v3.21.2

Non-Controlling Interests - Additional Information (Details) - shares shares in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2021
Noncontrolling Interest [Abstract] |  |
Number of OP units issued during period | 1,611 | 1,859

X
- Definition Number of OP units issued during period. + References No definition available. + Details
Name: | bnl_NumberOfOpUnitsIssuedDuringPeriod
Namespace Prefix: | bnl_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

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