Redeemable Preferred Stock - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Sale of Stock [Line Items]
Redeemable preferred stock carrying value	$ 23,603	$ 23,603
Redeemable preferred stock authorized	20,000,000	20,000,000
Redeemable preferred stock, price per share	$ 0.0001	$ 0.0001
Redeemable Preferred Stock [Member]
Sale of Stock [Line Items]
Redeemable preferred stock carrying value	$ 23,600
Redeemable preferred stock authorized	20,000,000
Redeemable preferred stock redemption, price per share	$ 9.00
Redeemable preferred stock, price per share	$ 7.11	$ 7.11