Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax [Line Items]
Total domestic loss before income taxes	$ 83,256,000	$ 39,250,000
Total foreign loss before income taxes	2,463,000	1,658,000
Income tax benefit	103,000	0	0
Deferred income tax benefit recognized	0	0	0
Federal corporate income tax rate	34.00%	34.00%	34.00%
Operating losses subject to annual limits	16,400,000
Annual usage limit of operating loss carryforwards	1,500,000
Net operating losses inherited via acquisition	19,100,000
Federal and state research and development tax credits	9,661,000	10,062,000
Undistributed earnings of foreign subsidiary	196,000
Domestic
Income Tax [Line Items]
Operating loss carryforwards	254,528,000
Federal and state research and development tax credits	6,770,000
Expiration date of Federal income tax loss carryforwards	2022
Foreign
Income Tax [Line Items]
Income tax benefit	103,000
Operating loss carryforwards	11,800,000
Share Based Compensation | Domestic
Income Tax [Line Items]
Operating loss carryforwards	8,856,000
AquaBounty Technologies, Inc.
Income Tax [Line Items]
Annual usage limit of operating loss carryforwards	900,000
Federal and state research and development tax credits	2,600,000
Expiration date of Federal income tax loss carryforwards	2018
AquaBounty Technologies, Inc. | Domestic
Income Tax [Line Items]
Operating loss carryforwards	12,500,000
AquaBounty Technologies, Inc. | Foreign
Income Tax [Line Items]
Operating loss carryforwards	$ 4,600,000