Discontinued Operations (Schedule Of Income From Discontinued Operations) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	1 Months Ended	3 Months Ended								12 Months Ended													1 Months Ended	12 Months Ended
	Feb. 28, 2009	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008	Dec. 31, 2011 Segment, Discontinued Operations [Member]	Dec. 31, 2010 Segment, Discontinued Operations [Member]	Dec. 31, 2009 Segment, Discontinued Operations [Member]	Dec. 31, 2010 Facility Operating Expense [Member]	Dec. 31, 2009 Facility Operating Expense [Member]	Dec. 31, 2011 Operating Income [Member]	Dec. 31, 2010 Operating Income [Member]	Dec. 31, 2009 Operating Income [Member]	Dec. 31, 2009 Non-Operating Income [Member]	Jan. 31, 2009 Non-Operating Income [Member] Settlement of a terminated lease [Member]	Dec. 31, 2009 Non-Operating Income [Member] Cancellation of liabilities [Member]
Revenues:
Revenues										$ 5,063	$ 5,847	$ 6,428
Expenses:
Depreciation										11,992	11,203	8,621		39	284	1,345
Disposal Group, Including Discontinued Operation, Operating Expense										39	270	1,396					(14)	26
Impairment of real estate assets in discontinued operations	25											25	1,986
Income from operations - discontinued										5,024	5,577	7,168							5,024	5,577	5,032	2,136	642	1,493
Gain loss on sale of properties net of applicable income Taxes										3,348	2,004
Income from discontinued operations		$ 1,210	$ 2,283	$ 1,276	$ 3,603	$ 1,371	$ 1,371	$ 3,321	$ 1,519	$ 8,372	$ 7,581	$ 7,168
Weighted average common shares outstanding:
Basic		27,741,961	27,729,560	27,708,136	27,696,727	27,686,217	27,673,703	27,665,629	27,632,376	27,719,096	27,664,482	27,586,338
Diluted		27,784,915	27,789,725	27,799,616	27,796,109	27,783,517	27,737,802	27,729,034	27,681,479	27,792,592	27,732,959	27,618,300
Earnings Per Share, Basic and Diluted [Abstract]
Income Loss From Discontinued Operations Net Of Tax Per Basic Share		$ 0.04	$ 0.08	$ 0.05	$ 0.13	$ 0.05	$ 0.05	$ 0.12	$ 0.06	$ 0.30	$ 0.27	$ 0.26
Income loss from discontinued operations net of tax per diluted share		$ 0.04	$ 0.08	$ 0.05	$ 0.13	$ 0.05	$ 0.05	$ 0.12	$ 0.06	$ 0.30	$ 0.27	$ 0.26