Consolidated Statements of Equity (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012
Issuance of shares, offering costs	$ 6,746	$ 0
Common shares, dividend declared per share	$ 0.42	$ 0.375
LTIP units, distributions per unit	$ 0.42	$ 0.375

Direct costs (e.g., legal and accounting fees) associated with issuing stock that is deducted from additional paid in capital. Also includes any direct costs associated with stock issues under a shelf registration.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Technical Practice Aid (TPA)

-Number 4110

-Paragraph 1, 10

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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