Real Estate Assets, Discontinued Operations and Assets Held for Sale (Allocation of Shareholders' Income (Loss) Between Continuing and Discontinued Operations) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Discontinued Operations
Income from continuing operations attributable to common shareholders	$ 175,817	$ 39,797	$ 255,179	$ 59,206
Income from discontinued operations attributable to common shareholders	0	23	0	70
Net income attributable to common shareholders	$ 175,817	$ 39,820	$ 255,179	$ 59,276