v2.4.0.6
Equity and Earnings Per Share Diluted Table (Detail) (USD $)
In Thousands, except Share data, unless otherwise specified
3 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Diluted earnings per share:    
Net income available for common stockholders $ 6,557 $ 12,323
Weighted average shares of common stock outstanding:    
Weighted Average Number of Shares Outstanding, Basic 47,499,898 45,576,925
Potentially dilutive common shares:    
Issuable pursuant to 2007 ROI Unit Stock Plan 188,416 374,539
Weighted Average Number of Shares Outstanding, Diluted 47,688,314 45,951,464
Earnings Per Share, Diluted $ 0.14 $ 0.27
Common Class A
   
Weighted average shares of common stock outstanding:    
Weighted Average Number of Shares Outstanding, Basic 47,499,798 45,576,825
Common Class B
   
Weighted average shares of common stock outstanding:    
Weighted Average Number of Shares Outstanding, Basic 100 100