3. Restricted Marketable Securities (Details) - Restricted Marketable Securities - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	$ 200,243	$ 200,243	$ 198,310
Product minimum service life		25 years
Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	200,243	$ 200,243	198,310
Payments to acquire restricted marketable securities	7,900
Cash Held In Trust [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted cash and cash equivalents - noncurrent	1,800	1,800	6,200
Foreign government obligations [Member] \| Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	48,910	48,910	51,229
Supranational debt [Member] \| Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	22,900	22,900	15,339
U.S. debt [Member] \| Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	110,116	110,116	113,326
U.S. government obligations [Member] \| Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	$ 18,317	$ 18,317	$ 18,416

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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