Commitments and Contingencies - Additional Information (Detail)			1 Months Ended			3 Months Ended
		Dec. 09, 2015 USD ($)	Oct. 31, 2015 ft²	Sep. 30, 2015 Patent	Jul. 31, 2013 ft²	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($) ft²	Jun. 30, 2016 EUR (€) ft²	Dec. 31, 2015 USD ($)	Apr. 30, 2014 USD ($)
Commitments and Contingencies [Line Items]
Office space under operating lease | ft²							125,560	125,560
Purchase price of property amount		$ 16,500,000
License agreement, upfront payment									$ 500,000	$ 1,500,000
License agreement, maximum agreed additional payments upon achievement of development milestones										$ 4,500,000
License agreement, milestone payment									$ 600,000
Patents allegedly infringed upon, number | Patent				2
Subsequent Event
Commitments and Contingencies [Line Items]
Termination fee						$ 200,000
Europe
Commitments and Contingencies [Line Items]
Facilities leases, base rent per month							$ 72,000	€ 64,500
Lease Agreements | Europe
Commitments and Contingencies [Line Items]
Office space under operating lease | ft²					33,000
Lease, expiration date					Jul. 31, 2023
Additional office space under operating lease | ft²	[1]		9,000
Lease Agreement Adjacent To Aachen Facility | Europe
Commitments and Contingencies [Line Items]
Office space under operating lease | ft²			30,000
Lease, expiration date			Jun. 30, 2017
For March 2016 through February 2018
Commitments and Contingencies [Line Items]
Facilities leases, base rent per month							84,914
For March 2018 through February 2021
Commitments and Contingencies [Line Items]
Facilities leases, base rent per month							$ 87,530

[1] 9,000