Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Current assets
Cash and equivalents	$ 82,110	$ 72,441
Short term investments	74,900	64,940
Accounts receivable, net of allowance for doubtful accounts of $224 in 2015 and $223 in 2014	39,153	29,994
Inventories	30,285	33,875
Prepaid expenses	2,355	2,312
Foreign sales tax receivable	346	598
Deferred income taxes	650	906
Other current assets	1,067	1,160
Total current assets	230,866	206,226
Property and equipment:
Furniture and fixtures	5,182	5,231
Office equipment	10,791	10,751
Property and equipment, gross	15,973	15,982
Accumulated depreciation	(13,204)	(13,157)
Property and equipment, net	2,769	2,825
Goodwill, net of accumulated amortization	21,272	22,208
Intangible assets, net of accumulated amortization	10,662	12,819
Other assets, net of accumulated amortization	5,950	7,260
Total assets	271,519	251,338
Current liabilities
Accounts payable	5,984	10,680
Deferred revenue	18,049	17,830
Accrued wages and payroll taxes	7,372	8,458
Income taxes payable	1,951	1,899
Other accrued expenses	5,004	5,413
Deferred compensation	562	806
Liabilities of discontinued operations	85	111
Total current liabilities	39,007	45,197
Other long-term liabilities	43	55
Deferred income taxes	102	213
Total liabilities	39,152	45,465
Stockholders' equity
Common stock: $.001 par value per share, 75,000 shares authorized; 39,793 and 39,660 shares issued and outstanding at June 30, 2015 and December 31, 2014, respectively	40	40
Preferred stock: 500 shares authorized, none issued and outstanding at June 30, 2015 or December 31, 2014	0	0
Additional paid-in capital	83,720	82,450
Accumulated income	153,371	125,885
Accumulated other comprehensive income	(4,764)	(2,502)
Total stockholders' equity	232,367	205,873
Total liabilities and stockholders' equity	$ 271,519	$ 251,338

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).

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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.