CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
CURRENT ASSETS:
Cash and cash equivalents	$ 74,012	$ 91,985
Short-term investments	465,293	422,137
Accounts receivable	119,584	139,850
Inventory	172,905	175,795
Other current assets	89,478	87,365
Total current assets	921,272	917,132
PROPERTY AND EQUIPMENT, net of accumulated depreciation of $149,062 and $143,908	175,896	175,150
ACQUIRED TECHNOLOGY, net of accumulated amortization of $191,043 and $186,850	86,132	90,325
OTHER INTANGIBLE ASSETS, net of accumulated amortization of $10,769 and $10,414	6,519	6,874
GOODWILL	15,535	15,535
INVESTMENTS	312,939	299,548
DEFERRED INCOME TAXES	63,040	59,108
OTHER ASSETS	102,382	105,289
TOTAL ASSETS	1,683,715	1,668,961
CURRENT LIABILITIES:
Accounts payable	12,841	10,933
Accrued expenses	42,099	52,080
Deferred revenue	19,157	47,713
Other current liabilities	20,882	8,096
Total current liabilities	94,979	118,822
DEFERRED REVENUE	13,292	12,006
RETIREMENT PLAN BENEFIT LIABILITY	52,568	52,249
OTHER LIABILITIES	37,976	38,658
Total liabilities	198,815	221,735
COMMITMENTS AND CONTINGENCIES (Note 18)
SHAREHOLDERS' EQUITY:
Preferred Stock, par value $0.01 per share, 5,000,000 shares authorized, 200,000 shares of Series A Nonconvertible Preferred Stock issued and outstanding (liquidation value of $7.50 per share or $1,500)	2	2
Common Stock, par value $0.01 per share, 200,000,000 shares authorized, 48,804,964 and 48,731,026 shares issued, and 47,439,316 and 47,365,378 shares outstanding, at March 31, 2024 and December 31, 2023, respectively	488	487
Additional paid-in capital	702,609	699,554
Retained earnings	826,879	789,553
Accumulated other comprehensive loss	(3,794)	(1,086)
Treasury stock, at cost (1,365,648 shares at March 31, 2024 and December 31, 2023)	(41,284)	(41,284)
Total shareholders’ equity	1,484,900	1,447,226
TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY	$ 1,683,715	$ 1,668,961