Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2013	Dec. 31, 2016
Commitments And Contingencies Disclosure [Abstract]
Incentive awarded to the company by the State of Connecticut, total	$ 9.0		$ 11.5
Incentive awarded to the company by the State of Connecticut, non-interest bearing loans	7.0		8.0
Incentive awarded to the company by the State of Connecticut, grants	$ 2.0		$ 3.5
Non-interest bearing incentive loan term	10 years
Forgiveness awarded to the company by the state of Connecticut	$ 6.0
Incentive awarded to the company by the State of Connecticut, revenue recognized	0.3	$ 0.4
Incentive awarded to the company by the State of Connecticut, deferred revenue	$ 4.6			$ 4.8