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SIGNIFICANT ACCOUNTING POLICIES - PP&E, Assets held for Sale, Intangibles, Investments, Segments and Compensation (Details)		12 Months Ended
	Sep. 13, 2018 USD ($)	Dec. 29, 2019 USD ($) segment company property item	Dec. 30, 2018 USD ($) property
Depreciation
Property, plant and equipment, gross		$ 736,390,000	$ 808,689,000
Less accumulated depreciation		(532,815,000)	(574,997,000)
Property, plant and equipment, net		203,575,000	233,692,000
Depreciation expense		21,900,000	28,600,000
Accelerated depreciation incurred		$ 300,000	$ 600,000
Assets held for sale
Number of properties with assets held for sale \| property		5	3
Number of properties actively marketed to be sold \| property		5
Number of media companies with assets held for sale \| company		4
Facilities with reduced carrying value \| property		1
Impairment charge of assets held for sale		$ 700,000
Gain (loss) on sale of property		$ 3,300,000
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
Distributions received relates to cost or equity method investees		$ 1,295,000	2,876,000
Gains related to investments in unconsolidated companies			1,721,000
California, Washington and the Central region
Segment reporting
Number of operating segments \| segment		1
Career Builder LLC
Investments in unconsolidated companies
Distributions received relates to cost or equity method investees			$ 2,800,000
Ownership interest (as a percent)	3.00%		3.00%
Proceeds from sale	$ 5,300,000
Land
Depreciation
Property, plant and equipment, gross		$ 27,869,000	$ 32,335,000
Buildings and improvements
Depreciation
Property, plant and equipment, gross		$ 245,748,000	268,157,000
Buildings and improvements \| Minimum
Depreciation
Estimated Useful Lives		5 years
Buildings and improvements \| Maximum
Depreciation
Estimated Useful Lives		60 years
Equipment
Depreciation
Property, plant and equipment, gross		$ 462,449,000	506,307,000
Equipment \| Minimum
Depreciation
Estimated Useful Lives		2 years
Equipment \| Maximum
Depreciation
Estimated Useful Lives		25 years
Construction in process
Depreciation
Property, plant and equipment, gross		$ 324,000	$ 1,890,000
Presses \| Minimum
Depreciation
Estimated Useful Lives		9 years
Presses \| Maximum
Depreciation
Estimated Useful Lives		25 years
Other equipment \| Minimum
Depreciation
Estimated Useful Lives		2 years
Other equipment \| Maximum
Depreciation
Estimated Useful Lives		15 years