Quarterly report pursuant to Section 13 or 15(d)

Equity and Share-Based Compensation - Additional Information (Detail)

v3.7.0.1
Equity and Share-Based Compensation - Additional Information (Detail) - USD ($)
3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock compensation expense $ 413,000 $ 140,000
Option exercises during period 0  
2009 Long-Term Incentive Plan [Member] | Class A Common Stock [Member] | Independent Directors Compensation Plan [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Issuance of shares for compensation 704