Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 28, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 286,021	$ 171,431
Current investments, amortized cost of $141,874 and $235,610 in 2020 and 2019, respectively, allowance for expected credit losses of $0 in 2020 and 2019	143,084	240,470
Accounts receivable, less reserves of $2,235 and $1,821 in 2020 and 2019, respectively	111,671	103,447
Unbilled revenue	978	4,782
Inventories	52,953	60,261
Prepaid expenses and other current assets	51,768	26,840
Total current assets	646,475	607,231
Non-current investments, amortized cost of $461,948 and $431,633 in 2020 and 2019, respectively, allowance for expected credit losses of $75 and $0 in 2020 and 2019, respectively	467,087	433,452
Property, plant, and equipment, net	83,936	89,443
Operating lease assets	25,819	17,522
Goodwill	242,436	243,445
Intangible assets, net	17,337	39,490
Deferred income taxes	443,732	449,519
Other assets	8,042	5,833
Total assets	1,934,864	1,885,935
Current liabilities:
Accounts payable	17,999	17,866
Accrued expenses	66,264	52,199
Accrued income taxes	5,952	30,333
Deferred revenue and customer deposits	46,738	14,432
Operating lease liabilities	7,628	5,647
Total current liabilities	144,581	120,477
Operating Lease, Liability, Noncurrent	21,208	12,326
Deferred income taxes	326,295	332,344
Reserve for income taxes	12,302	11,563
Non-current accrued income taxes	48,915	51,113
Other liabilities	5,085	2,402
Total liabilities	558,386	530,225
Preferred Stock, Value, Outstanding	0	0
Shareholders’ equity:
Common stock, $.002 par value – Authorized: 300,000 shares in 2020 and 2019, respectively, issued and outstanding: 173,047 and 172,440 shares in 2020 and 2019, respectively	346	345
Additional paid-in capital	710,412	639,372
Retained earnings	702,597	753,268
Accumulated other comprehensive loss, net of tax	(36,877)	(37,275)
Total shareholders’ equity	1,376,478	1,355,710
Total liabilities and shareholders' equity	$ 1,934,864	$ 1,885,935