Commitments and Contingencies - Additional Information (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Feb. 28, 2013 Extension	Dec. 31, 2018 USD ($) Litigation	Dec. 31, 2017 USD ($)
Commitments And Contingencies Disclosure [Abstract]
Operating leases term of contract	3 years
Operating lease term, number of additional extensions allowed | Extension	2
Operating lease extension period	3 years
Annual rent expense for leased facilities		$ 1,081	$ 1,130
Annual rental expense under operating lease agreements		$ 60	$ 48
Number of pending litigation | Litigation		0