Income Taxes (Details) (USD $)
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Income Tax Disclosure [Abstract]    
Income before income tax $ 58,151,000 $ 146,603,000
Provision for income taxes 28,506,000 38,015,000
Effective tax rate 49.00% 25.90%
Change in unrecognized tax benefits for the period 8,100,000  
Unrecognized tax benefits approximate amount of estimated reduction within the next twelve months $ 11,000,000