Income Taxes - Schedule of Tax Effects of Temporary Differences that Gave Rise to Deferred Tax Assets and Liabilities (Detail) (USD $)	Apr. 30, 2015	Jan. 31, 2015
Assets:
Stock options	$ 1,816,000	$ 1,649,000
Purchased intangibles	1,106,000	1,132,000
Accrued liabilities	337,000	428,000
Other	283,000us-gaap_DeferredTaxAssetsOther	107,000us-gaap_DeferredTaxAssetsOther
Total Asset	3,542,000us-gaap_DeferredTaxAssetsGross	3,316,000us-gaap_DeferredTaxAssetsGross
Liabilities:
Purchased intangibles	(3,048,000)	(2,931,000)
Construction contracts	(842,000)	(830,000)
Property and equipment	(503,000)	(533,000)
Other	(30,000)us-gaap_DeferredTaxLiabilitiesOther	(32,000)us-gaap_DeferredTaxLiabilitiesOther
Total Liabilities	(4,423,000)us-gaap_DeferredIncomeTaxLiabilities	(4,326,000)us-gaap_DeferredIncomeTaxLiabilities
Net deferred tax liabilities	$ (881,000)us-gaap_DeferredTaxAssetsLiabilitiesNet	$ (1,010,000)us-gaap_DeferredTaxAssetsLiabilitiesNet

Deferred tax liabilities construction contracts.

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Amount of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from intangible assets including goodwill.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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