Investment in Real Estate - Additional Information (Detail) $ in Thousands, ft² in Millions	9 Months Ended
Sep. 30, 2016 USD ($) ft² Property
Real Estate [Abstract]
Number of industrial properties acquired \| Property	4
Gross leasable area (GLA) of industrial properties acquired \| ft²	0.5
Purchase price of industrial properties acquired	$ 98,625
Number of industrial properties sold \| Property	50
Gross leasable area (GLA) of industrial properties sold \| ft²	2.6
Proceeds from sale of industrial properties	$ 138,970
Gain on sale of real estate	$ 60,828

Gross leasable area (GLA) of industrial properties acquired.

No definition available.

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- Definition

Gross leasable area (GLA) of industrial properties sold.

+ References

No definition available.

+ Details

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- Definition

Number of industrial properties sold.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

Amount of assets acquired at the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

+ Details

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Balance Type:	credit
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- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash inflow from sale of buildings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

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