Related Parties - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended		1 Months Ended		3 Months Ended		6 Months Ended		0 Months Ended	1 Months Ended		3 Months Ended	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2012 Transitional Services Agreement [Member]	Dec. 31, 2012 R&D Services Agreement [Member]	Jun. 30, 2014 R&D Services Agreement [Member]	Jun. 30, 2013 R&D Services Agreement [Member]	Jun. 30, 2014 R&D Services Agreement [Member]	Jun. 30, 2013 R&D Services Agreement [Member]	Dec. 20, 2012 Elan	Dec. 31, 2012 Elan Transitional Services Agreement [Member]	Feb. 28, 2014 Ordinary Shares Perrigo	Jun. 30, 2014 Director [Member] Consulting [Member]	Jun. 30, 2014 Director [Member] Consulting [Member]
Related Party Transaction [Line Items]
Percentage of voting interests acquired											18.00%
Issuance of ordinary shares to Elan, shares											3,182,253
Shares sold pursuant to underwritten public offering													3,182,253
Share price (in dollars per share)													$ 26
Additional percentage of employee service payment					40.00%							40.00%
Research and development service agreement (in years)						2 years
Fixed service fee, annual rate						$ 500,000
Fixed service fee per employee, annual rate						250,000
Variable service fee, annual rate						250,000
Percentage of mark-up applied to fixed and variable charge						10.00%
Fixed monthly charge for lab space and capital equipment used						7,500
Revenues	137,000	167,000	275,000	338,000			137,000	167,000	275,000	338,000
Amount paid to related party														$ 20,000	$ 20,000