Long-Term Debt - Summary of Long-Term Debt (Detail) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Line of Credit Facility [Line Items]
Less unamortized debt issuance costs	$ (6,210,108)	$ (5,154,620)
Long-term debt	300,000,000	263,500,000
Long-term debt, net of current portion	293,789,892	258,345,380
Secured Notes [Member]
Line of Credit Facility [Line Items]
Total debt	$ 300,000,000
Term Loan [Member]
Line of Credit Facility [Line Items]
Total debt		238,000,000
Revolving Credit Loan [Member]
Line of Credit Facility [Line Items]
Total debt		20,000,000
Promissory Note [Member]
Line of Credit Facility [Line Items]
Total debt		$ 5,500,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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