Manager and Other Related Parties - Summary of Organization and Offering Expenses (Parenthetical) (Details)	12 Months Ended
Dec. 31, 2021 USD ($)
Related Party Transactions [Abstract]
Unallocated O&O expenses on units rebates period	120 months
Estimated future rebates on scheduled redemptions	$ 28,000

Unallocated organization and offering expenses repay period.

No definition available.

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Namespace Prefix:	ck0001448038_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration