Segment Information - Disaggregation of Revenue by Major End Market Served (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Revenue, Major Customer [Line Items]
Sales	$ 2,313	$ 1,942
Engine Products
Revenue, Major Customer [Line Items]
Sales	1,253	974
Fastening Systems
Revenue, Major Customer [Line Items]
Sales	471	412
Engineered Structures
Revenue, Major Customer [Line Items]
Sales	294	304
Forged Wheels
Revenue, Major Customer [Line Items]
Sales	295	252
Aerospace - Commercial
Revenue, Major Customer [Line Items]
Sales	1,215	1,016
Aerospace - Commercial | Engine Products
Revenue, Major Customer [Line Items]
Sales	702	535
Aerospace - Commercial | Fastening Systems
Revenue, Major Customer [Line Items]
Sales	322	275
Aerospace - Commercial | Engineered Structures
Revenue, Major Customer [Line Items]
Sales	191	206
Aerospace - Commercial | Forged Wheels
Revenue, Major Customer [Line Items]
Sales	0	0
Aerospace - Defense
Revenue, Major Customer [Line Items]
Sales	366	333
Aerospace - Defense | Engine Products
Revenue, Major Customer [Line Items]
Sales	238	211
Aerospace - Defense | Fastening Systems
Revenue, Major Customer [Line Items]
Sales	51	42
Aerospace - Defense | Engineered Structures
Revenue, Major Customer [Line Items]
Sales	77	80
Aerospace - Defense | Forged Wheels
Revenue, Major Customer [Line Items]
Sales	0	0
Commercial Transportation
Revenue, Major Customer [Line Items]
Sales	346	305
Commercial Transportation | Engine Products
Revenue, Major Customer [Line Items]
Sales	0	0
Commercial Transportation | Fastening Systems
Revenue, Major Customer [Line Items]
Sales	51	53
Commercial Transportation | Engineered Structures
Revenue, Major Customer [Line Items]
Sales	0	0
Commercial Transportation | Forged Wheels
Revenue, Major Customer [Line Items]
Sales	295	252
Gas Turbines
Revenue, Major Customer [Line Items]
Sales	284	204
Gas Turbines | Engine Products
Revenue, Major Customer [Line Items]
Sales	284	204
Gas Turbines | Fastening Systems
Revenue, Major Customer [Line Items]
Sales	0	0
Gas Turbines | Engineered Structures
Revenue, Major Customer [Line Items]
Sales	0	0
Gas Turbines | Forged Wheels
Revenue, Major Customer [Line Items]
Sales	0	0
Other
Revenue, Major Customer [Line Items]
Sales	102	84
Other | Engine Products
Revenue, Major Customer [Line Items]
Sales	29	24
Other | Fastening Systems
Revenue, Major Customer [Line Items]
Sales	47	42
Other | Engineered Structures
Revenue, Major Customer [Line Items]
Sales	26	18
Other | Forged Wheels
Revenue, Major Customer [Line Items]
Sales	$ 0	$ 0