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Stockholders' Equity - Equity and Securities Repurchase Programs (Details) - USD ($)
 1 Months Ended 12 Months Ended
Jun. 30, 2015
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Equity, Class of Treasury Stock [Line Items]          
Proceeds from common stock offering, net of issuance costs $ 373,000,000 $ 0 $ 373,000,000 $ 0  
Number of warrants issued (in shares)         13,490,236
Striking price of Warrants (USD per share)         $ 53.8475
Trading days measurement period (in days)   160 days      
Stated interest rate for Warrants   1.125%      
Threshold percentage of stock price trigger   0.625%      
Common Stock          
Equity, Class of Treasury Stock [Line Items]          
Shares issued in public offering (in shares) 5,750,000        
Offering price (USD per share) $ 64.90        
Common Stock | December 2015 Repurchase Program          
Equity, Class of Treasury Stock [Line Items]          
Approved amount related to stock repurchase program     $ 50,000,000