Annual report pursuant to Section 13 and 15(d)

Equity - Class A Common Stock (Detail)

v3.7.0.1
Equity - Class A Common Stock (Detail) - Class A Common Stock - shares
1 Months Ended
Nov. 30, 2016
Aug. 31, 2016
Mar. 31, 2016
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Class Of Stock [Line Items]              
Common stock, shares outstanding       8,074,197 7,989,749 7,768,000 7,522,000
Issuance of Class A common Stock upon conversion of Class B units to Class A common stock 25,172 21,200 38,076        
Common stock conversion date Nov. 30, 2016 Aug. 31, 2016 Mar. 31, 2016