CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
Current assets
Cash and cash equivalents	$ 320,105	$ 295,649
Marketable securities	101	67
Accounts receivable, net	225,389	188,291
Inventories	127,987	114,834
Prepaid expenses and other current assets	50,908	50,612
Total current assets	724,490	649,453
Property, plant and equipment, net	132,420	117,665
Long-term marketable securities	3,485	3,101
Long-term deferred tax assets	9,864	4,979
Goodwill	513,093	501,536
Intangible assets, net	209,899	218,325
Other assets	70,845	64,066
Total assets	1,664,096	1,559,125
Current liabilities
Current portion of long-term debt	414	827
Accounts payable	77,741	61,758
Deferred revenue	36,793	31,357
Accrued warranty and retrofit costs	8,044	8,201
Accrued compensation and benefits	38,504	43,267
Accrued restructuring costs	58	181
Accrued income taxes payable	23,889	10,094
Accrued expenses and other current liabilities	80,203	55,433
Total current liabilities	265,646	211,118
Long-term debt	49,653	49,588
Long-term tax reserves	19,707	19,168
Long-term deferred tax liabilities	15,442	17,798
Long-term pension liabilities	6,353	6,406
Long-term operating lease liabilities	32,749	31,855
Other long-term liabilities	8,520	9,578
Total liabilities	398,070	345,511
Commitments and contingencies (Note 17)
Stockholders' Equity
Preferred stock, $0.01 par value - 1,000,000 shares authorized, no shares issued or outstanding
Common stock, $0.01 par value - 125,000,000 shares authorized, 87,755,666 shares issued and 74,293,797 shares outstanding at March 31, 2021, 87,293,710 shares issued and 73,831,841 shares outstanding at September 30, 2020	878	873
Additional paid-in capital	1,959,619	1,942,850
Accumulated other comprehensive income	22,637	21,919
Treasury stock, at cost- 13,461,869 shares	(200,956)	(200,956)
Accumulated deficit	(516,152)	(551,072)
Total stockholders' equity	1,266,026	1,213,614
Total liabilities and stockholders' equity	$ 1,664,096	$ 1,559,125