Effective income tax reconciliation effect of Tax Cuts and Jobs Act.

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Operating loss carryforwards begin expiring year.

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Amount of increase (decrease) in additional paid in capital (APIC) resulting from a tax benefit (deficiency) associated with an share-based compensation plan other than an employee stock ownership plan (ESOP).

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Income Taxes - Additional Information (Detail) - USD ($)	1 Months Ended	11 Months Ended	12 Months Ended
	Feb. 03, 2018	Dec. 31, 2017	Feb. 03, 2018	Jan. 28, 2017	Jan. 30, 2016
Income Tax Examination [Line Items]
Federal tax at statutory rate	21.00%	35.00%	33.80%	35.00%	35.00%
Valuation allowance	$ 2,384,000		$ 2,384,000
Realized excess tax benefits (shortfall) related to share-based compensation plans				$ (874,000)	$ 3,646,000
Effect of enacted Tax Cuts and jobs act on effective tax rate			1.80%
Unrecognized tax benefit	0		$ 0
Maximum [Member]
Income Tax Examination [Line Items]
Interest and penalties related to unrecognized tax benefits			100,000	100,000	100,000
Accrued interest and accrued penalties related to unrecognized tax benefits	100,000		100,000	$ 100,000	$ 100,000
State and Local Jurisdiction [Member]
Income Tax Examination [Line Items]
Gross operating loss carry forward	25,300,000		$ 25,300,000
Operating loss carry forward, expiration year			2023
Domestic Tax Authority [Member]
Income Tax Examination [Line Items]
Gross operating loss carry forward	$ 14,800,000		$ 14,800,000