Stockholders' Equity - Share Repurchase Programs - Additional Information (Details) (USD $)
In Millions, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Jul. 31, 2014
Equity [Abstract]    
Purchase of common stock, shares 2.9  
Purchase of common stock, value $ 40.0  
Shares repurchase authorized amount   200.0
Share repurchase plan, remaining authorized amount $ 110.0