Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Oct. 25, 2015	Oct. 26, 2014
Cash flows from operating activities:
Net income	$ 10,250	$ 43,388
Adjustments to reconcile net income to net cash provided by operating activities, net of effects of acquisitions:
Depreciation, amortization and impairments	36,534	36,247
Accretion of deferred financing costs and debt discount	1,054	789
Deferred income taxes	4,366	6,519
Stock-based compensation	13,398	21,056
Earn-out liabilities	(13,618)	(228)
Environmental reserve	2,855	(58)
Loss on disposition of property, plant and equipment	23	0
Changes in assets and liabilities:
Accounts receivable, net	14,577	(11,990)
Inventories	2,694	(44)
Prepaid expenses and other assets	5,975	(1,804)
Accounts payable	677	(94)
Accrued liabilities	(15,631)	755
Deferred revenue	1,033	592
Income taxes payable and prepaid taxes	2,086	(2,095)
Other liabilities	1,343	1,496
Net cash provided by operating activities	67,616	94,529
Cash flows from investing activities:
Proceeds from sales and maturities of available-for-sale investments	0	3,124
Proceeds from sales of property, plant and equipment	0	71
Purchase of property, plant and equipment	(10,705)	(25,459)
Purchase of intangible assets	0	(1,000)
Acquisitions, net of cash acquired	(44,432)	0
Purchases of other investments	(5,230)	(3,648)
Proceeds from sale of equity investments	5,261	0
Net cash used in investing activities	(55,106)	(26,912)
Cash flows from financing activities:
Borrowings under line of credit	35,000	0
Payment for employee stock-based compensation payroll taxes	(6,070)	(6,309)
Proceeds from exercises of stock options	3,965	7,952
Repurchase of outstanding common stock	(57,311)	(40,906)
Payment of long term debt	(26,063)	(39,062)
Net cash used in financing activities	(50,479)	(78,325)
Net decrease in cash and cash equivalents	(37,969)	(10,708)
Cash and cash equivalents at beginning of period	230,328	243,194
Cash and cash equivalents at end of period	$ 192,359	$ 232,486