Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
BASIC
Net income (loss) attributable to common shareholders	$ 21,721	$ (3,327)	$ 48,130	$ (19,284)
Weighted-average number of common shares outstanding - basic	232,635,137	237,312,726	232,587,083	237,690,306
Income (loss) per common share:
Net income (loss) attributable to common shares outstanding - basic (in dollars per share)	$ 0.09	$ (0.01)	$ 0.21	$ (0.08)
DILUTED
Impact of assumed conversions	$ 165	$ 0	$ 166	$ 0
Net income (loss) attributable to common shareholders	$ 21,886	$ (3,327)	$ 48,296	$ (19,284)
Effect of dilutive securities:
Unvested share-based payment awards (in shares)	129,810	0	91,637	0
OP Units (in shares)	3,534,931	0	3,542,610	0
Weighted-average common shares outstanding - diluted (in shares)	236,299,878	237,312,726	236,221,330	237,690,306
Net income (loss) attributable to common shareholders - per common share diluted (in dollars per share)	$ 0.09	$ (0.01)	$ 0.20	$ (0.08)

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