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Real Estate and Intangible Assets - Schedule of Revenue and Earnings Recognized on Properties Acquired (Detail) - Asset Acquisitions [Member] $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) acquisition	Dec. 31, 2015 USD ($) acquisition	Dec. 31, 2014 USD ($) acquisition
Business Acquisition [Line Items]
Number Of Acquisitions Completed | acquisition	2	6	11
Rental Revenue	$ 1,462	$ 4,919	$ 5,605
Earnings	$ (162)	$ (63)	$ 36

X

- Definition

Net income loss from acquired properties.

+ References

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+ Details

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- Definition

Number of acquisitions completed.

+ References

No definition available.

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X

- Definition

Operating leases income statement lease revenue from acquired properties.

+ References

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X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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