Accrued Liabilities - Summary (Details) - USD ($) $ in Thousands	Jan. 26, 2020	Jan. 27, 2019
Payables and Accruals [Abstract]
Compensation	$ 20,817	$ 34,987
Contract liabilities (ASC 606)	8,581	10,073
Lease liabilities (ASC 842)	3,273	0
Earn-out liability	2,108	3,276
Professional fees	2,449	2,336
Deferred revenue	3,931	3,439
Deferred compensation	1,365	2,203
Income taxes payable	0	2,105
Environmental reserve	1,450	1,460
Other	6,658	8,583
Accrued liabilities	$ 50,632	$ 68,462

Accrued Sales and Marketing Expenses Current

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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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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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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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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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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