Convertible Notes (Schedule of Notes) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Nov. 17, 2017
Debt instrument
Less current portion	$ 10,378	$ 163,687
1.375% Convertible senior notes due 2023 \| Convertible senior notes
Debt instrument
Face value	10,381	172,500	$ 172,500
Unamortized discount	0	(8,266)
Unamortized debt issuance costs	(3)	(547)
Total convertible notes	10,378	163,687
Less current portion	10,378	163,687
Total long-term convertible notes	$ 0	$ 0

Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Convertible Notes Payable, excluding current portion. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.

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Carrying value as of the balance sheet date of the portion of long-term debt due within one year or the operating cycle if longer identified as Convertible Notes Payable. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.

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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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