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Equity Incentive Plan - 2020 Activity (Details) - USD ($) $ in Millions				9 Months Ended	12 Months Ended
	Feb. 13, 2020	Jan. 08, 2020	Jan. 07, 2019	Sep. 30, 2020	Dec. 31, 2019
LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted		136,741		278,806	364,173
Unrecognized compensation costs				$ 5.6
Unrecognized compensation costs, period for recognition				2 years 4 months 24 days
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	4 years	4 years
Stock Repurchased and Retired During Period, Shares				33,119	28,504
Granted				75,419	110,830
Unrecognized compensation costs				$ 3.7
Unrecognized compensation costs, period for recognition				2 years 6 months
Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs				$ 7.3
Unrecognized compensation costs, period for recognition				1 year 9 months 18 days
Performance Units Granted in 2017 [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)			1 year
Performance Units Granted in 2017 [Domain] \| LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of vested LTIP units and shares		76,096
Stock Repurchased and Retired During Period, Shares		18,241
Granted		65,969
Performance Units Granted in 2017 [Domain] \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of vested LTIP units and shares		46,376
Performance Units Granted in 2017 [Domain] \| Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted		3,398