Percentage of carrying amount of mortgage loans.

No definition available.

Name:	fscreit_PercentageOfCarryingAmountOfMortgageLoans
Namespace Prefix:	fscreit_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- 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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

+ Details

Name:	us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

+ Details

Name:	us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

+ Details

Name:	us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	srt_StatementGeographicalAxis=fscreit_SouthMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=fscreit_WestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=fscreit_NortheastMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=fscreit_VariousMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=fscreit_MidwestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Loans Receivable, net - Summary of Loan Receivables Acquired By Geographic Area (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2025	Dec. 31, 2024	Mar. 31, 2025	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	$ 7,460,601	$ 7,496,474		$ 8,237,332		$ 7,782,219
CECL reserve	(99,816)	(93,664)	$ (82,805)	(139,402)	$ (119,800)	$ (79,851)
Loans receivable, net	$ 7,360,785	$ 7,402,810		$ 8,097,930
Percentage	100.00%	100.00%
South
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	$ 3,389,271	$ 3,399,087
Percentage	45.00%	45.00%
West
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	$ 1,561,354	$ 1,509,283
Percentage	21.00%	20.00%
Northeast
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	$ 1,395,830	$ 1,576,005
Percentage	19.00%	21.00%
Various
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	$ 639,768	$ 675,558
Percentage	9.00%	9.00%
Midwest
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	$ 474,378	$ 336,541
Percentage	6.00%	5.00%