Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 89,104	$ 108,212
Current investments	364,487	427,348
Accounts receivable, less reserves of $1,778 and $1,646 in 2019 and 2018, respectively	107,643	119,172
Unbilled revenue	10,300	8,312
Inventories	72,889	83,282
Prepaid expenses and other current assets	34,451	34,000
Total current assets	678,874	780,326
Non-current investments	408,032	262,039
Property, plant, and equipment, net	89,342	91,396
Operating Lease, Right-of-Use Asset	17,928	0
Goodwill	113,208	113,208
Intangible assets, net	8,575	10,113
Deferred income taxes	28,537	28,660
Other assets	5,424	3,925
Total assets	1,349,920	1,289,667
Current liabilities:
Accounts payable	11,729	16,230
Accrued expenses	48,709	60,220
Accrued income taxes	1,078	5,062
Deferred revenue and customer deposits	18,332	9,845
Operating Lease, Liability, Current	5,835	0
Total current liabilities	85,683	91,357
Operating Lease, Liability, Noncurrent	12,149	0
Deferred income taxes	0	962
Reserve for income taxes	8,091	7,106
Non-current accrued income taxes	51,113	51,113
Other liabilities	1,244	3,866
Total liabilities	158,280	154,404
Preferred Stock, Value, Outstanding	0	0
Shareholders’ equity:
Common stock, $.002 par value – Authorized: 300,000 shares in 2019 and 2018, respectively, issued and outstanding: 170,661 and 170,820 shares in 2019 and 2018, respectively	341	342
Additional paid-in capital	578,871	529,208
Retained earnings	649,234	646,214
Accumulated other comprehensive loss, net of tax	(36,806)	(40,501)
Total shareholders’ equity	1,191,640	1,135,263
Total liabilities and shareholders' equity	$ 1,349,920	$ 1,289,667