CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
CURRENT ASSETS:
Trade receivables, allowances	$ 893	$ 840
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 or Stated Value Per Share
Common stock, shares authorized	100,000,000us-gaap_CommonStockSharesAuthorized	100,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	43,614,000us-gaap_CommonStockSharesIssued	42,846,000us-gaap_CommonStockSharesIssued
Other
OTHER ASSETS:
Intangibles, accumulated amortization	22,480	18,870
Developed technology
OTHER ASSETS:
Intangibles, accumulated amortization	$ 27,982	$ 17,602

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