Financing receivable, number of loans.

No definition available.

Name:	fscreit_FinancingReceivableNumberOfLoans
Namespace Prefix:	fscreit_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Loans Receivable Based On Internal Risk Ratings [Line Items]

+ References

No definition available.

+ Details

Name:	fscreit_LoansReceivableBasedOnInternalRiskRatingsLineItems
Namespace Prefix:	fscreit_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of carrying amount of mortgage loans.

+ References

No definition available.

+ Details

Name:	fscreit_PercentageOfCarryingAmountOfMortgageLoans
Namespace Prefix:	fscreit_
Data Type:	dtr-types:percentItemType
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:	us-gaap_InternalCreditAssessmentAxis=fscreit_RiskLevelVeryLowRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InternalCreditAssessmentAxis=us-gaap_RiskLevelLowMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InternalCreditAssessmentAxis=us-gaap_RiskLevelMediumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InternalCreditAssessmentAxis=us-gaap_RiskLevelHighMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InternalCreditAssessmentAxis=fscreit_RiskLevelVeryHighMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Loans Receivable, net - Summary of Loans Receivable Based on Internal Risk Ratings (Details) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2025 USD ($) loan	Dec. 31, 2024 USD ($) loan	Mar. 31, 2025 USD ($)	Jun. 30, 2024 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Loans Receivable Based on Internal Risk Ratings [Line Items]
Number of Loans \| loan	143	145
Net Book Value	$ 7,460,601	$ 7,496,474		$ 8,237,332		$ 7,782,219
Percentage	100.00%	100.00%
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
1
Loans Receivable Based on Internal Risk Ratings [Line Items]
Number of Loans \| loan	0	0
Net Book Value	$ 0	$ 0
Percentage	0.00%	0.00%
2
Loans Receivable Based on Internal Risk Ratings [Line Items]
Number of Loans \| loan	0	0
Net Book Value	$ 0	$ 0
Percentage	0.00%	0.00%
3
Loans Receivable Based on Internal Risk Ratings [Line Items]
Number of Loans \| loan	131	132
Net Book Value	$ 6,865,894	$ 6,831,933
Percentage	92.00%	92.00%
4
Loans Receivable Based on Internal Risk Ratings [Line Items]
Number of Loans \| loan	10	12
Net Book Value	$ 537,909	$ 559,541
Percentage	7.00%	7.00%
5
Loans Receivable Based on Internal Risk Ratings [Line Items]
Number of Loans \| loan	2	1
Net Book Value	$ 56,798	$ 105,000
Percentage	1.00%	1.00%