Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Net Income (Loss) Allocated to Common Stockholders [Abstract]
Net income from continuing operations	$ 23,163	$ 34,801	$ 57,395	$ 37,470
Net loss from discontinued operations	0	(881)	0	(1,454)
Net income	$ 23,163	$ 33,920	$ 57,395	$ 36,016
Weighted average shares outstanding, basic and diluted (in shares)	774,391,881	773,381,165	774,351,790	773,348,893
Income from continuing operations allocated to common shareholders per share (in dollars per share)	$ 0.03	$ 0.04	$ 0.07	$ 0.05
Income from discontinued operations allocated to common shareholders per share (in dollars per share)	0.00	0.00	0.00	0.00
Net income per common share, basic and diluted (in dollars per share)	$ 0.03	$ 0.04	$ 0.07	$ 0.05