Quarterly report pursuant to Section 13 or 15(d)

Mandatorily Redeemable Preferred Stock - Additional Information (Detail)

v3.5.0.2
Mandatorily Redeemable Preferred Stock - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
 1 Months Ended 3 Months Ended 9 Months Ended
Feb. 29, 2012
Sep. 30, 2016
Sep. 30, 2016
Dec. 31, 2015
Class of Stock [Line Items]        
Write-off of deferred offering costs   $ 60 $ 200  
Mandatorily Redeemable Preferred Stock [Member]        
Class of Stock [Line Items]        
Redeemable preferred stock, shares issued (in shares) 1,540,000      
Redeemable preferred stock, par value (in dollars per share) $ 0.001      
Public offering price $ 25.00      
Gross proceeds of the offering $ 38,500      
Net proceeds, after deducting offering expenses $ 36,700      
Series C Preferred Stock [Member]        
Class of Stock [Line Items]        
Redeemable preferred stock, dividend rate percentage 7.125%      
Series C Preferred Stock [Member] | Mandatorily Redeemable Preferred Stock [Member]        
Class of Stock [Line Items]        
Redeemable preferred stock, shares issued (in shares)   0 0 1,540,000
Redeemable preferred stock, par value (in dollars per share)   $ 0.001 $ 0.001 $ 0.001