Amount of assumed costs and earnings in excess of billings.

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Amount of liabilities accrued for goods and services received that were used in an entity's business and related party payables, assumed at the acquisition date.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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PURCHASE OF ATLANTIC PROJECTS COMPANY LIMITED - fair value of assets and liabilities acquired (Details 3) - Finite-Lived Intangible Assets, Major Class Name [Domain] - USD ($)	May. 29, 2015	Jul. 31, 2015	Jan. 31, 2015	Jul. 31, 2014
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Goodwill		$ 22,887,000	$ 18,476,000	$ 18,476,000
Atlantic Projects Company Limited [Member]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Cash	$ 2,274,000
Accounts receivable	5,735,000
Costs and estimated earnings in excess of billings	3,177,000
Prepaid expenses and other assets	592,000
Property, plant and equipment	1,303,000
Customer contracts	182,000
Goodwill	4,411,000
Less - accounts payable	628,000
Less - accrued expenses (including cash dividends payable)	5,201,000
Less - deferred taxes and other liabilities	744,000
Net assets acquired	$ 11,101,000
Atlantic Projects Company Limited [Member] \| Maximum [Member]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Useful life	1 year