6. Investment in National Beef Packing Company (Details - Investment rollforward) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 27, 2020	Jun. 29, 2019	Jun. 27, 2020	Jun. 29, 2019
Equity Method Investments and Joint Ventures [Abstract]
Beginning Investment Balance			$ 131,786
Equity in net income	$ 102,385	$ 25,194	115,484	$ 36,957
Distributions from National Beef Packing Company, LLC			(7,853)	$ (22,810)
Ending Investment Balance	$ 239,417		$ 239,417

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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