Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Cash flows from operating activities
Net loss	$ (53,796)	$ (152,604)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization	32,053	44,214
Impairment of goodwill and intangible assets	0	115,975
Long Lived Assets To Be Sold	24,187	0
Inventory write-downs and other asset write-offs	4,326	7,499
Stock-based compensation	13,453	8,804
Amortization and accretion on marketable securities	(983)	(2,084)
Deferred income taxes	(1,885)	(9,456)
(Gain) loss on disposals of property, plant and equipment	(7)	260
Changes in operating assets and liabilities:
Accounts receivable	6,713	2,922
Inventories	(6,030)	8,238
Accounts payable	1,864	936
Deferred revenue	12,042	3,379
Accrued warranty and retrofit costs	343	(714)
Accrued compensation and tax withholdings	(2,379)	(7,831)
Accrued restructuring costs	1,548	1,454
Other assets and liabilities	12,752	1,379
Net cash provided by operating activities	44,201	22,371
Cash flows from investing activities
Purchases of property, plant and equipment	(15,158)	(19,542)
Purchases of marketable securities	(236,237)	(345,447)
Sales and maturities of marketable securities	184,636	190,504
Proceeds from other investment	2,130	0
Net investment hedge settlement	3,043	1,476
Net cash used in investing activities	(61,586)	(173,009)
Cash flows from financing activities
Proceeds from issuance of common stock	1,553	1,678
Payments of finance leases	(457)	(386)
Share repurchases	0	(186,834)
Excise tax payment for settled share repurchases	(11,376)	0
Net cash used in financing activities	(10,280)	(185,542)
Effects of exchange rate changes on cash, cash equivalents and restricted cash	(4,459)	16,255
Net decrease in cash, cash equivalents and restricted cash	(32,124)	(319,925)
Cash, cash equivalents and restricted cash, beginning of period	320,990	684,045
Cash, cash equivalents and restricted cash, end of period	288,866	364,120
Supplemental disclosures:
Cash (received) / paid for income taxes, net	(4,594)	5,008
Purchases of property, plant and equipment included in accounts payable and accrued expenses	$ 5,773	$ 2,270