Stock-based Compensation - Summary of Stock Option Activity (Detail)	12 Months Ended
	Dec. 31, 2016 USD ($) $ / shares shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Total Number of Shares, Beginning Balance | shares	332,400
Total Number of Shares, Granted | shares	58,569
Total Number of Shares, Exercised | shares	0
Total Number of Shares, Cancelled | shares	(16,523)
Total Number of Shares, Ending Balance | shares	374,446
Total Number of Shares, Exercisable | shares	304,880
Weighted-Average Exercise Price Per Share, Beginning Balance | $ / shares	$ 30.50
Weighted-Average Exercise Price Per Share, Granted | $ / shares	2.91
Weighted-Average Exercise Price Per Share, Exercised | $ / shares	0
Weighted-Average Exercise Price Per Share, Cancelled | $ / shares	5.88
Weighted-Average Exercise Price Per Share, Ending Balance | $ / shares	27.29
Weighted-Average Exercise Price Per Share, Exercisable | $ / shares	$ 30.93
Weighted-Average Remaining Contractual Term, Ending Balance	6 years 1 month 21 days
Weighted-Average Remaining Contractual Term, Exercisable	5 years 7 months 10 days
Aggregate Intrinsic Value, Ending Balance | $	$ 0
Aggregate Intrinsic Value, Exercisable | $	$ 0