Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Operating activities:
Consolidated net income	$ 53,600	$ 25,426	$ 56,629
Adjustments to reconcile consolidated net income to net cash provided by operating activities:
Depreciation and amortization	17,240	13,776	11,705
Stock-based compensation expense	12,869	10,264	7,035
Provision for doubtful accounts	43	5	0
Deferred income taxes	(34)	(72)	18
Litigation-contingency expense	0	6,500	0
Amortization of bond premium	0	1,056	0
Credit gain on available-for-sale securities	0	(3)	(4)
Increase (decrease) in long-term deferred revenue	875	(268)	(320)
Increase in other assets	(192)	(692)	(43)
Increase (decrease) in long-term income taxes payable	1,366	293	(74)
Decrease in contingent consideration obligations	0	0	(74)
Change in current assets and liabilities, net	(11,239)	(33,346)	(20,428)
Net cash provided by operating activities	74,528	22,939	54,444
Investing activities:
Purchases of short-term investments	0	0	(70,900)
Additions to property, plant and equipment and internal-use software	(33,452)	(63,966)	(47,761)
Sales and maturities of short-term investments	0	45,000	75,000
Net cash used for investing activities	(33,452)	(18,966)	(43,661)
Financing activities:
Proceeds from employee stock plans	10,602	4,439	10,243
Payment of contingent consideration obligations	0	0	(153)
Net cash provided by financing activities	10,602	4,439	10,090
Effect of foreign exchange rates on cash	(70)	(219)	(197)
Net increase in cash and cash equivalents	51,608	8,193	20,676
Cash and cash equivalents at beginning of year	190,611	182,418	161,742
Cash and cash equivalents at end of year	242,219	190,611	182,418
Change in current assets and liabilities:
Accounts receivable	12,640	(10,586)	(14,301)
Inventories	(5,236)	(34,204)	(10,134)
Other current assets	(539)	1,547	10
Accounts payable and accrued liabilities	(11,151)	4,399	2,503
Accrued severance and other charges	9	(93)	93
Short-term lease liabilities	583	103	4
Income taxes payable	674	6	(73)
Deferred revenue and customer prepayments	(8,219)	5,482	1,470
Change in current assets and liabilities, net	(11,239)	(33,346)	(20,428)
Supplemental disclosures:
Cash paid during the year for income taxes, net of refunds	4,151	1,263	645
Purchases of property, plant and equipment and internal-use software incurred but not yet paid	$ 2,168	$ 4,194	$ 4,803