Quarterly report pursuant to Section 13 or 15(d)

Equity Share Repurchase Program (Details)

v3.8.0.1
Equity Share Repurchase Program (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Equity [Abstract]        
Number of shares authorized to be repurchased under stock repurchase program (in shares) 37,500,000   37,500,000  
Number of shares repurchased and retired to date (in shares) 12,067,500   12,067,500  
Cost of shares repurchased and retired to date $ 200,375   $ 200,375  
Repurchase of common stock (in shares) 0 0 0 (4,010,000)
Repurchase of common stock $ 0 $ 0 $ 0 $ (61,307)