Income (loss) from unconsolidated real estate ventures.

No definition available.

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Balance Type:	credit
Period Type:	duration

- Definition

Number of real estate properties acquired during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

+ Details

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Period Type:	duration

- Definition

The carrying amount of investments in unconsolidated real estate and other joint ventures not separately presented. This includes direct and indirect investments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(d))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

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Balance Type:	debit
Period Type:	instant

- 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

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- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123419778&loc=SL6759159-111685

+ Details

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Period Type:	duration

- Details

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- Details

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- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=ck1711929_BelowMarketLeasesMember
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Data Type:	na
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- Details

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Balance Type:
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- Details

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=ck1711929_IndustrialAssetsMember
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- Details

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- Details

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- Details

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=ck1711929_SingleFamilyRentalUnitsMember
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- Details

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Investments - Additional Information (Details) $ in Thousands		3 Months Ended
	Mar. 13, 2019	Mar. 31, 2022 USD ($) Property	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($) Property
Real Estate Properties [Line Items]
Number of acquired real estate properties		3		244
Percentage of ownership interest in joint venture	43.00%
Investment in joint venture \| $		$ 11,351		$ 10,422
Income (loss) from Unconsolidated Real Estate Ventures \| $		$ 929	$ (22)
In-place Lease Intangibles
Real Estate Properties [Line Items]
Weighted-average amortization period		5 years
Above Market Leases Intangibles
Real Estate Properties [Line Items]
Weighted-average amortization period		3 years
Below Market Leases Intangibles
Real Estate Properties [Line Items]
Weighted-average amortization period		6 years
Multifamily
Real Estate Properties [Line Items]
Number of acquired real estate properties				151
Industrial Assets
Real Estate Properties [Line Items]
Number of acquired real estate properties		2		60
Office Buildings
Real Estate Properties [Line Items]
Number of acquired real estate properties				5
Self-Storage Properties
Real Estate Properties [Line Items]
Number of acquired real estate properties		1		25
Single Family Rental Homes
Real Estate Properties [Line Items]
Number of acquired real estate properties		114		2,595
Other Property
Real Estate Properties [Line Items]
Number of acquired real estate properties				3