Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Additional Information (Detail)

v2.4.0.8
Stockholders' Equity - Additional Information (Detail)
3 Months Ended 9 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Sep. 30, 2014
Sep. 30, 2013
Class B Common Stock [Member]
       
Class of Stock [Line Items]        
Certain Class B stockholders converted into Class A 0 88,160 299,776 104,396
Class A Common Stock [Member]
       
Class of Stock [Line Items]        
Shares issued as a part of conversion 0 88,160 299,776 104,396