Related Party Transactions - Additional Information (Details) - USD ($)	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Related Party Transaction [Line Items]
Balance with Fund Manager	$ 15,511,000		$ 19,062,000
Maximum [Member]
Related Party Transaction [Line Items]
Fund management fee percent	0.25%
Other Income (Expense) [Member]
Related Party Transaction [Line Items]
Investment income generated from mutual funds	$ 174,000	$ 15,000
Cash and Cash Equivalents [Member]
Related Party Transaction [Line Items]
Balance with Fund Manager	9,557,000		13,282,000
Marketable Securities [Member]
Related Party Transaction [Line Items]
Balance with Fund Manager	$ 5,954,000		$ 5,780,000