This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the cost method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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-Name Accounting Principles Board Opinion (APB)

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-Paragraph 6

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Principles Board Opinion (APB)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

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Percentage of voting equity interests in the investee held by the entity.

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CASH, CASH EQUIVALENTS AND INVESTMENTS (Details 2) (USD $) In Millions, except Per Share data, unless otherwise specified		12 Months Ended		1 Months Ended	12 Months Ended			1 Months Ended	3 Months Ended	1 Months Ended			3 Months Ended						12 Months Ended		1 Months Ended		12 Months Ended
	Dec. 31, 2012	Dec. 31, 2012 Xalted Networks Maximum	Dec. 31, 2011 Xalted Networks Maximum	Mar. 31, 2007 Cortina Cost method investment Series D preferred convertible stock	Dec. 31, 2012 Cortina Cost method investment Series D preferred convertible stock	Dec. 31, 2011 Cortina Cost method investment Series D preferred convertible stock	Dec. 31, 2008 Cortina Cost method investment Series D preferred convertible stock	Oct. 31, 2004 GCT SemiConductor, Inc. Cost method investment Series D preferred convertible stock	Dec. 31, 2012 GCT SemiConductor, Inc. Cost method investment Series D preferred convertible stock	Mar. 31, 2006 Xalted Networks Cost method investment	Aug. 31, 2005 Xalted Networks Cost method investment	May 31, 2005 Xalted Networks Cost method investment	Sep. 30, 2012 Xalted Networks Cost method investment	Dec. 31, 2011 Xalted Networks Cost method investment	Sep. 30, 2009 Xalted Networks Cost method investment	Dec. 31, 2012 SBI Cost method investment	Mar. 31, 2011 SBI Cost method investment	Mar. 31, 2010 SBI Cost method investment	Dec. 31, 2012 SBI Cost method investment	Dec. 31, 2008 SBI Cost method investment	Mar. 31, 2007 ImmenStar, Inc. Cost method investment Series A preferred stock	Sep. 30, 2004 ImmenStar, Inc. Cost method investment Series A preferred stock	Dec. 31, 2008 ImmenStar, Inc. Cost method investment Series A preferred stock	Jun. 30, 2011 Kranem Corporation Xalted Networks
CASH, CASH EQUIVALENTS AND INVESTMENTS
Payments to acquire investments								$ 3.0		$ 0.3	$ 1.0	$ 2.0				$ 0.6	$ 0.7	$ 0.7		$ 0.5		$ 2.0
Shares of preferred stock of Cortina received in exchange for investment in ImmenStar Inc.				3.6			0.4
Per share price of investment	$ 3.09			$ 0.837			$ 0.837
Cash received in exchange for investment																					1.8		0.2
Investment, ownership interest (as a percent)		10.00%	10.00%		1.00%	1.00%		2.00%											2.00%	2.00%
Other-than-temporary impairment charge									$ 2.2				$ 0.8	$ 0.5	$ 1.7
Issued and outstanding stock ownership percentage																								35.00%