v3.22.2.2

Equity - Summary of Common Shares under Company's ATM Program (Details) - ATM - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2022 | Sep. 30, 2022
Equity [Line Items] |  |
Number of common shares issued | 962 | 10,471
Weighted average sale price per share | $ 21.44 | $ 21.66
Net proceeds | $ 20,248 | $ 222,895
Gross proceeds | $ 20,626 | $ 226,483

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

X
- Definition Gross proceeds from sales + References No definition available. + Details
Name: | bnl_GrossProceedsFromSales
Namespace Prefix: | bnl_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Weighted average sale price per share + References No definition available. + Details
Name: | bnl_WeightedAverageSalePricePerShare
Namespace Prefix: | bnl_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromIssuanceOrSaleOfEquity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The number of shares issued or sold by the subsidiary or equity method investee per stock transaction. + References No definition available. + Details
Name: | us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_SubsidiarySaleOfStockAxis=bnl_AtmMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |