Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 26, 2020	Jun. 28, 2019	Jun. 26, 2020	Jun. 28, 2019
Statement of Comprehensive Income [Abstract]
Net Earnings	$ 28,832	$ 88,137	$ 101,650	$ 174,886
Components of other comprehensive income (loss)
Cumulative translation adjustment	6,756	1,232	2,079	2,401
Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment and Tax	2,446	1,910	5,195	4,037
Pension and postretirement medical liability adjustment	(554)	(423)	(1,169)	(893)
Other comprehensive income	8,648	2,719	6,105	5,545
Comprehensive Income	$ 37,480	$ 90,856	$ 107,755	$ 180,431

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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