Accrued Liabilities (Summary of Accrued Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Jan. 25, 2015	Jan. 26, 2014	Jan. 27, 2013
Payables and Accruals [Abstract]
Compensation	$ 20,642us-gaap_AccruedEmployeeBenefitsCurrent	$ 17,875us-gaap_AccruedEmployeeBenefitsCurrent
Equity awards accounted for as a liability	718	917
Deferred compensation	527	1,478
Accrued sales and marketing expenses	5,028	2,227
Accrued professional fees	4,019us-gaap_AccruedProfessionalFeesCurrent	3,990us-gaap_AccruedProfessionalFeesCurrent
Accrued interest expense	93us-gaap_InterestPayableCurrent	287us-gaap_InterestPayableCurrent
Income taxes payable	6,153us-gaap_AccruedIncomeTaxesCurrent	3,675us-gaap_AccruedIncomeTaxesCurrent
Accrued taxes	32	49
Accrued restructuring	282us-gaap_RestructuringReserve	2,632us-gaap_RestructuringReserve	0us-gaap_RestructuringReserve
Other	12,260us-gaap_OtherAccruedLiabilitiesCurrent	11,018us-gaap_OtherAccruedLiabilitiesCurrent
Total accrued liabilities, current	$ 49,754us-gaap_AccruedLiabilitiesCurrent	$ 44,148us-gaap_AccruedLiabilitiesCurrent

Accrued Sales and Marketing Expenses Current

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Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations, excluding pension and other postretirement benefits, incurred through that date and payable for perquisites provided to employees pertaining to services received from them. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable within one year (or the operating cycle, if longer). Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable within one year (or the operating cycle, if longer).

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Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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