Quarterly report pursuant to Section 13 or 15(d)

Equity-Based Compensation - Additional Information (Detail)

v3.19.1
Equity-Based Compensation - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
1 Months Ended 3 Months Ended 12 Months Ended
Oct. 31, 2018
May 31, 2016
Aug. 31, 2015
Mar. 31, 2019
Mar. 31, 2018
Dec. 31, 2018
Nov. 02, 2012
Non-Qualified Stock Options              
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]              
Restricted stock units granted 105,398            
Restricted stock units\non-qualified stock options, granted description One third of the NQOs will vest and become exercisable on each of the first, second and third anniversaries of the grant date.            
Fair value assumptions, strike price $ 13.97            
Fair value assumptions, risk free rate 2.94%            
Fair value assumptions, expiration 5 years            
Fair value assumptions, volatility 32.70%            
Compensation expense forfeiture rate 1.00%            
Compensation expense       $ 842 $ 800    
Unrecognized compensation expense related to unvested awards       $ 1,550   $ 2,392  
Recognition period of unrecognized compensation expense related to unvested awards       1 year 3 months 3 days   1 year 6 months 3 days  
Restricted Stock Units              
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]              
Compensation expense       $ 842 $ 800    
Unrecognized compensation expense related to unvested awards       $ 1,550   $ 2,392  
Recognition period of unrecognized compensation expense related to unvested awards       1 year 3 months 3 days   1 year 6 months 3 days  
2012 Equity Incentive Plan              
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]              
Shares reserved for issuance       584,679      
Shares reserved for issuance, authorized             1,687,500
Restricted stock units granted   3,791 966,510        
Fair Value per unit   $ 13.19 $ 13.23        
Restricted stock units\non-qualified stock options, granted description       Twenty-five percent of the RSUs granted vest and settle on each of the first, second, third and fourth anniversaries of the grant date.      
2012 Equity Incentive Plan | Employee              
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]              
Restricted stock units granted   7,582          
Fair Value per unit   $ 13.19          
Restricted stock units\non-qualified stock options, granted description       Twenty-five percent of the RSUs granted vest and settle on each of the first, second, third and fourth anniversaries of the grant date.      
2012 Equity Incentive Plan | Board of Directors              
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]              
Restricted stock units granted   3,000          
Fair Value per unit   $ 13.19          
Restricted stock units\non-qualified stock options, granted description       One hundred percent of the RSUs granted vested and settled on the first anniversary of the grant date.      
2012 Equity Incentive Plan | First Anniversary              
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]              
Restricted stock, vesting percentage   25.00% 25.00%        
2012 Equity Incentive Plan | First Anniversary | Employee              
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]              
Restricted stock, vesting percentage   25.00%          
2012 Equity Incentive Plan | First Anniversary | Board of Directors              
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]              
Restricted stock, vesting percentage   100.00%          
2012 Equity Incentive Plan | Second Anniversary              
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]              
Restricted stock, vesting percentage   25.00% 25.00%        
2012 Equity Incentive Plan | Second Anniversary | Employee              
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]              
Restricted stock, vesting percentage   25.00%          
2012 Equity Incentive Plan | Third Anniversary              
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]              
Restricted stock, vesting percentage   25.00% 25.00%        
2012 Equity Incentive Plan | Third Anniversary | Employee              
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]              
Restricted stock, vesting percentage   25.00%          
2012 Equity Incentive Plan | Fourth Anniversary              
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]              
Restricted stock, vesting percentage   25.00% 25.00%        
2012 Equity Incentive Plan | Fourth Anniversary | Employee              
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]              
Restricted stock, vesting percentage   25.00%