v3.19.3.a.u2

Acquisitions - Purchase Price Allocation for Acquisitions (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Direct financing investments		$ 430	$ 3,546
Mortgages payable	$ (49,782)	(20,845)	(11,926)
Non-real estate liabilities		(56)	(2,777)
Business combination, recognized identifiable assets acquired and liabilities assumed, assets	999,730	598,567	681,289
Land
Business Acquisition [Line Items]
Business combination, recognized identifiable assets acquired and liabilities assumed, property, plant, and equipment	161,182	72,559	67,945
Land Improvements
Business Acquisition [Line Items]
Business combination, recognized identifiable assets acquired and liabilities assumed, property, plant, and equipment	47,391	32,498	54,804
Buildings and Improvements
Business Acquisition [Line Items]
Business combination, recognized identifiable assets acquired and liabilities assumed, property, plant, and equipment	772,998	454,391	508,541
Equipment
Business Acquisition [Line Items]
Business combination, recognized identifiable assets acquired and liabilities assumed, property, plant, and equipment		2,892	7,671
Acquired In-Place Leases
Business Acquisition [Line Items]
Business combination, recognized identifiable assets acquired and liabilities assumed, Intangible assets	80,952	62,631	77,073
Acquired Above-Market Leases
Business Acquisition [Line Items]
Business combination, recognized identifiable assets acquired and liabilities assumed, Intangible assets	2,800	5,538	14,905
Acquired Below-Market Leases
Business Acquisition [Line Items]
Business combination, recognized identifiable assets acquired and liabilities assumed, Intangible assets	$ (15,811)	$ (11,471)	$ (38,493)

X

- Definition

Business combination recognized identifiable assets acquired and liabilities assumed intangible liabilities.

+ References

No definition available.

+ Details

Name:	ck1424182_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleLiabilities
Namespace Prefix:	ck1424182_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Business combination recognized identifiable assets acquired and liabilities assumed mortgages payable.

+ References

No definition available.

+ Details

Name:	ck1424182_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedMortgagesPayable
Namespace Prefix:	ck1424182_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Business combination, recognized identifiable assets acquired and liabilities assumed, non-real estate liabilities

+ References

No definition available.

+ Details

Name:	ck1424182_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNonRealEstateLiabilities
Namespace Prefix:	ck1424182_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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

Name:	us-gaap_BusinessAcquisitionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of acquired direct financing lease receivable from business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472

+ Details

Name:	us-gaap_BusinessCombinationAcquiredDirectFinancingLeaseReceivable
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Amount of assets acquired at the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472

+ Details

Name:	us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=116868840&loc=d3e2207-128464

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472

+ Details

Name:	us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=116868840&loc=d3e2207-128464

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472

+ Details

Name:	us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_LandMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_LandImprovementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_BuildingImprovementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_EquipmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_LeasesAcquiredInPlaceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_AboveMarketLeasesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=ck1424182_BelowMarketLeasesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: