Costs and estimated earnings on uncompleted contracts Costs and estimated earnings on uncompleted contracts (Details) (USD $) In Thousands, unless otherwise specified	Jan. 31, 2015	Jan. 31, 2014
Costs incurred on uncompleted contracts
Costs incurred on uncompleted contracts	$ 66,547	$ 52,064
Estimated earnings	31,082mfri_EstimatedEarnings	18,915mfri_EstimatedEarnings
Earned revenue	97,629us-gaap_DeferredRevenue	70,979us-gaap_DeferredRevenue
Billings to date	97,610mfri_BillingsToDate	71,725mfri_BillingsToDate
Costs in excess of billings, net	19mfri_CostsInExcessOfBillingsNet	(746)mfri_CostsInExcessOfBillingsNet
Costs and estimated earnings in excess of billings on uncompleted contracts	700	1,476
Billings in excess of costs and estimated earnings on uncompleted contracts	$ (681)us-gaap_BillingsInExcessOfCost	$ (2,222)us-gaap_BillingsInExcessOfCost

Billings to date related to percentage of completion

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Costs incurred on uncompleted contracts related to percentage of completion

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Costs in excess of billings, net related to percentage of completion

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Liability attributable to (i) billings in excess of costs under the percentage of completion contract accounting method representing the difference between contractually invoiced amounts (billings) and revenue recognized based, for example, on costs incurred to estimated total costs at period end or (ii) contractually invoiced amounts (billings) in excess of costs incurred and accumulated under the completed contract accounting method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 35

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Amount of receivable reflecting the cost incurred on uncompleted contracts in excess of related billings.

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Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

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