Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 28,038	$ 40,651
Short-term investments	33,796	48,415
Accounts and notes receivable, net of allowance of $590 and $443 as of June 30, 2017 and December 31, 2016, respectively	45,428	39,466
Inventory	60,743	34,841
Prepaid expenses and other current assets	22,949	13,858
Total current assets	190,954	177,231
Property and equipment, net of accumulated depreciation of $34,569 and $37,799 as of June 30, 2017 and December 31, 2016, respectively	29,603	24,004
Deferred income tax assets, net	20,264	19,515
Intangible assets, net	19,334	15,218
Goodwill	13,183	10,442
Long-term investments	0	234
Long-term accounts and notes receivable, net of current portion	27,791	17,602
Other assets	15,182	13,917
Total assets	316,311	278,163
Current liabilities:
Accounts payable	17,993	10,736
Accrued liabilities	19,879	18,248
Current portion of deferred revenue	52,562	45,137
Customer deposits	2,221	2,148
Current portion of business acquisition contingent consideration	1,720	1,690
Other current liabilities	469	80
Total current liabilities	94,844	78,039
Deferred revenue, net of current portion	47,608	40,054
Liability for unrecognized tax benefits	2,179	1,896
Long-term deferred compensation	3,655	3,362
Business acquisition contingent consideration, net of current portion	2,689	1,635
Other long-term liabilities	1,875	2,289
Total liabilities	152,850	127,275
Commitments and contingencies (Note 11)
Stockholders’ equity:
Preferred stock, $0.00001 par value; 25,000,000 shares authorized; no shares issued and outstanding as of June 30, 2017 and December 31, 2016	0	0
Common stock, $0.00001 par value; 200,000,000 shares authorized; 52,808,919 and 52,325,251 shares issued and outstanding as of June 30, 2017 and December 31, 2016, respectively	1	1
Additional paid-in capital	194,221	187,656
Treasury stock at cost, 20,220,227 shares as of June 30, 2017 and December 31, 2016	(155,947)	(155,947)
Retained earnings	124,834	118,275
Accumulated other comprehensive income	352	903
Total stockholders’ equity	163,461	150,888
Total liabilities and stockholders’ equity	$ 316,311	$ 278,163

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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- 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).