Income Per Share and Partnership Unit - Schedule of Reconciliation of the Numerator and Denominator Used in the Computation of Basic and Diluted Income Per Share (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Basic and diluted income:    
Income from continuing operations $ 43,578 $ 38,078
Less: income attributable to unvested restricted stock (272) (383)
Less: dividends paid to preferred stockholders (2,588) (2,588)
Income used in basic and diluted income per share from continuing operations 40,718 35,107
Loss used in basic and diluted loss per share from discontinued operations 0 (7,360)
Net income attributable to common stockholders used in basic and diluted income per share $ 40,718 $ 27,747
Basic weighted average shares of common stock outstanding:    
Weighted average shares of common stock outstanding 85,916,656 89,296,899
Less: Unvested weighted average shares of restricted stock (419,563) (321,508)
Weighted average shares of common stock outstanding used in basic income per share 85,497,093 88,975,391
Net income per share attributable to common stockholders - basic:    
Continuing operations (in USD per share) $ 0.48 $ 0.39
Discontinued operations (in USD per share) 0.00 (0.08)
Net income per share attributable to common stockholders - basic (in USD per share) $ 0.48 $ 0.31
Dilutive weighted average shares of common stock outstanding:    
Weighted average shares of common stock outstanding used in diluted income per share 85,504,897 89,020,751
Net income per share attributable to common stockholders - diluted    
Continuing operations (in USD per share) $ 0.48 $ 0.39
Discontinued operations (in USD per share) 0.00 (0.08)
Net income per share attributable to common stockholders - diluted (in USD per share) $ 0.48 $ 0.31
Unvested shares of restricted stock, less shares assumed repurchased at market    
Potentially dilutive shares of common stock    
Potentially dilutive shares 132,744 50,464
Unvested market-based awards    
Dilutive weighted average shares of common stock outstanding:    
Unvested market-based awards/stock options (in shares) 7,804 45,360