Accounts Receivable, Net (Schedule Of Accounts Receivable) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012		Dec. 31, 2011
Straight-line rent receivable	$ 27,064		$ 26,499
Deferred rent receivable	4,420	[1]	4,420	[1]
Allowance for doubtful accounts	(4,746)		(5,152)
Total	35,602		35,005
Rent deferral payments interest rate	8.70%
Tenants [Member]
Carrying amounts of accounts receivable	6,794		6,874
Non-Tenants [Member]
Carrying amounts of accounts receivable	752		1,265
Canada Revenue Agency [Member]
Carrying amounts of accounts receivable	1,318		1,099
Private Equity Firm Guarantor [Member]
Deferred rent receivable	3,400
Other Guarantor [Member]
Deferred rent receivable	$ 1,000		$ 1,000

[1] Rent deferral payments of $3.4 million are guaranteed by a private equity firm. The unguaranteed rent deferral of $1.0 million has been fully reserved at March 31, 2012 and December 31, 2011. Rent deferral payments are due on or before December 31, 2018 and bear interest at 8.7%.