v3.20.2

COVID-19 Pandemic - Additional Information (Detail) - COVID-19 Pandemic | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 2020 Tenant
Unusual Or Infrequent Item [Line Items] |  |
Number of tenants received rent relief |  | 15
Rent relief granted as percentage of annualized contractual revenues | 9.70% | 9.70%
Number of tenants granted relief as partial deferral |  | 1
Period of partial abatement of rent |  | 9 months
Lease term extension on partial abatement of rent |  | 3 years
Partial rent deferrals percentage of rent revenues | 3.00% |
Abatement rent percentage of rent revenues | 1.10% |
Weighted average deferral period |  | 3 months 12 days
Weighted average payback period |  | 5 months 18 days
Minimum |  |
Unusual Or Infrequent Item [Line Items] |  |
Partial rent deferral period |  | 2 months
Repayment period |  | 3 months
Maximum |  |
Unusual Or Infrequent Item [Line Items] |  |
Partial rent deferral period |  | 6 months
Repayment period |  | 1 year

X
- Definition Abatement rent percentage of rent revenues. + References No definition available. + Details
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Namespace Prefix: | ck1424182_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

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- Definition Lease term extension on partial abatement of rent. + References No definition available. + Details
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Namespace Prefix: | ck1424182_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition Number of tenants granted relief as partial deferral. + References No definition available. + Details
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Namespace Prefix: | ck1424182_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

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- Definition Number of tenants received rent relief. + References No definition available. + Details
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Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

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- Definition Partial rent deferral period. + References No definition available. + Details
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Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition Partial rent deferrals percentage of rent revenues. + References No definition available. + Details
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Balance Type: | na
Period Type: | duration

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- Definition Period of partial abatement of rent. + References No definition available. + Details
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Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition Rent relief granted as percentage of annualized contractual revenues. + References No definition available. + Details
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Namespace Prefix: | ck1424182_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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- Definition Repayment period. + References No definition available. + Details
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Namespace Prefix: | ck1424182_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition Weighted average deferral period. + References No definition available. + Details
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Namespace Prefix: | ck1424182_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition Weighted average payback period. + References No definition available. + Details
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Namespace Prefix: | ck1424182_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- 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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- Details
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- Details
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