BUSINESS COMBINATIONS (Detail) - Schedule of Recognized Identified Assets Acquired and Liabilities Assumed (USD $) In Thousands, unless otherwise specified	12 Months Ended
Jan. 31, 2013	Jan. 31, 2012
Consideration transferred:
Cash	$ 10,413
Fair value of non-controlling interest	955
Fair value of 48% equity method investment	18,642
	30,010
Net assets acquired:
Cash	24,971
Accounts receivable	7,381
Inventory	8,491
Prepaid expenses and other current assets	711
Other assets	2,995
Property, plant and equipment	78,618
Current liabilities	(19,167)
Long-term debt	(65,000)
	39,000
Bargain purchase gain	$ 8,990	$ 3,541

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Amount of cash paid to acquire the entity.

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The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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The total purchase price of the acquired entity. This includes cash paid to equity interest holders of the acquired entity, fair value of debt and equity securities issued to equity holders of the acquired entity, and transaction costs paid to third parties to consummate the acquisition.

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The amount of cash and cash equivalents acquired in a business combination.

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The amount of acquisition cost of a business combination allocated to inventory, including finished goods, work-in-process, and raw materials.

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The amount of acquisition cost of a business combination allocated to receivables.

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The amount of acquisition cost of a business combination allocated to current liabilities of the acquired entity.

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Amount of acquisition cost of a business combination allocated to noncontrolling interests.

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The amount of acquisition cost of a business combination allocated to notes payables and long-term debt assumed from the acquired entity.

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Amount of acquisition cost of a business combination allocated to other noncurrent assets not separately disclosed.

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The amount of acquisition cost of a business combination allocated to property, plant and equipment to be used in ongoing operations.

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In a business combination in which the amount of net identifiable assets acquired and liabilities assumed exceeds the aggregate consideration transferred or to be transferred (as defined), this element represents the amount of gain recognized by the entity.

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In a business combination achieved in stages, this element represents the acquisition-date fair value of the equity interest in the acquiree held by the acquirer immediately before the acquisition date.

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