Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2016	Jan. 25, 2015	Jan. 26, 2014
Cash flows from operating activities:
Net income (loss)	$ 11,497	$ 27,947	$ (164,466)
Adjustments to reconcile net income (loss) to net cash provided by operating activities, net of effects of acquisitions:
Depreciation, amortization and impairments	48,932	69,303	94,073
Impairment - goodwill	0	0	116,686
Effect of acquisition fair value adjustments	0	(929)	2,529
Accretion of deferred financing costs and debt discount	1,469	1,083	1,509
Write-off of deferred financing costs and debt discount	0	0	7,093
Deferred income taxes	(1,012)	27	29,987
Stock-based compensation	20,468	29,629	24,589
Earn-out liabilities	(16,362)	1,391	(654)
Environmental reserve	2,855	(65)	0
Excess tax benefits on stock based compensation	0	(13)	(4,220)
Loss (gain) on disposition of property, plant and equipment	23	74	(28)
Changes in assets and liabilities:
Accounts receivable, net	25,354	(2,968)	2,827
Inventories	10,262	(13,290)	12,238
Prepaid expenses and other assets	619	(5,902)	623
Accounts payable	4,980	(9,077)	(11,294)
Accrued liabilities	(12,945)	2,562	(2,739)
Deferred revenue	2,780	(1,419)	3,401
Income taxes payable and prepaid taxes	2,611	2,477	1,825
Other liabilities	545	5,330	4,002
Net cash provided by operating activities	102,076	106,160	117,981
Cash flows from investing activities:
Purchases of available-for-sale investments	0	0	(1,050)
Proceeds from sales and maturities of available-for-sale investments	0	3,674	10,249
Proceeds from sales of property, plant and equipment	0	89	57
Purchase of property, plant and equipment	(13,026)	(31,755)	(37,161)
Purchase of intangible assets	0	(1,100)	(3,533)
Purchase of cost method investment	(14,630)	(7,148)	(2,500)
Acquisitions, net of cash acquired	(39,171)	(4,852)	0
Net cash used in investing activities	(66,827)	(41,092)	(33,938)
Cash flows from financing activities:
Proceeds from debt issuance, net of discount	35,000	5,000	327,344
Deferred financing cost	0	0	(2,980)
Excess tax benefits on stock based compensation	0	13	4,220
Payments for employee stock-based compensation payroll taxes	(6,513)	(7,172)	(10,522)
Proceeds from exercises of stock options	5,807	8,880	16,398
Repurchase of outstanding common stock	(57,311)	(40,906)	(30,000)
Payment of long term debt	(30,750)	(43,749)	(368,501)
Net cash used in financing activities	(53,767)	(77,934)	(64,041)
Effect of exchange rate increase on cash and cash equivalents	0	0	0
Net (decrease) increase in cash and cash equivalents	(18,518)	(12,866)	20,002
Cash and cash equivalents at beginning of period	230,328	243,194	223,192
Cash and cash equivalents at end of period	211,810	230,328	243,194
Supplemental disclosure of cash flow information
Income taxes paid	7,924	4,399	7,227
Interest paid	$ 5,732	$ 5,441	$ 8,727