Summary of Significant Accounting Policies Narratives (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2019
Deferred Costs, Leasing, Net		$ 6,500,000	$ 2,900,000
Operating Lease, Weighted Average Discount Rate, Percent	5.40%
Operating right-of-use assets, net (1)	$ 19,865,000	0		$ 35,300,000
Ground lease deferred rent payable	0	3,510,000		3,500,000
Other identified intangible assets, net	48,620,000	55,469,000		767,000
Prepaid expenses	$ 12,556,000	$ 6,482,000		$ 140,000
Operating Lease, Weighted Average Remaining Lease Term	23 years 10 months 24 days
Fixed Operating and Finance Lease, Cost	$ 2,300,000
Variable operating lease costs	$ 1,300,000