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Real Estate and Intangible Assets - Schedule of Revenue and Earnings Recognized on Properties Acquired (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015
Business Acquisition [Line Items] |  |  |  |
Rental Revenue | $ 464 | $ 1,762 | $ 603 | $ 2,971
Earnings | (82) | (71) | (203) | $ 166
Richardson, TX [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Real estate acquisition costs |  |  | 100 |
Acquisition Date |  |  |  | Mar. 06, 2015
Rental Revenue |  | 656 |  | $ 1,496
Earnings |  | (57) |  | $ (22)
Birmingham, AL [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Real estate acquisition costs |  |  | 80 |
Acquisition Date |  |  |  | Mar. 20, 2015
Rental Revenue |  | 83 |  | $ 177
Earnings |  | (28) |  | $ 6
Columbus, OH [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Real estate acquisition costs |  |  | 70 |
Acquisition Date |  |  |  | May 28, 2015
Rental Revenue |  | 177 |  | $ 244
Earnings |  | (28) |  | $ 32
Salt Lake City UT [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Real estate acquisition costs |  |  | $ 100 |
Acquisition Date |  |  | May 26, 2016 | May 29, 2015
Rental Revenue | 358 | 572 | $ 497 | $ 780
Earnings | (22) | 14 | (143) | $ 122
Atlanta, GA [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Real estate acquisition costs | 100 |  | 100 |
Acquisition Date |  |  |  | Jul. 15, 2015
Rental Revenue |  | 274 |  | $ 274
Earnings |  | $ 28 |  | $ 28
Fort Lauderdale, FL [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Real estate acquisition costs | 70 |  | $ 70 |
Acquisition Date |  |  | Sep. 12, 2016 |
Rental Revenue | 106 |  | $ 106 |
Earnings | $ (60) |  | $ (60) |

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- Definition Operating leases income statement lease revenue from acquired properties. + References No definition available. + Details
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