Goodwill and Other Intangible Assets - Goodwill (Details)	12 Months Ended
	Dec. 29, 2024 USD ($)	Dec. 31, 2023 USD ($)	Jan. 01, 2023 USD ($)
Goodwill [Line Items]
Goodwill	$ 227,200,000	$ 227,200,000
Accumulated goodwill impairment	$ 528,000,000.0	528,000,000.0	$ 528,000,000.0
Weighted average cost of capital | Fair Value, Inputs, Level 3 [Member]
Goodwill [Line Items]
Goodwill, fair value measurement input	0.110
Long-term growth rate | Fair Value, Inputs, Level 3 [Member] | Minimum
Goodwill [Line Items]
Goodwill, fair value measurement input	0.03
Long-term growth rate | Fair Value, Inputs, Level 3 [Member] | Maximum
Goodwill [Line Items]
Goodwill, fair value measurement input	0.035
HPMC
Goodwill [Line Items]
Goodwill	$ 227,200,000
Impairment of goodwill	0	$ 0	$ 0
Forged Products
Goodwill [Line Items]
Goodwill	$ 161,200,000
Percentage of fair value in excess of carrying value	95.00%
Specialty Materials [Member]
Goodwill [Line Items]
Goodwill	$ 66,000,000.0