Loan, Interest Rate

No definition available.

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- Definition

Loan to unaffiliated third party

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Loans Receivable

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Term, in years, of the typical amortization used on loans made.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Largest principal balance on a single loan in the secured loan portfolio.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Loans receivable maturity date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Loans Receivable Number Of Interest And Principal Loans

+ References

No definition available.

+ Details

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

- Definition

Loans Receivable Number Of Interest Only Loans.

+ References

No definition available.

+ Details

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Namespace Prefix:	ck0001448038_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the loans receivable, percent of aggregate principal.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Loans receivable, yield of loan acquired.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Mortgage Loan, Principal Count Of Loans, Renewed

+ References

No definition available.

+ Details

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

- Definition

Mortgage Loans On Real Estate Principal Amount Of Loan

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Mortgage Loans On Real Estate Principal Amount Of Loans At Funding

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Mortgage loans on real estate principal renewed.

+ References

No definition available.

+ Details

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Namespace Prefix:	ck0001448038_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number of loan.

+ References

No definition available.

+ Details

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

- Definition

Number Of Non Performing Loans Due

+ References

No definition available.

+ Details

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

- Definition

Percentage of loan to value.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Principal Non Performing Loans

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Number of mortgage loans within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 29
-Paragraph Column A
-Footnote 3
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478322/948-310-S50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column A)(Footnote 3))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479628/948-310-S99-1

+ Details

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Namespace Prefix:	srt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of principal due on delinquent mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 29
-Paragraph Column H
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479628/948-310-S99-1

+ Details

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Namespace Prefix:	srt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(13)(h))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of commitment to lend additional funds to debtor experiencing financial difficulty for which creditor has modified terms of financing receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481746/310-40-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 36
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-36

+ Details

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

- Definition

The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 80
-Name Accounting Standards Codification
-Section 55
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480078/944-80-55-14

Reference 2: http://www.xbrl.org/2003/role/exampleRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
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-Publisher FASB
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-SubTopic 210
-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

+ Details

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- Details

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Loans - Additional Information (Details) $ in Thousands	3 Months Ended		6 Months Ended
Loans - Additional Information (Details) $ in Thousands	Jun. 30, 2025 USD ($) Loan	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) Loans Loan	Jun. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Mortgage Loan, Principal Count Of Loans, Renewed \| Loan	1		3
Loan to unaffiliated third party	$ 1,100		$ 1,100
Principal	45,185		$ 45,185		$ 53,475	$ 53,475
Total principal, secured loans, Loans \| Loans			29
Principal	45,185		$ 45,185		53,475
Commitment to Lend, Outstanding	0		0
Largest secured loan - principal	$ 7,400		$ 7,400		8,106
Loan, interest rate	8.99%		8.99%
Number of loans \| Loan			0
Aggregate principal renewed	$ 241		$ 4,000
Gain on sale, loans	0	$ 24	$ 8	$ 24
Loans receivable, amortization term			30 years
Past Due 180 or More Days [Member]
Principal	3,200		$ 3,200
Principal	8,280		$ 8,280		6,690
Number of loans \| Loan			3
Principal non performing loans	5,600		$ 5,600
Loan Payment Modification Agreement [Member] \| Past Due 180 or More Days [Member]
Principal	990		990		$ 990
Delinquent Loan [Member]
Principal	9,100		9,100
Principal	5,800		5,800
CECL Model [Member]
Principal	5,800		5,800
Principal at Funding	9,100		$ 9,100
Second Lien [Member]
Number of loans \| Loans			6
Loans receivable	$ 5,400		$ 5,400
Loans receivable, yield of loan acquired	54.00%		54.00%
Interest Only [Member]
Loans receivable number of interest only loans \| Loan	21		21
Principal	$ 39,300		$ 39,300
Interest and Principal Loans [Member]
Loans receivable, percent of aggregate principal	13.00%		13.00%
Principal	$ 5,900		$ 5,900
Loans receivable number of interest and principal loans \| Loan	8		8
Largest Loan [Member]
Largest secured loan - principal	$ 7,400		$ 7,400
Loan, interest rate	12.50%		12.50%
Loans receivable maturity date			Mar. 01, 2026
First lien Position [Member] \| Past Due 180 or More Days [Member]
Non performing number of loans \| Loan	5		5
Secured Debt [Member] \| Delinquent Loan [Member]
Principal	$ 842		$ 842
Secured Debt [Member] \| Second Lien [Member] \| Delinquent Loan [Member]
Principal	$ 760		$ 760			$ 1,900
Loan, interest rate	8.88%		8.88%			11.25%
Loans receivable maturity date			Aug. 01, 2023
LTV percentage						47.00%
Secured Debt [Member] \| Second Lien [Member] \| Other Delinquent Loan [Member]
Principal	$ 600		$ 600
Loans receivable maturity date			Jun. 01, 2025
LTV percentage	71.00%		71.00%
First Mortgage Loans [Member]
Loans receivable, percent of aggregate principal	88.00%		88.00%		88.00%