CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities
Net income	$ 2,163,193	$ 49,776
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	26,005	31,543
Stock-based compensation	7,230	14,191
Amortization of premium on marketable securities and deferred financing costs	66	113
Deferred income taxes	11,054	(10,161)
Loss on extinguishment of debt	632
(Gain) loss on disposals of property, plant and equipment	(30)	51
Gain on divestiture, net of tax	(2,130,351)
Adjustment to the gain on divestiture of semiconductor cryogenics business, net of tax		948
Fees paid stemming from divestiture	(52,461)
Changes in operating assets and liabilities, net of acquisitions and divestiture:
Accounts receivable	(456)	(35,033)
Inventories	(55,033)	(11,301)
Prepaid expenses and other assets	(48,891)	3,157
Accounts payable	(7,906)	14,136
Deferred revenue	5,215	4,659
Accrued warranty and retrofit costs	(198)	(261)
Accrued compensation and tax withholdings	10,875	(5,371)
Accrued restructuring costs	(113)	(124)
Accrued expenses and other liabilities	15,430	21,619
Net cash (used in) provided by operating activities	(55,739)	77,942
Cash flows from investing activities
Purchases of property, plant and equipment	(44,326)	(25,531)
Purchases of technology intangibles	(4,000)
Purchases of marketable securities	(1,074,428)	(75)
Sales of marketable securities	3,710	25
Proceeds from divestiture, net of cash transferred	2,927,245
Adjustment to proceeds from divestiture of semiconductor cryogenics business		(1,802)
Net cash provided by (used in) investing activities	1,808,201	(27,383)
Cash flows from financing activities
Proceeds from issuance of common stock	3,461	2,583
Principal payments on debt	(49,725)	(414)
Payments of finance leases	(312)	(638)
Payment for contingent consideration related to acquisition	(9,400)
Common stock dividends paid	(7,494)	(14,856)
Net cash used in financing activities	(63,470)	(13,325)
Effects of exchange rate changes on cash and cash equivalents	(25,372)	6,051
Net increase in cash, cash equivalents and restricted cash	1,663,620	43,285
Cash, cash equivalents and restricted cash, beginning of period	285,333	302,526
Cash, cash equivalents and restricted cash, end of period	$ 1,948,953	$ 345,811