Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Additional Information (Detail)

v3.2.0.727
Stockholders' Equity - Additional Information (Detail) - shares
3 Months Ended 6 Months Ended
Jun. 30, 2015
Jun. 30, 2014
Jun. 30, 2015
Jun. 30, 2014
Class B Common Stock [Member]        
Class of Stock [Line Items]        
Certain Class B stockholders converted into Class A 818,910 289,480 1,074,432 299,776
Class A Common Stock [Member]        
Class of Stock [Line Items]        
Shares issued as a part of conversion 818,910 289,480 1,074,432 299,776