Revenue from Contracts with Customers - Revenue by Contracts (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Disaggregation of Revenue [Line Items]
Total revenue	$ 186,788	$ 363,956
Revenue from energy storage products and solutions
Disaggregation of Revenue [Line Items]
Total revenue	169,752	356,941
Revenue from services
Disaggregation of Revenue [Line Items]
Total revenue	15,666	5,747
Revenue from digital applications and solutions
Disaggregation of Revenue [Line Items]
Total revenue	$ 1,370	$ 1,268

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.

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details