Unaudited Pro Forma Financial Information (Detail) (USD $)
In Thousands, except Per Share data, unless otherwise specified
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Business Acquisition    
Revenue $ 360,837 $ 362,355
Revenue in excess of operating expenses 215,273 218,815
Net income (loss) $ (111,243) $ 30,381
Basic net income (loss) per share $ (1.63) $ 0.51
Diluted net income (loss) per share $ (1.63) $ 0.51