Investments In Joint Ventures (Narrative) (Details)	12 Months Ended
	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)		Apr. 12, 2018
Direct Costs of Leased and Rented Property or Equipment	$ 220,732,000	$ 217,817,000	$ 206,780,000
Income (Loss) from Equity Method Investments, Net of Dividends or Distributions	$ 7,836,000	$ 6,822,000	$ 7,125,000	[1],[2]
Number of joint ventures accounted for under equity method investments	3	3	3
Maximum guaranteed amount of loans utilized for construction and development activities for joint ventures	$ 0
Fees earned for property and asset management, construction, development, and other services to joint ventures	5,700,000	$ 5,800,000	$ 5,300,000
Maximum Investments by Formed Unconsolidated Joint Venture	$ 450,000,000
Number of Units in Real Estate Property					360
Minimum [Member]
Equity method investment ownership percentage	20.00%
Maximum [Member]
Equity method investment ownership percentage	31.30%
Hurricane [Member]
Income (Loss) from Equity Method Investments, Net of Dividends or Distributions	$ 400,000
Non-consolidated entity [Member] | Hurricane [Member]
Direct Costs of Leased and Rented Property or Equipment	$ 1,300,000

[1] Equity in income excludes our ownership interest of fee income from various services provided by us to the Funds

[2] Equity in income for the years ended December 31, 2017 includes our ownership interest of the hurricane related recoveries and expenses of approximately $0.4 million, respectively.