Restructuring - Schedule of Restructuring-related Liabilities (Detail) - 2025 Plan - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2026	Dec. 31, 2025
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 468
Cash Restructuring-Related Liabilities Roll-Forward
Restructuring Cost and Reserve [Line Items]
Beginning Balance	7,725
Restructuring charges	347	$ 8,479
Payments	(6,808)	(754)
Change in estimate	121
Ending Balance	1,385	7,725
Employee Termination Benefit Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	342
Employee Termination Benefit Costs \| Cash Restructuring-Related Liabilities Roll-Forward
Restructuring Cost and Reserve [Line Items]
Beginning Balance	7,725
Restructuring charges	221	8,395
Payments	(6,746)	(670)
Change in estimate	121
Ending Balance	1,321	7,725
Other Cash Restructuring Charges
Restructuring Cost and Reserve [Line Items]
Restructuring charges	126
Other Cash Restructuring Charges \| Cash Restructuring-Related Liabilities Roll-Forward
Restructuring Cost and Reserve [Line Items]
Restructuring charges	126	84
Payments	(62)	$ (84)
Ending Balance	$ 64

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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