Consolidated Statements of Cash Flows - Supplemental Information Supplemental Cash Flows Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Supplemental Cash Flow Elements [Abstract]
Interest paid, net of amounts capitalized	$ 62,641	$ 38,062	$ 43,166
Income taxes paid	343	0	0
Non-Cash Transactions:
Transfer from projects under development to operating properties	443,932	0	325,490
Common stock dividends declared and accrued	44,681	42,559	27,326
Change in accrued property acquisition, development, and tenant asset expenditures	(25,745)	4,891	(18,104)
Transfer from land held and other assets to projects under development	22,771	0	0
Non-cash assets and liabilities assumed in TIER transaction	0	1,512,373	0
Transfer from operating properties and related liabilities to assets and liabilities of real estate assets held for sale	188,378	318,516	0
Ground lease right-of-use assets and associated liabilities	0	56,294	0
Transfer from investment in unconsolidated joint ventures to operating properties	0	50,781	0
Non-cash consideration for property acquisition	0	10,071	0
Cumulative effect of change in accounting principle	0	0	22,329
Transfer from investment in unconsolidated joint ventures to projects under development	$ 0	$ 0	$ 7,025