Contract Balance - Receivables (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Sep. 30, 2024
Revenue from Contract with Customer [Abstract]
Billed	$ 207,719	$ 264,942
Unbilled	200,702	210,795
Receivables Gross	408,421	475,737
Less: allowance for doubtful accounts	(6,943)	(6,454)
Accounts Receivable, after Allowance for Credit Loss	401,478	469,283
Less: long-term receivables	(50,554)	(42,641)
Accounts receivable, net	$ 350,924	$ 426,642

Receivables, Gross

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- Definition

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as noncurrent.

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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