Significant accounting policies Investment in joint venture (Details) (USD $)	12 Months Ended
Jan. 31, 2015	Jan. 31, 2014
Schedule of Equity Method Investments [Line Items]
date of investment in joint venture	Oct. 18, 2009
Equity Method Investment, Aggregate Cost	$ 5,900,000mfri_IntialInvestmentInJointVenture
Payments to acquire interest in joint venture	2,000,000
Ownership percentage of joint venture	49.00%
Advances to joint venture	3,900,000us-gaap_AdvancesToAffiliate
loan to joint venture	(1,000,000)mfri_LoanToJointVenture
Income from joint venture	1,960,000	528,000
Equity Method Investment, Summarized Financial Information, Current Assets	13,820,000	13,034,000
Equity Method Investment, Summarized Financial Information, Noncurrent Assets	14,023,000	17,093,000
Equity Method Investment, Summarized Financial Information, Current Liabilities	4,499,000	2,921,000
Equity Method Investment, Summarized Financial Information, Noncurrent Liabilities	9,013,000	14,837,000
Equity Method Investment, Summarized Financial Information, Equity or Capital	14,331,000	12,369,000
Equity Method Investment, Summarized Financial Information, Revenue	40,397,000	29,110,000
Equity Method Investment, Summarized Financial Information, Gross Profit (Loss)	8,451,000	4,748,000
Equity Method Investment, Summarized Financial Information, Income (Loss) from Continuing Operations before Extraordinary Items	6,397,000	2,619,000
Equity Method Investment, Summarized Financial Information, Net Income (Loss)	$ 4,000,000	$ 1,078,000

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Long-Term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership. This does not include advances to clients.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The amount of current assets reported by an equity method investment of the entity.

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The amount of current liabilities reported by an equity method investment of the entity.

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Amount of equity, excluding noncontrolling interest, attributable to the equity method investment of the entity.

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The amount of gross profit (loss) reported by an equity method investment of the entity.

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The amount of income (loss) from continuing operations before extraordinary items reported by an equity method investment of the entity.

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The amount of net income (loss) reported by an equity method investment of the entity.

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The amount of noncurrent assets reported by an equity method investment of the entity.

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The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity.

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