Registration of securities issued in business combination transactions

Fair Value Measurements - Additional Information (Detail)

v3.7.0.1
Fair Value Measurements - Additional Information (Detail) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Mar. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]      
Warrant liability $ 180 $ 232 $ 1,105
Maximum maturity period of cash and cash equivalents 90 days 90 days  
Maximum maturity period of short-term investments 1 year 1 year  
Series A and Series B Warrants issued in July 2014 Financing [Member]      
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]      
Warrants outstanding and exercisable 0 0  
Maximum [Member]      
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]      
Maturity period of securities 1 year 1 year