Summarized Unaudited Financial Information for AquaBounty (Detail) (AquaBounty [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012
AquaBounty [Member]
Schedule of Equity Method Investments [Line Items]
Current assets	$ 514
Non-current assets	1,962
Total assets	2,476
Current liabilities	706
Non-current liabilities	2,741
Total liabilities	3,447
Net liabilities	(971)
Revenues
Operating expenses	578
Loss from operations	(578)
Other expense	(1)
Net loss	$ (579)

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

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

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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 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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The amount of operating expenses reported by an equity method investment of the entity.

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