Earnings Per Share (Reconciliation) (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Earnings Per Share, Basic [Abstract]    
Net income $ 61,022 $ 71,655
Net income attributable to non-controlling interests 0 (76)
Non-forfeitable dividends on unvested restricted shares (56) (10)
Net income attributable to the Company’s common stockholders for basic earnings per share $ 60,966 $ 71,569
Weighted average number shares outstanding – basic (in shares) 304,158 304,569
Net income (usd per share) $ 0.20 $ 0.23
Computation of Diluted Earnings Per Share:    
Net income attributable to the Company’s common stockholders for diluted earnings per share $ 60,966 $ 71,569
Equity awards (in shares) 120 226
Weighted average shares outstanding - diluted (in shares) 304,278 304,795
Net income (usd per share) $ 0.20 $ 0.23