Real Estate Facilities (Narrative) (Details) (USD $)	6 Months Ended
	Jun. 30, 2011
Acquisition cost of real estate facilities	$ 23,300,000
Mortgage debt aggregate fair value	9,679,000
Acquisition Of Five Self Storage Facilities In Nevada And One In New York [Member]
Number of operating self storage facilities, Nevada	5
Number of operating self storage facilities, New York	1
Net rentable square feet	524,000
Acquisition cost of real estate facilities	44,040,000
Payments to acquire real estate	34,361,000
Mortgage debt aggregate fair value	9,679,000
Aggregate cost, real estate	46,026,000
Land lease intangible assets	4,738,000
Aggregate cost, intangibles	2,752,000
Two Expansion Projects [Member]
Newly developed facilities opened for operations	8,928,000
Proceeds from disposition of real estate facilities	400,000
Net loss with respect to disposition	125,000
Gain on disposed facilities	128,000
Loss on discontinued operations	$ 253,000