v3.19.3.a.u2

Supplemental Cash Flow Disclosures - Additional Information (Detail) - USD ($) shares in Thousands, $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Jan. 01, 2019
Supplemental Cash Flow Elements [Line Items] |  |  |  |  |
Cash paid for interest | $ 76,379 | $ 44,697 | $ 32,429 |  |
State income, franchise and foreign taxes paid | 2,131 | $ 947 | $ 655 |  |
Issuance of OP units, number of units |  | 194 | 161 |  |
OP units issued in exchange of property contributed in UPREIT transactions | 0 | $ 15,797 | $ 12,913 |  |
Cancellation shares of common stock, shares |  | 9 |  |  |
Common stock cancelled, values |  | $ 748 |  |  |
Settlement of outstanding receivable with common stock |  | 748 |  |  |
Dividend declared and accrued but not yet paid | 12,162 | 10,111 | 8,449 |  |
Lease liabilities | 1,209 |  |  |  |
Payments for tenant improvements | $ 2,517 | 0 | $ 2,777 | $ 1,730 |
Notes receivables settled |  | $ 6,527 |  |  |
ASC 842 |  |  |  |  |
Supplemental Cash Flow Elements [Line Items] |  |  |  |  |
Right-of-use assets |  |  |  |  | $ 1,687
Lease liabilities |  |  |  |  | 1,261
Rent liability |  |  |  |  | 7
Ground lease intangible asset, net |  |  |  |  | $ 432
Distribution Reinvestment Plan |  |  |  |  |
Supplemental Cash Flow Elements [Line Items] |  |  |  |  |
Issuance of shares of common stock, shares | 753 | 622 | 499 |  |
Common stock issued | $ 63,020 | $ 50,826 | $ 38,848 |  |

X
- Definition Cancellation of common stock for outstanding receivable settlement . + References No definition available. + Details
Name: | ck1424182_CancellationOfCommonStockForOutstandingReceivableSettlement
Namespace Prefix: | ck1424182_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Cancellation shares of common stock, shares. + References No definition available. + Details
Name: | ck1424182_CancellationSharesOfCommonStockShares
Namespace Prefix: | ck1424182_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Cancellation shares of common stock, value. + References No definition available. + Details
Name: | ck1424182_CancellationSharesOfCommonStockValue
Namespace Prefix: | ck1424182_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Income franchise and foreign taxes paid. + References No definition available. + Details
Name: | ck1424182_IncomeFranchiseAndForeignTaxesPaid
Namespace Prefix: | ck1424182_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Supplemental cash flow elements. + References No definition available. + Details
Name: | ck1424182_SupplementalCashFlowElementsLineItems
Namespace Prefix: | ck1424182_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Carrying value as of the balance sheet date of obligations incurred through that date and payable for contractual rent under lease arrangements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(20)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(24)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(15)(5)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(15)(a)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 + Details
Name: | us-gaap_AccruedRentCurrentAndNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(24)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(15)(5)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(20)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(15)(5)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 + Details
Name: | us-gaap_DividendsPayableCurrentAndNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Net long-term land leases which are capitalized as part of real property. + References No definition available. + Details
Name: | us-gaap_GroundLeasesNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586 + Details
Name: | us-gaap_InterestPaid
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Present value of lessee's discounted obligation for lease payments from operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
Name: | us-gaap_OperatingLeaseLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of lessee's right to use underlying asset under operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
Name: | us-gaap_OperatingLeaseRightOfUseAsset
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Total change in each class of partners' capital accounts during the year due to exchanges and conversions. Partners include general, limited and preferred partners. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 5 -Subparagraph (SAB Topic 4.F) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
Name: | us-gaap_PartnersCapitalAccountExchangesAndConversions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The number of units converted into shares of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 5 -Subparagraph (SAB Topic 4.F) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
Name: | us-gaap_PartnersCapitalAccountUnitsConverted
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of cash outflow for the allowance granted to lessee and/or direct costs incurred by lessor used to prepare the leased premises for tenant's occupancy. + References No definition available. + Details
Name: | us-gaap_PaymentsForTenantImprovements
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The cash inflow associated with principal collections from a borrowing supported by a written promise to pay an obligation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585 + Details
Name: | us-gaap_ProceedsFromCollectionOfNotesReceivable
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The fair value of stock issued in noncash financing activities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586 + Details
Name: | us-gaap_StockIssued1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Number of new stock issued during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201602Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PlanNameAxis=ck1424182_DistributionReinvestmentPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |