Schedule II-Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Tenant and other receivables—allowance
Changes in valuation allowance
Balance at Beginning of Year	$ 17,325	$ 14,341	$ 11,326
Additions Charged Against Operations	13,533	13,425	17,232
Uncollectible Accounts Written-off/Recovery	(12,790)	(10,441)	(14,217)
Balance at End of Year	18,068	17,325	14,341
Deferred rent receivable—allowance
Changes in valuation allowance
Balance at Beginning of Year	30,333	29,580	29,156
Additions Charged Against Operations	4,140	7,563	7,153
Uncollectible Accounts Written-off/Recovery	(7,062)	(6,810)	(6,729)
Balance at End of Year	$ 27,411	$ 30,333	$ 29,580

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Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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- Definition

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