v3.24.3

Significant Accounting Policies - Summary of Impairment Charge (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024 USD ($) Property	Sep. 30, 2023 USD ($) Property	Sep. 30, 2024 USD ($) Property	Sep. 30, 2023 USD ($) Property
Impaired Long-Lived Assets Held and Used [Line Items]
Number of properties | Property	3	0	17	1
Impairment charge | $	$ 1,059	$ 0	$ 31,311	$ 1,473

X

- Definition

The number of individual properties owned.

+ References

No definition available.

+ Details

Name:	bnl_NumberOfIndividualProperties
Namespace Prefix:	bnl_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

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

X

- Definition

The charge against earnings in the period to reduce the carrying amount of real property to fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482099/360-10-50-2

+ Details

Name:	us-gaap_ImpairmentOfRealEstate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration