Loans - Secured Loan Principal Transactions (Parenthetical) (Additional Information) (Details) - USD ($)	Jan. 31, 2022	Dec. 31, 2021
Receivables [Abstract]
Amount Includes Principal Collected and Held in Trust		$ 1,000
Amount disbursed against loan	$ 48,000

Amount Includes Principal Collected and Held in Trust.

No definition available.

Name:	ck0001448038_AmountIncludesPrincipalCollectedAndHeldInTrust
Namespace Prefix:	ck0001448038_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant