v3.8.0.1

Sale of Real Estate (Tables) | 12 Months Ended
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Dec. 31, 2017
Real Estate [Abstract] |
Schedule Of Sale Of Real Estate Text Block | The Company closed on the following sales of real estate, none of which qualified as discontinued operations, during the years ended December 31, 2017, 2016, and 2015.
|  | For the years ended December 31, |
(in thousands, except number of properties) |  | 2017 |  |  | 2016 |  |  | 2015 |
Number of properties disposed |  |  | 13 |  |  |  | 9 |  |  | 6 |
Aggregate sale price |  | $ | 66,532 |  |  | $ | 39,500 |  |  | $ | 19,455 |
Aggregate carrying value |  |  | 50,339 |  |  |  | 32,665 |  |  |  | 18,672 |
Additional sales expenses |  |  | 3,201 |  |  |  | 910 |  |  |  | 1,496 |
Gain (loss) on sale of real estate |  |  | 12,992 |  |  |  | 5,925 |  |  |  | (713 | )

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- Definition Schedule of sale of real estate. + References No definition available. + Details
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Namespace Prefix: | ck0001424182_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

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- References No definition available. + Details
Name: | us-gaap_RealEstateAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration