Summary of Significant Accounting Policies - Properties in Development (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property Plant And Equipment [Line Items]
Total real estate assets	$ 11,095,294	$ 10,863,162
Other Cost and Expense, Operating	2,500	1,900	$ 1,500
Refundable deposits - development
Property Plant And Equipment [Line Items]
Nonrefundable deposits and other predevelopment costs	17,700	10,600
Parent Company [Member]
Property Plant And Equipment [Line Items]
Land	4,288,695	4,205,445
Land improvements	607,624	613,847
Buildings	5,101,061	5,088,102
Building and tenant improvements	946,034	901,596
Construction in progress	151,880	54,172
Total real estate assets	$ 11,095,294	$ 10,863,162