3. Restricted Marketable Securities (Details) - Restricted Marketable Securities - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	$ 210,555	$ 199,136
Product minimum service life	25 years
Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	$ 210,555	199,136
Payments to acquire restricted marketable securities	5,000
Cash Held In Trust [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted cash and cash equivalents - noncurrent	2,800	5,000
U.S. debt [Member] \| Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	113,048	109,155
Foreign government obligations [Member] \| Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	50,592	49,024
Supranational debt [Member] \| Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	28,118	22,809
U.S. government obligations [Member] \| Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	$ 18,797	$ 18,148

Describes the solar modules minimum service life.

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Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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The cash outflow to acquire investments (not to include restricted cash) that are pledged or subject to withdrawal restrictions.

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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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