INCOME TAXES (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018
Earnings before income taxes and equity in earnings of nonconsolidated subsidiaries
United States	$ 169,281	$ 166,108	$ 137,744
Foreign	23,487	33,750	15,589
Earnings before income taxes and equity in earnings of nonconsolidated subsidiaries	192,768	199,858	153,333
Current:
Federal	30,431	27,809	21,106
State	8,302	5,568	6,585
Foreign	12,730	13,130	17,559
Total	51,463	46,507	45,250
Non-current:	(451)	(240)	(456)
Deferred:
Federal	(6,086)	47	2,290
State	(822)	160	405
Foreign	5,511	1,279	(1,881)
Total	(1,397)	1,486	814
Total income tax expense (benefit)	$ 49,615	$ 47,753	$ 45,608
Reconciliations of statutory federal income tax rate and effective tax rate
Statutory federal income tax rate	21.00%	21.00%	21.00%
State income taxes, net of federal benefit	3.50%	2.50%	3.50%
Carryforwards, credits and changes in valuation allowances	(1.60%)	(1.00%)	3.20%
Foreign tax rate differences	(1.70%)	0.30%	(1.00%)
Changes in unrecognized tax benefits	0.20%	(0.10%)	(0.30%)
Goodwill and intangible impairment	2.40%	0.00%	2.20%
Effects of 2017 Tax Act	0.00%	0.00%	(0.50%)
Other	1.90%	1.20%	1.70%
Total	25.70%	23.90%	29.70%
Deferred income tax assets:
Accrued expenses and allowances	$ 17,203	$ 16,148
Tax credits and loss carryforwards	81,912	64,116
Defined benefit pension liability	30,623	35,539
Accrued compensation and benefits	23,545	14,122
Lease liabilities	23,715	21,763
Deferred compensation	13,883	15,174
Gross deferred income tax assets	190,881	166,862
Valuation allowance	(44,451)	(35,215)
Net deferred income tax assets	146,430	131,647
Deferred income tax liabilities:
Property, plant and equipment	35,701	31,628
Intangible assets	43,699	49,686
Inventory allowances	5,705	5,352
Lease assets	23,715	22,066
Other deferred tax liabilities	5,248	6,067
Total deferred income tax liabilities	114,068	114,799
Net deferred income tax asset	32,362	16,848
Deferred income tax assets (liabilities), Balance Sheet Caption
Other assets	74,051	75,754
Deferred income taxes	(41,689)	(58,906)
Net deferred income tax asset	32,362	16,848
Income tax expense due to nondeductible goodwill impairment	4,651		$ 3,171
Income tax expense due to nondeductible restructuring charges	1,100		6,756
Tax credit and net operating loss carryforwards related to the defined benefit pension obligation	81,912	64,116
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Gross Unrecognized Tax Benefits beginning of year	2,300	2,599
Gross increases—tax positions in prior period	0	29
Gross decreases—tax positions in prior period	(1)	0
Gross increases—current‑period tax positions	398	593
Settlements with taxing authorities	(183)	(150)
Lapse of statute of limitations	(650)	(771)
Gross Unrecognized Tax Benefits end of year	1,864	2,300	$ 2,599
Uncertain tax positions for which reversal is reasonably possible during the next 12 months	973
Reduction of income tax expense, due to expiration of statutes of limitation	513	609
Accrued interest and penalties relating to unrecognized tax benefits	845	178
Unrecognized tax benefits that, if recognized, would affect effective tax rate	$ 2,547	$ 2,224