Long-Term Debt - Schedule of Convertible Debt (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Debt Instrument [Line Items]
Unamortized Issuance Costs	$ (16,814)		$ (17,396)
Total Debt	2,226,873		2,214,121
Equity Component, net of Purchase Discounts and Issuance Costs		$ (33)
Convertible Senior Notes Due 2026
Debt Instrument [Line Items]
Total Debt	336,810		253,716
Convertible Debt \| Convertible Senior Notes Due 2026
Debt Instrument [Line Items]
Principal	345,000		345,000
Unamortized Discount	0		(85,950)
Unamortized Issuance Costs	(8,190)		(5,334)
Total Debt	336,810		253,716
Fair Value	603,609		453,765
Equity Component, net of Purchase Discounts and Issuance Costs	$ 0		$ 78,284

Adjustment to additional paid in capital resulting from the recognition of convertible debt instruments as two separate components - a debt component and an equity component. This bifurcation may result in a basis difference associated with the liability component that represents a temporary difference for purposes of applying accounting for income taxes. The initial recognition of deferred taxes for the tax effect of that temporary difference is as an adjustment to additional paid in capital.

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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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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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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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