Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

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This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to inventory acquired in connection with a business combination for which the initial accounting was incomplete.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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The increase (decrease) during the reporting period in the value of coal held in inventory.

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The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value.

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Amount of noncash expense (reversal of expense) for pension benefits. Excludes other postretirement benefits.

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Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation.

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Selected Quarterly Financial Data - Narrative (Details) - USD ($) $ in Thousands			3 Months Ended								6 Months Ended	12 Months Ended
	Nov. 30, 2021	Jan. 28, 2021	Jan. 01, 2022	Sep. 25, 2021	Jun. 26, 2021	Mar. 27, 2021	Dec. 26, 2020	Sep. 26, 2020	Jun. 27, 2020	Mar. 28, 2020	Jun. 26, 2021	Jan. 01, 2022	Dec. 26, 2020	Dec. 28, 2019
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment
Non-cash pension settlement charges			$ 19,900									$ 19,855	$ 0	$ 0
Gain on sale of building			4,100			$ 1,900
Integration cost			3,600	$ 2,000	$ 500	800	$ 700	$ 300	$ 100
Asset retirement expense			700						200
Restructuring costs			200			400				$ 4,000
Increase to coal mining reserve			200						1,800
Restructuring, impairment and other costs				800			$ 800	1,300	1,800			2,158	41,716	13,033
Impairment charges				$ 100	500			$ 100				0	36,078	322
Other asset impairment charges									$ 33,800
Electronics
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment
Restructuring, impairment and other costs					800							1,124	2,540	5,501
Impairment charges													$ 0	$ 0
Carling Technologies
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment
Inventory adjustment	$ 6,400		$ 1,600
Hartland Controls
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment
Inventory adjustment		$ 6,800			3,300	$ 3,500
Hartland Controls \| Electronics
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment
Gain (loss) on sale of properties					$ (1,000)						$ 900	$ 5,000