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Credit Facility - Additional Information (Details) - Wells Fargo Bank, National Association [Member] - Credit Facility [Member]
3 Months Ended
Mar. 31, 2022
USD ($)
Mar. 31, 2022
USD ($)
Line Of Credit Facility [Line Items]    
Secured revolving credit facility $ 7,000,000.0 $ 7,000,000.0
Maturity date Mar. 31, 2023  
Ratio of sum of cash plus marketable securities, plus accounts receivable to principal balance outstanding of Credit Facility 2.0  
Borrowings outstanding $ 0 $ 0
Secured Overnight Financing Rate [Member]    
Line Of Credit Facility [Line Items]    
Interest rate description   secured overnight financing rate plus 2%
Basis spread on variable rate 2.00%  
Available for Letters of Credit [Member]    
Line Of Credit Facility [Line Items]    
Secured revolving credit facility $ 500,000 $ 500,000