Summary of Significant Accounting Policies - Litigation and non-routine costs, net (Details) - USD ($) $ in Thousands, shares in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Litigation and non-routine costs, net:
Legal fees, costs and settlements	$ 4,819	$ 890,378	$ 293,531
Insurance recoveries	(2,471)	(48,420)	(2,568)
Other recoveries	0	(26,536)	0
Total	$ 2,348	$ 815,422	$ 290,963
Surrender of Limited Partner OP Units		2.9