Summary of Significant Accounting Policies - Schedule of Deferred Revenue (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2023
Deferred Revenue Arrangement [Line Items]
Deferred revenue	$ 1,481,181	$ 1,338,347	$ 1,200,000
Under Customer Agreements:
Deferred Revenue Arrangement [Line Items]
Deferred revenue	1,113,435	1,029,956
Under Customer Agreements: | Payments received, net
Deferred Revenue Arrangement [Line Items]
Deferred revenue	1,028,064	950,225
Under Customer Agreements: | Financing component balance
Deferred Revenue Arrangement [Line Items]
Deferred revenue	85,371	79,731
Under SREC contracts:
Deferred Revenue Arrangement [Line Items]
Deferred revenue	367,746	308,391
Under SREC contracts: | Payments received, net
Deferred Revenue Arrangement [Line Items]
Deferred revenue	348,101	291,972
Under SREC contracts: | Financing component balance
Deferred Revenue Arrangement [Line Items]
Deferred revenue	$ 19,645	$ 16,419