Long Term Debt - Summary of Components of Long-term Debt (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Total debt	$ 528,676	$ 527,132
Less: unamortized original issue discount	(13,760)	(14,700)
Less: unamortized debt issuance costs	(1,615)	(1,726)
Total debt, net	513,301	510,706
Current portion of debt	3,000	3,000
Total current portion of debt, net	3,000	3,000
Long-term debt, net	510,301	507,706
Convertible Debenture Notes
Debt Instrument [Line Items]
Total debt	231,676	229,382
2021 Credit Agreement
Debt Instrument [Line Items]
Total debt	$ 297,000	$ 297,750

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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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 accumulated amortization, of debt discount.

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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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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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