v3.8.0.1

Assets Held for Sale or Contribution - Summary of Assets Held for Sale or Contribution (Detail) ft² in Thousands, $ in Thousands | Sep. 30, 2017 USD ($) ft² Property | Dec. 31, 2016 USD ($) ft² Property
--- | --- | ---
Long Lived Assets Held For Sale [Line Items] |  |
Total assets held for sale or contribution | $ 321,905 | $ 322,139
Total liabilities associated with assets held for sale or contribution – included in Other Liabilities | $ 7,389 | $ 4,984
Disposal Group Heldforsale Not Discontinued Operations |  |
Long Lived Assets Held For Sale [Line Items] |  |
Number of operating properties | Property | 26 | 13
Square feet | ft² | 4,952 | 4,167

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- Definition Amount classified as assets attributable to disposal group held for sale or disposed of. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=84176398&loc=d3e2941-110230 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=65878427&loc=d3e1107-107759 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5B -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721673-107760 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=65878427&loc=SL51721533-107759 + Details
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