Business Segments and Major Customers (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Financial information of business segments
Revenues	$ 62,863	$ 62,527
Gain from settlement		6,200
Segment direct operating income (loss)	40,297	52,848
Operating income (loss)	(17,558)	8,370
Interest and other expense, net	(6,482)	(5,824)
Income (loss)before income taxes	(24,040)	2,546
Semiconductor Business Group (SBG)
Financial information of business segments
Revenues	57,088	62,376
Gain from settlement		6,200
Segment direct operating income (loss)	43,604	56,442
All Other
Financial information of business segments
Revenues	5,775	151
Segment direct operating income (loss)	(3,307)	(3,594)
Reconciling items
Financial information of business segments
Operating income (loss)	$ (57,855)	$ 44,478

Total operating income loss for reporting segments.

No definition available.

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- Definition

The net proceeds or assets obtained in excess of (less than) the net carrying amount of assets recorded, or assets distributed and liabilities assumed less than (in excess of) estimated litigation liability extinguished, in settlement of a litigation matter. Represents (for other than an insurance entity in its normal claims settlement process), the amount of income (expense) recognized in the period to settle pending or threatened litigation and insurance claims.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 9, 10, 11, 12

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

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- Definition

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 5

-Section 03

-Paragraph 10

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- Definition

The net amount of operating interest income (expense).

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 10

-Article 9

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.10)

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The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 5

-Section 03

-Paragraph 1

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

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