Investment securities, including securities measured at fair value (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Cost Method Investments	$ 12,688	$ 19,426
Chi Lin Optoelectronics Co Ltd [Member]
Cost Method Investments	625	625
Chi Lin Technology Co Ltd [Member]
Cost Method Investments	432	432
Jetronics International Corp [Member]
Cost Method Investments	1,600	1,600
C Company [Member]
Cost Method Investments	8,962	8,962
Spatial Photonics Inc [Member]
Cost Method Investments	0	6,500
eTurboTouch Technology Inc [Member]
Cost Method Investments	477	715
Oculon Optoelectronics Inc [Member]
Cost Method Investments	309	309
Shinyoptics Corp [Member]
Cost Method Investments	$ 283	$ 283

This item represents the aggregate carrying amount of all cost-method investments as reported on or included in the balance sheet. The original cost of the investments may differ from the aggregate carrying amount disclosed due to various adjustments such as: (i) dividends received in excess of earnings after the date of investment that are considered a return of investment and therefore recorded as reductions to cost of the investment, or (ii) a series of operating losses of an investee or other factors which may indicate that a decrease in value of the investment has occurred which is other than temporary and accordingly such decrease in value has been recognized.

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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+ Details