Investments in Affiliates - Summary of Transactions in, and Earnings from, Investments in Affiliates (Parathetical) (Detail) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Investments In And Advances To Affiliates Schedule Of Investments [Abstract]
Capital gain distributions from Affiliated Investments	$ 1,939	$ 7,156

Net realized gain (loss) on capital gain distributions from affiliated investments.

No definition available.

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