SIGNIFICANT ACCOUNTING POLICIES - PP&E, Assets held for Sale, Intangibles, Investments, Segments and Compensation (Details)	3 Months Ended	12 Months Ended
Mar. 29, 2020 USD ($) segment company property item	Mar. 31, 2019 USD ($) property	Dec. 29, 2019 property
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Depreciation expense	$ 14,768,000	$ 5,717,000
Accelerated depreciation incurred	$ 10,000,000	$ 0
Assets held for sale
Number of properties with assets held for sale \| property	6		5
Number of properties actively marketed to be sold \| property	1
Number of media companies with assets held for sale \| company	1
Facilities with reduced carrying value \| property		1
Impairment charge of assets held for sale	$ 0	$ 700,000
Segment reporting
Number of operating segments \| segment	2
Goodwill and intangible impairment
Impairment of Intangible Assets, Finite-lived	$ 0	0
Stock-based compensation
Number of stock-based compensation plans \| item	2
Investments in unconsolidated companies
Impairments related to investments in unconsolidated companies	$ 0	$ 0

Represents the number of facilities were their carrying value was reduced to their estimated fair value less costs.

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Represents the number of media companies at which assets are held for sale.

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Number of properties actively marketed to be sold.

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Represents the number of properties classified as assets held for sale.

+ References

No definition available.

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The number of stock-based compensation plans approved by the entity's shareholders.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Amount of accelerated depreciation charged against earnings associated with exit from or disposal of business activities or restructuring plan.

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