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Summary of Significant Accounting Policies (Details) $ in Thousands		12 Months Ended
	Sep. 26, 2023 shares	Dec. 27, 2025 USD ($) renewal_option shares	Dec. 28, 2024 USD ($) shares	Dec. 30, 2023 USD ($)	Sep. 25, 2023 shares
Noncontrolling Interest [Line Items]
Common stock, authorized (in shares) \| shares	250,000,000	250,000,000	250,000,000		100,000,000
Stock split ratio, common stock	2	2
Performance obligation payment term		60 days
Temporary investments		$ 1,030,000	$ 776,600
Gain on short term investments		18,547	914	$ 41,865
Marketable securities, realized gain		16,700	400	17,100
Marketable securities, unrealized gain		1,900	500	24,800
Allowance for credit losses		$ 2,545	3,724
Number of operating lease renewal options \| renewal_option		1
Operating lease renewal term		5 years
Specified percentage over which unrecognized gains and losses are amortized		10.00%
Average remaining service period for the pension plans		11 years
Environmental Remediation Expense, Statement of Income or Comprehensive Income [Extensible Enumeration]		Environmental Remediation Expense, Non-Operating Properties
Stock-based awards excluded from the computation of diluted earnings per share (in shares) \| shares		157,000
Foreign currency transactions (losses) gains		$ (2,600)	$ 7,300	$ (4,400)
Tecumseh Products Holdings LLC
Noncontrolling Interest [Line Items]
Equity method investment, ownership percentage		50.00%
Retail Distribution Business
Noncontrolling Interest [Line Items]
Equity method investment, ownership percentage		28.00%
Minimum
Noncontrolling Interest [Line Items]
Operating lease, lease term		1 year
Intangible assets, useful life		3 years
Maximum
Noncontrolling Interest [Line Items]
Operating lease, lease term		15 years
Intangible assets, useful life		20 years
Buildings \| Minimum
Noncontrolling Interest [Line Items]
Property, plant and equipment, useful life		20 years
Buildings \| Maximum
Noncontrolling Interest [Line Items]
Property, plant and equipment, useful life		40 years
Machinery and equipment \| Minimum
Noncontrolling Interest [Line Items]
Property, plant and equipment, useful life		5 years
Machinery and equipment \| Maximum
Noncontrolling Interest [Line Items]
Property, plant and equipment, useful life		20 years
Jungwoo Metal Ind. Co., LTD
Noncontrolling Interest [Line Items]
Non-controlling ownership interest		40.00%
Mueller Middle East BSC
Noncontrolling Interest [Line Items]
Non-controlling ownership interest		45.00%
Joining Systems Co. LLC
Noncontrolling Interest [Line Items]
Non-controlling ownership interest		40.00%