Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 53,365	$ 59,526
Short-term investments	50,689	50,254
Accounts and notes receivable, net of allowance of $532 and $322 as of March 31, 2016 and December 31, 2015, respectively	29,810	27,701
Inventory, net	20,214	15,763
Prepaid expenses and other current assets	10,338	8,165
Total current assets	164,416	161,409
Property and equipment, net of accumulated depreciation of $36,616 and $36,020 as of March 31, 2016 and December 31, 2015, respectively	22,177	21,848
Deferred income tax assets, net	14,857	13,719
Intangible assets, net	7,431	7,588
Goodwill	9,179	9,596
Long-term investments	10,009	8,525
Other assets	9,039	7,196
Total assets	237,108	229,881
Current liabilities:
Accounts payable	9,486	7,333
Accrued liabilities	12,626	8,643
Current portion of deferred revenue	23,948	20,851
Customer deposits	2,268	1,226
Current portion of notes payable and capital lease payable	75	87
Total current liabilities	48,403	38,140
Deferred revenue, net of current portion	31,496	30,190
Liability for unrecognized tax benefits	1,411	1,315
Long-term deferred compensation	2,508	2,199
Long-term business acquisition contingent consideration	0	952
Long-term portion of notes payable and capital lease payable	64	81
Total liabilities	$ 83,882	$ 72,877
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.00001 par value; 25,000,000 shares authorized; no shares issued and outstanding as of March 31, 2016 and December 31, 2015	$ 0	$ 0
Common stock, $0.00001 par value; 200,000,000 shares authorized; 53,356,116 and 53,692,192 shares issued and outstanding as of March 31, 2016 and December 31, 2015, respectively	1	1
Additional paid-in capital	179,630	178,143
Treasury stock at cost, 18,907,498 and 18,432,158 shares as of March 31, 2016 and December 31, 2015, respectively	(131,163)	(122,201)
Retained earnings	104,441	100,978
Accumulated other comprehensive income	317	83
Total stockholders’ equity	$ 153,226	157,004
Total liabilities and stockholders’ equity		$ 229,881

The aggregate of amounts due from customers or clients, within one year of the balance sheet date (or one operating cycle, if longer), for goods or services that have been delivered or sold in the normal course of business and an amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date within one year of the balance sheet, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection and net of any write-downs taken for collection uncertainty on the part of the holder, respectively.

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Period Type:	instant

- Definition

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).