Equity Incentive Plan - Equity Non-cash Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
General and Administrative Expenses
Equity Incentive Plan
Share-based compensation	$ 2,946	$ 2,556	$ 8,736	$ 7,371
Restricted stock | General and Administrative Expenses
Equity Incentive Plan
Share-based compensation	487	447	1,435	1,318
LTIP Units | General and Administrative Expenses
Equity Incentive Plan
Share-based compensation	981	901	2,923	2,687
Performance shares | General and Administrative Expenses
Equity Incentive Plan
Share-based compensation	1,356	1,107	4,004	3,062
Independent Director | General and Administrative Expenses
Equity Incentive Plan
Share-based compensation	$ 122	$ 101	$ 374	$ 304
Common Stock | Independent Director
Equity Incentive Plan
Number of days of average trailing stock price used to calculate number of shares of common stock granted	10 days	10 days	10 days	10 days