Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Jan. 29, 2017	Jan. 31, 2016	Jan. 25, 2015
Cash flows from operating activities:
Net income	$ 54,661	$ 11,497	$ 27,947
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	47,057	48,932	54,548
Intangible asset impairments	0	0	14,755
Effect of acquisition fair value adjustments	0	0	(929)
Accretion of deferred financing costs and debt discount	621	1,469	1,083
Write-off of deferred financing cost and debt discount	549	0	0
Deferred income taxes	2,185	(1,012)	27
Share-based compensation	30,828	20,468	29,629
(Gain) loss on disposition of business operations and assets (Note 11)	(25,489)	23	74
Earn-out liabilities	(215)	(16,362)	1,391
Contingencies	(1,518)	2,855	(65)
Corporate owned life insurance, net	770	(420)	358
Excess tax benefits on share-based compensation	0	0	(13)
Changes in assets and liabilities:
Accounts receivable, net	(7,403)	25,354	(2,968)
Inventories	(1,959)	10,262	(13,290)
Other assets	(7,516)	(657)	(4,714)
Accounts payable	3,101	4,980	(9,077)
Accrued liabilities	10,582	(12,945)	2,562
Deferred revenue	4,533	2,780	(1,419)
Income taxes payable	2,618	2,611	2,477
Other liabilities	4,207	2,241	3,784
Net cash provided by operating activities	117,612	102,076	106,160
Cash flows from investing activities:
Proceeds from sales and maturities of available-for-sale investments	0	0	3,674
Proceeds from sales of property, plant and equipment	48	0	89
Purchase of property, plant and equipment	(32,920)	(13,026)	(31,755)
Purchase of intangible assets	0	0	(1,100)
Purchase of investments	(13,198)	(14,630)	(7,148)
Acquisitions, net of cash acquired	0	(39,171)	(4,852)
Proceeds from disposition of business operations	32,000	0	0
Proceeds from sale of investments	555	0	0
Net cash used in investing activities	(13,515)	(66,827)	(41,092)
Cash flows from financing activities:
Proceeds from term loans	150,000	35,000	5,000
Payments of term loans	(80,875)	(30,750)	(43,749)
Proceeds from revolving line of credit	97,000	0	0
Payments of revolving line of credit	(181,000)	0	0
Deferred financing costs	(2,110)	0	0
Excess tax benefits on share-based compensation	0	0	13
Payments for employee stock-based compensation payroll taxes	(6,562)	(6,513)	(7,172)
Proceeds from exercise of stock options	5,779	5,807	8,880
Repurchase of outstanding common stock	(1,005)	(57,311)	(40,906)
Net cash used in financing activities	(18,773)	(53,767)	(77,934)
Net increase (decrease) in cash and cash equivalents	85,324	(18,518)	(12,866)
Cash and cash equivalents at beginning of period	211,810	230,328	243,194
Cash and cash equivalents at end of period	297,134	211,810	230,328
Supplemental disclosure of cash flow information
Income taxes paid	10,503	7,924	4,399
Interest paid	6,492	5,732	5,441
Capital expenditures	3,373	0	0
Convertible debt	$ 1,425	$ 0	$ 0