Structures
Revenue, Major Customer [Line Items]
Sales	57	45	174	131
Third-party sales | Aerospace - Defense | Forged Wheels
Revenue, Major Customer [Line Items]
Sales	0	0	0	0
Third-party sales | Commercial Transportation
Revenue, Major Customer [Line Items]
Sales	310	352	1,010	1,064
Third-party sales | Commercial Transportation | Engine Products
Revenue, Major Customer [Line Items]
Sales	0	0	0	0
Third-party sales | Commercial Transportation | Fastening Systems
Revenue, Major Customer [Line Items]
Sales	65	67	199	192
Third-party sales | Commercial Transportation | Engineered Structures
Revenue, Major Customer [Line Items]
Sales	0	0	0	0
Third-party sales | Commercial Transportation | Forged Wheels
Revenue, Major Customer [Line Items]
Sales	245	285	811	872
Third-party sales | Industrial and Other
Revenue, Major Customer [Line Items]
Sales	274	235	801	736
Third-party sales | Industrial and Other | Engine Products
Revenue, Major Customer [Line Items]
Sales	222	187	643	588
Third-party sales | Industrial and Other | Fastening Systems
Revenue, Major Customer [Line Items]
Sales	39	31	117	103
Third-party sales | Industrial and Other | Engineered Structures
Revenue, Major Customer [Line Items]
Sales	13	17	41	45
Third-party sales | Industrial and Other | Forged Wheels
Revenue, Major Customer [Line Items]
Sales	$ 0	$ 0	$ 0	$ 0