Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 77,808	$ 90,860
Short-term investments	173,693	144,103
Accounts receivable, net	28,836	30,830
Inventories	62,318	63,209
Prepaid expenses and other current assets	2,909	2,926
Total current assets	345,564	331,928
Property and equipment, net	66,527	65,359
Long-term investments	5,353	5,361
Goodwill	6,571	6,571
Acquisition-related intangible assets, net	4,540	5,053
Deferred tax assets, net	663	672
Other long-term assets	17,894	16,341
Total assets	447,112	431,285
Current liabilities:
Accounts payable	15,731	13,487
Accrued compensation and related benefits	9,552	9,812
Accrued liabilities	20,040	19,984
Total current liabilities	45,323	43,283
Income tax liabilities	3,114	2,941
Other long-term liabilities	16,689	16,545
Total liabilities	65,126	62,769
Stockholders' equity:
Common stock and additional paid-in capital, $0.001 par value; shares authorized: 150,000; shares issued and outstanding: 40,236 and 39,689 as of March 31, 2016 and December 31, 2015, respectively	276,450	265,763
Retained earnings	103,362	101,287
Accumulated other comprehensive income	2,174	1,466
Total stockholders’ equity	381,986	368,516
Total liabilities and stockholders’ equity	$ 447,112	$ 431,285

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Name:	us-gaap_AccountsPayableCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.