Long Term Debt - Summary of Components of Long-term Debt (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Total debt	$ 530,268	$ 527,132
Less: unamortized original issue discount	(12,788)	(14,700)
Less: unamortized debt issuance costs	(1,506)	(1,726)
Total debt, net	515,974	510,706
Current portion of debt	3,000	3,000
Total current portion of debt, net	3,000	3,000
Long-term debt, net	512,974	507,706
Convertible Debenture Notes
Debt Instrument [Line Items]
Total debt	234,018	229,382
2021 Credit Agreement
Debt Instrument [Line Items]
Total debt	$ 296,250	$ 297,750

Amount of debt and lease obligation, classified as current.

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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, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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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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