Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 25, 2021	Sep. 26, 2020
OPERATING ACTIVITIES
Net income	$ 268,209	$ 127,035
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of operating property and intangible assets	36,532	34,212
Non-cash interest charges	336	222
Provisions for losses on trade and other accounts receivable	3,884	7,206
Gains on sales/disposals of operating property	(1,259)	(2,295)
Impairment of intangible and other assets	0	2,582
Deferred income taxes, net	4,948	4,758
Stock-based compensation	18,717	2,691
Changes in operating assets and liabilities:
Increase in trade and other accounts receivable	(224,503)	(62,492)
Increase in other assets	(3,822)	(13,492)
Increase in accounts payable	167,880	66,815
Increase in other liabilities	22,837	14,050
(Decrease) increase in insurance claims	(76,769)	4,256
NET CASH PROVIDED BY OPERATING ACTIVITIES	216,990	185,548
INVESTING ACTIVITIES
Net changes in other short-term investments	0	131
Sales and maturities of investments	25,521	18,795
Purchases of investments	(77,649)	(21,102)
Purchases of operating property	(18,561)	(25,426)
Proceeds from sales of operating property	2,047	6,623
Consideration paid for acquisition	0	(2,766)
NET CASH USED BY INVESTING ACTIVITIES	(68,642)	(23,745)
FINANCING ACTIVITIES
Increase (decrease) in cash overdraft	14,210	(6,419)
Dividends paid	(102,463)	(101,442)
Payment for debt issue costs	0	(959)
Proceeds from exercises of stock options	134	676
Taxes paid in lieu of shares issued related to stock-based compensation plans	(2,342)	(3,326)
Purchases of common stock	(50,230)	(115,962)
Principal payments on finance lease obligations	(26,513)	(33,036)
Payment of deferred consideration	(168)	0
NET CASH USED BY FINANCING ACTIVITIES	(167,372)	(260,468)
Effect of exchange rate changes on cash and cash equivalents	234	(2,296)
Decrease in cash and cash equivalents	(18,790)	(100,961)
Cash and cash equivalents at beginning of period	249,354	319,515
Cash and cash equivalents at end of period	$ 230,564	$ 218,554