Consolidated Quarterly Financial Data - Schedule of Consolidated Quarterly Financial Data (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 12 Months Ended
Dec. 08, 2017
Sep. 15, 2017
Jun. 15, 2017
Mar. 15, 2017
Dec. 15, 2016
Sep. 15, 2016
Jun. 15, 2016
Mar. 15, 2016
Dec. 31, 2017
Sep. 30, 2017
Jun. 30, 2017
Mar. 31, 2017
Dec. 31, 2016
Sep. 30, 2016
Jun. 30, 2016
Mar. 31, 2016
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]                                      
Total revenues                 $ 107,370 $ 108,721 $ 108,670 $ 106,497 $ 109,781 $ 109,541 $ 110,008 $ 106,010 $ 431,258 $ 435,340 $ 402,706
Depreciation and amortization                 43,052 43,318 43,441 43,875 43,534 43,820 42,759 42,923 173,686 173,036 166,478
Interest                 27,589 29,948 28,051 27,806 27,887 28,662 29,676 32,465 113,394 118,690 139,183
Other expenses                 19,515 40,514 40,329 46,669 52,317 35,741 31,379 26,767 147,027 146,204  
(Loss) gain on debt extinguishment                 (1,190) 1,792 7 (30) (77) (8,016) 14,777 (5,079) 579 1,605 (2,375)
Gain on disposition of assets                 20,712 10,089 6,884 5,013 8,397 11,517 5,635 4,074 42,698 29,623  
(Loss) income from continuing operations                 36,736 6,822 3,740 (6,870) (5,637) 4,819 26,606 2,850 40,428 28,638 (32,701)
Income (loss) from discontinued operations                 (945) (1,500) 19,466 19,699 6,625 22,580 19,353 20,250 36,720 68,808 125,913
Dividends paid to preferred stockholders                 2,530 0 0 0         2,530 0 0
Net income attributable to common stockholders/ after preferred distributions                 $ 33,261 $ 5,322 $ 23,206 $ 12,829 $ 988 $ 27,399 $ 45,959 $ 23,100 $ 74,618 $ 97,446 $ 93,212
Net income per share attributable to common stockholders and partners:                                      
Basic (in dollars per share)                 $ 0.07 $ 0.01 $ 0.05 $ 0.03 $ 0.00 $ 0.06 $ 0.10 $ 0.05 $ 0.16 $ 0.21 $ 0.21
Diluted (in dollars per share)                 0.07 0.01 0.05 0.03 0.00 0.06 0.10 0.05 0.16 0.21 $ 0.21
Dividends declared per common share and partnership unit (in dollars per share) $ 0.18 $ 0.18 $ 0.18 $ 0.18 $ 0.18 $ 0.175 $ 0.175 $ 0.175 $ 0.18000 $ 0.18000 $ 0.18000 $ 0.18000 $ 0.18000 $ 0.175 $ 0.175 $ 0.175 $ 0.72 $ 0.705