Investment in joint venture (Details) (USD $)	3 Months Ended
Apr. 30, 2015	Apr. 30, 2014	Jan. 31, 2015
Schedule of Equity Method Investments [Line Items]
date of investment in joint venture	Oct. 18, 2009
initial investment in joint venture	$ 5,900,000mfri_Initialinvestmentinjointventure
Payments to acquire interest in joint venture	2,000,000
Ownership percentage of joint venture	49.00%
Payments for advance to affiliate	3,900,000us-gaap_PaymentsForAdvanceToAffiliate
Income (loss) from joint venture	165,000	(8,000)
Equity Method Investment, Summarized Financial Information, Current Assets	9,588,000		13,820,000
Equity Method Investment, Summarized Financial Information, Noncurrent Assets	12,217,000		14,023,000
Equity Method Investment, Summarized Financial Information, Current Liabilities	2,529,000		4,499,000
Equity Method Investment, Summarized Financial Information, Noncurrent Liabilities	6,825,000		9,013,000
Equity Method Investment Summarized Financial Information, Equity	12,451,000		14,331,000
Equity Method Investment, Summarized Financial Information, Revenue	6,267,000	8,937,000
Equity Method Investment, Summarized Financial Information, Gross Profit	1,167,000	725,000
Equity Method Investment, Summarized Financial Information, Income from continuing operations	685,000	213,000
Equity Method Investment, Summarized Financial Information, Net income (loss)	$ 337,000	$ (16,000)

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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, including noncontrolling interest, reported by an 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 noncurrent liabilities 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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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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The cash outflow from advancing money to an affiliate (an entity that is related but not strictly controlled by the entity).

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