1. Summary of Significant Accounting Policies (Details-Options outstanding) - $ / shares shares in Thousands	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Number of Shares
Outstanding options, beginning balance	12,595
Granted	1,470
Exercised	(619)	(127)
Forfeited	(283)
Outstanding options, ending balance	13,163
Options exercisable at the end of period	8,668
Weighted Average Exercise Price
Outstanding options, beginning balance	$ 4.56
Granted	4.35
Exercised	1.67
Forfeited	5.62
Outstanding options, ending balance	4.65
Options exercisable at the end of period	$ 4.5
Weighted Average Remaining Contractual Term
Weighted Average Remaining Contractual Term, ending	4 years 8 months 12 days
Options exercisable at the end of period	4 years 2 months 27 days

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Weighted Average Exercise Price [Abstract]

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Weighted Average Remaining Contractual Term [Abstract]

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Net number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term of exercisable stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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