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Summary of Significant Accounting Policies - Construction in Progress (Textual) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Construction in Progress [Line Items] |  |  |
Internal direct construction costs capitalized related to development of properties and land holdings | $ 7.3 | $ 5.2 | $ 3.7
Development [Member] |  |  |
Construction in Progress [Line Items] |  |  |
Capitalized interest | $ 10.2 | $ 4.8 | $ 2.6

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- Definition Amount of interest capitalized during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Allowance for Funds Used during Construction -URI http://asc.fasb.org/extlink&oid=6504829 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391 + Details
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