Revenue from Contracts with Customers (Details) - USD ($)
$ in Millions

9 Months Ended

Jun. 30, 2026

Jun. 30, 2025

Sep. 30, 2025

Sep. 30, 2024

Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]

Revenue from Contract with Customer [Text Block]

Revenue from Contracts with Customers

We recognize revenue when control of products or services is transferred to our customers, in amounts that reflect the consideration to which we expect to receive in exchange for those products or services. We account for a contract when it has approval and commitment from both parties, the rights of the parties and the payment terms are identified, the contract has commercial substance, and collectability of consideration is probable. We determine the appropriate revenue recognition for our contracts with customers by analyzing the type, terms, and conditions of each customer contract or arrangement.

The table below presents the balances of our customer receivables and deferred revenue:


	June 30,		September 30,
	2026		2025

	(in millions)
Billed receivables	$	201.5	$	210.8
Unbilled receivables	3.7		4.7
Gross customer receivables	205.2		215.5
Allowance for credit losses	(2.0)		(3.6)
Receivables, net	$	203.2	$	211.9

Deferred revenue	$	10.9	$	12.1

Allowance for Credit Losses

Our condensed consolidated statements of operations include the expected credit losses either arising or changing during the period for our receivables. When we determine a receivable will not be collected, in whole or in part, we write-off the uncollectible amount against the allowance in that period. Our judgments of expected credit losses are based on prior collection experience, customer creditworthiness, forecasts of economic trends, and other current conditions, which may affect the collectability of the receivables. Differences between actual and expected industry or economic conditions could impact our customers’ ability to pay, resulting in actual credit losses differing from the amounts included in the allowance, and these differences could be significant.

The table below summarizes information concerning our allowance for credit losses:


	Nine months ended
	June 30,
	2026		2025
	(in millions)
Beginning balance	$	3.6	$	8.3
Release of provision, net	(0.3)		(0.2)
Write-offs and other	(1.3)		(2.8)
Ending balance	$	2.0	$	5.3

Contract Asset and Liability Balances

Differences in the timing of revenue recognition, billing, and cash collection result in customer receivables, advance payments, and billings in excess of revenue recognized. Customer receivables include amounts billed and currently due from customers as well as unbilled amounts, including contract assets. Amounts are billed in accordance with contractual terms and unbilled amounts arise when the timing of billing differs from the timing of when revenue is recognized.

Advance payments and billings in excess of revenue are recognized and recorded as deferred revenue and are classified as Other current liabilities or Other noncurrent liabilities in the accompanying condensed consolidated balance sheets based on the timing of when we expect to recognize revenue. Deferred revenue represents contract liabilities and is recorded when customers remit cash payments in advance of our satisfaction of performance obligations pursuant to contractual arrangements. Contract liabilities are reversed when the performance obligation is satisfied and revenue is recognized. Deferred revenue primarily consists of amounts related to monitoring, leak detection, software, and hosting services.

The table below summarizes information related to deferred revenue:


	Nine months ended
	June 30,
	2026		2025
	(in millions)
Beginning balance	$	12.1	$	12.8
Revenue deferred	7.8		6.2
Previously deferred revenue recognized during the period	(7.8)		(7.7)
Other	(1.2)		—
Ending balance	$	10.9	$	11.3

As of June 30, 2026, current deferred revenue was $5.9 million and noncurrent deferred revenue was $5.0 million. We estimate that noncurrent deferred revenue will be recognized as follows: $0.3 million in 2027, $1.1 million in 2028, $1.1 million in 2029, $1.1 million in 2030, $0.6 million in 2031, and $0.8 million thereafter.

Performance Obligations

A performance obligation is a promise in a contract to transfer a distinct good or service to the customer. Our performance obligations are generally satisfied at a point in time for sales of equipment and products or over time for our software hosting and leak detection monitoring services. Performance obligations are supported by customer contracts which provide frameworks for the nature of the distinct products or services. The transaction price is adjusted for our estimate of variable consideration which may include discounts and rebates. To estimate variable consideration, we apply the expected value or the most likely amount method based on whichever method most appropriately predicts the amount of consideration we expect to receive. The method applied is typically based on historical experience and known trends. We include estimated variable consideration in the transaction price only to the extent it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur in future periods when the uncertainty associated with the variable consideration is subsequently resolved. We exclude from the measurement of the transaction price all taxes assessed by a governmental authority.

We do not adjust the transaction price of a contract for the effects of a significant financing component if, at the inception of the contract, we expect that the period between when we transfer a product or service to a customer and when a customer remits payment will be one year or less.

Revenue for the sale of our products and services is recognized when the obligations of the terms of our contract are satisfied, which is when the customer is able to direct the use of and obtain substantially all of the benefits from the product or service, which generally occurs upon shipment when control of the product transfers to the customer or the service is completed.

We offer assurance warranties to our customers that the products provided will function as intended and comply with any agreed-upon specifications. These warranties cannot be purchased separately. On limited products, we offer extended warranties, which may be purchased separately.

Costs to Obtain or Fulfill a Contract

Shipping and handling costs associated with freight activities after the customer has obtained control are accounted for as fulfillment costs and are expensed to Cost of sales within our condensed consolidated statement of operations at the time revenue is recognized.

We incur certain incremental costs to obtain a contract, which primarily relate to incremental sales commissions. As the expected benefit associated with these incremental costs is generally one year or less based on the nature of the product sold and benefits received, we have applied the practical expedient to expense them as incurred and therefore do not capitalize the related costs. Our sales commissions are paid based on orders or shipments, and we reserve the right to claw back any commissions in the event of product returns, cancellations, or lost collections.

Disaggregation of Revenue

Refer to Note 7. for information regarding disaggregation of our revenues from contracts with customers by reportable segment and by geographical region based on customer location. Economic factors may impact the nature, amount, timing, and certainty of our revenues and cash flows.

Revenue deferred

$ 7.8

$ 6.2

Previously deferred revenue recognized during the period

(7.8)

(7.7)

Deferred Revenue Transferred in Portfolio Optimization Activities

(1.2)

0.0

Billed Contracts Receivable

201.5

$ 210.8