CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Oct. 26, 2019	Oct. 24, 2020	Oct. 26, 2019
Cash flows from operating activities:
Net income	$ 24,229	$ 38,532	$ 68,404
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	47,356	132,313	140,941
Non-cash lease expense		23,480	22,263
Deferred income tax (benefit) provision		(20,478)	7,189
Stock-based compensation		10,490	8,450
Amortization of debt discount		6,732	15,016
Provision for bad debt (recovery), net	3,498	353	(7,015)
Gain on sale of fixed assets	(2,241)	(9,207)	(13,785)
Gain on debt extinguishment		(12,046)	0
Amortization of debt issuance costs and other		2,189	2,997
Goodwill impairment charge		53,264	0
Change in operating assets and liabilities, net of acquisitions:
Accounts receivable, net		(122,520)	(297,573)
Contract assets, net		48,568	(122,514)
Other current assets and inventories		20,670	(13,795)
Other assets		5,212	39,219
Income taxes receivable/payable		10,513	12,256
Accounts payable		68,731	13,810
Accrued liabilities, insurance claims, operating lease liabilities, and other liabilities		22,629	(9,616)
Net cash provided by (used in) operating activities		279,425	(133,753)
Cash flows from investing activities:
Capital expenditures		(36,110)	(101,858)
Proceeds from sale of assets		11,859	16,169
Other investing activities		0	306
Net cash used in investing activities		(24,251)	(85,383)
Cash flows from financing activities:
Proceeds from borrowings on senior credit agreement, including term loans		773,000	345,000
Principal payments on senior credit agreement, including term loans		(704,875)	(242,000)
Extinguishment of 0.75% senior notes	0	(401,736)
Redemption discount on convertible debt, net of costs	0	30,761
Settlement of convertible note hedges related to extinguished convertible debt	0	7,197
Purchase of warrants	0	(7,176)
Exercise of stock options		5,425	313
Restricted stock tax withholdings		(500)	(1,182)
Net cash (used in) provided by financing activities		(297,904)	102,131
Net decrease in cash and equivalents and restricted cash		(42,730)	(117,005)
Cash, cash equivalents and restricted cash at beginning of period		59,869	134,151
Cash, cash equivalents and restricted cash at end of period	$ 17,146	17,139	17,146
Supplemental disclosure of other cash flow activities and non-cash investing and financing activities:
Cash paid for interest		17,652	19,966
Cash paid for taxes, net		38,309	6,588
Purchases of capital assets included in accounts payable or other accrued liabilities at period end		$ 3,726	$ 2,247