CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
CURRENT ASSETS:
Trade receivables, allowances	$ 1,030	$ 893
STOCKHOLDERS’ EQUITY:
Preferred stock, shares authorized	5,000,000us-gaap_PreferredStockSharesAuthorized	5,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Common stock, par value
Common stock, shares authorized	100,000,000us-gaap_CommonStockSharesAuthorized	100,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	44,003,000us-gaap_CommonStockSharesIssued	43,614,000us-gaap_CommonStockSharesIssued
Other
OTHER ASSETS:
Intangibles, accumulated amortization	23,454	22,480
Developed technology
OTHER ASSETS:
Intangibles, accumulated amortization	$ 30,454	$ 27,982

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