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 equivalent restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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3. Restricted Marketable Securities (Details) - Restricted Marketable Securities - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	$ 202,497		$ 217,172
Product minimum service life	25 years
Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	$ 202,497		217,172
Payments to acquire restricted marketable securities	0	$ 5,000
Cash Held In Trust [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted cash and cash equivalents - noncurrent	13,300		6,900
U.S. debt [Member] \| Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	107,130		115,350
Foreign government obligations [Member] \| Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	50,490		54,156
Supranational debt [Member] \| Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	27,318		28,276
U.S. government obligations [Member] \| Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted marketable securities	$ 17,559		$ 19,390