Federal Income Tax Considerations (Schedule Of Deferred Tax Assets And Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012		Dec. 31, 2011
Deferred tax assets:
Impairment loss	$ 16,951	[1]	$ 20,450	[1]
Allowance on other assets	1,519		1,528
Interest expense	11,417		8,318
Net operating loss carryforward	8,642		4,870
Book-tax basis differential	1,148		1,132
Other	173		182
Total deferred tax assets	39,850		36,480
Valuation allowance	(28,376)	[2]	(24,595)	[2]
Total deferred tax assets, net of allowance	11,474		11,885
Deferred tax liabilities:
Straight-line rentals	977		1,612
Book-tax basis differential	2,339		3,553
Other	2		1
Total deferred tax liabilities	$ 3,318		$ 5,166

[1] Impairment losses will not be recognized until the related properties are sold and realization is dependent upon generating sufficient taxable income in the year the property is sold.

[2] Management believes it is more likely than not that a portion of the deferred tax assets, which primarily consists of impairment losses, interest expense and net operating losses, will not be realized and established a valuation allowance. However, the amount of the deferred tax asset considered realizable could be reduced if estimates of future taxable income are reduced.