SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Inventories (Details) - USD ($) $ in Thousands	Jun. 27, 2020	Dec. 28, 2019	Dec. 29, 2018
Inventory, Net [Abstract]
Raw materials and purchased parts	$ 167,626	$ 158,314
Work-in-process	32,535	38,088
Finished goods and manufactured goods	249,355	221,968
Total	449,516	418,370
Retained earnings	$ 2,194,916	2,173,802
Cumulative Effect, Period of Adoption, Adjustment
Inventory, Net [Abstract]
Retained earnings		$ 32,854	$ 40,215

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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