v3.19.3.a.u2

Summary of Significant Accounting Policies - Additional Information (Detail) | 12 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Dec. 31, 2019 USD ($) Lease | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Sep. 30, 2019 | Mar. 31, 2019 | Jan. 01, 2019 USD ($) | Sep. 30, 2018 | Sep. 30, 2017
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Impairment of real estate assets | $ 3,452,000 | $ 2,061,000 | $ 2,608,000 |  |  |  |  |
Weighted average price per square foot | $ 226,000 |  |  |  |  |  |  |
Sale of real estate description | Company recognized real estate sales when all of the following criteria were met: (i) a sale was consummated, (ii) the buyer had demonstrated an adequate commitment to pay for the property, (iii) the Company’s receivable was not subject to future subordination, and (iv) the Company had transferred the risks and rewards of ownership to the buyer and did not have continuing involvement. |  |  |  |  |  |  |
Lessor operating lease description | A lease arrangement was classified as an operating lease if none of the following criteria were met: (i) ownership transferred to the lessee prior to or shortly after the end of the lease term, (ii) the lessee had a bargain purchase option during or at the end of the lease term, (iii) the lease term was greater than or equal to 75% of the underlying property’s estimated useful life, or (iv) the present value of the future minimum lease payments (excluding executory costs) was greater than or equal to 90% of the fair value of the leased property. If one or more of these criteria were met, and the minimum lease payments were determined to be reasonably predictable and collectible, the lease arrangement was generally accounted for as a direct financing lease. Consistent with ASC 840, Leases, if the fair value of the land component was 25% or more of the total fair value of the leased property, the land was considered separately from the building for purposes of applying the lease term and minimum lease payments criterion in (iii) and (iv) above |  |  |  |  |  |  |
Lease term as percentage of property's useful life | 75.00% |  |  |  |  |  |  |
Present value of future minimum lease payments as percentage of fair value of leased property | 90.00% |  |  |  |  |  |  |
Fair value of land component as percentage of leased property | 25.00% |  |  |  |  |  |  |
Obligation to fund capital improvements | $ 0 |  |  |  |  |  |  |
Percentage of income tax benefit likely of being realized upon settlement | more than 50% |  |  |  |  |  |  |
Uncertain tax positions | $ 0 | 0 | 0 |  |  |  |  |
Lease liabilities | 1,209,000 |  |  |  |  |  |  |
Accounted for using the direct financing method | 41,890,000 | 42,000,000 |  |  |  |  |  |
Income taxes | 2,415,000 | 857,000 | 624,000 |  |  |  |  |
Other Nonoperating Income (Expenses) |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Income taxes |  | 857,000 | $ 624,000 |  |  |  |  |
Prepaid Expenses And Other Assets |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Right-of-use assets | 1,614,000 |  |  |  |  |  |  |
Restricted cash |  | 377,000 |  |  |  |  |  |
Tenant and capital reserves |  | 1,136,000 |  |  |  |  |  |
Accounts Payable And Other Liabilities |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Lease liabilities | 1,209,000 |  |  |  |  |  |  |
Tenant improvement allowances | 2,706,000 | $ 2,125,000 |  |  |  |  |  |
ASU 2018-11 |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Right-of-use assets |  |  |  |  |  | $ 1,687,000 |  |
Lease liabilities |  |  |  |  |  | 1,261,000 |  |
Rent liability |  |  |  |  |  | 7,000 |  |
Ground lease |  |  |  |  |  | $ 432,000 |  |
ASU 2016-13 |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Accounted for using the direct financing method | $ 41,890,000 |  |  |  |  |  |  |
Percentage of total assets for investment in direct financing leases | 1.10% |  |  |  |  |  |  |
Number of individual leases | Lease | 16 |  |  |  |  |  |  |
Broadstone Net Lease, LLC |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Percentage of shares owned by, non-controlling interest | 6.30% | 7.30% | 7.60% |  |  |  |  |
IPO |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Deferred offering costs | $ 668,000 |  |  |  |  |  |  |
Capitalization Rate |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Impaired assets at fair value assumptions used to estimate fair value |  |  |  | 14.58% | 14.58% |  |  |
Minimum |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Lease term | 9 years |  |  |  |  |  |  |
Minimum | Capitalization Rate |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Impaired assets at fair value assumptions used to estimate fair value |  |  |  |  |  |  | 7.50% | 7.25%
Maximum |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Lease term | 29 years |  |  |  |  |  |  |
Maximum | Capitalization Rate |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Impaired assets at fair value assumptions used to estimate fair value |  |  |  |  |  |  | 10.00% | 12.00%
Weighted Average | Discount Rate |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Impaired assets at fair value assumptions used to estimate fair value |  |  |  | 8.00% | 8.00% |  | 8.00% | 8.00%

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