Goodwill [Abstract]

No definition available.

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- Definition

Note Receivable Resulting From Disposition Of Business

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Amount of liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

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- References

No definition available.

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- Definition

Gain (loss) from sale or disposal of an organization or integrated set of activities (for example, but not limited to, a partnership or corporation) engaged in providing a product or service in a commercial, industrial, or professional environment.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents the cash inflow during the period from the sale of a component of the entity.

+ References

+ Details

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- Details

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Sales of Assets and Business Units, and Goodwill (Details) - USD ($)		1 Months Ended	3 Months Ended	9 Months Ended
	Sep. 30, 2017	Apr. 30, 2016	Jul. 01, 2017	Sep. 30, 2017	Oct. 01, 2016	Apr. 02, 2016
Sales of Assets and Business Units
Note receivable resulting from sale of assets and business units	$ 3,050,000			$ 3,050,000	$ 0
Gain (loss) on sale of assets and business units				(1,496,000)	2,646,000
Proceeds from sale of assets and business units, net of cash sold				967,000	1,972,000
Goodwill [Abstract]
Goodwill impairment				0	$ 0
Goodwill [Roll Forward]
Balance at December 31, 2016				269,758,000
Less: Disposal of relative fair value share in sale of assets in September 2017				(2,244,000)
Balance at September 30, 2017	267,514,000			267,514,000
Silicon Image, Inc
Goodwill [Abstract]
Long-term liabilities from valuation and allocation of purchase price consideration						$ 2,100,000
Hyderabad, India subsidiary and assets related to Simplay Labs testing and certification business \| Disposed of by Sale
Sales of Assets and Business Units
Consideration of disposed group	5,300,000			5,300,000
Cash received from sale of business unit	2,300,000
Note receivable resulting from sale of assets and business units	3,000,000			$ 3,000,000
Gain (loss) on sale of assets and business units	(1,800,000)
Goodwill [Roll Forward]
Less: Disposal of relative fair value share in sale of assets in September 2017	$ (2,200,000)
Hyderabad \| Disposed of by Sale
Sales of Assets and Business Units
Ownership percentage	100.00%			100.00%
Qterics \| Disposed of by Sale
Sales of Assets and Business Units
Gain (loss) on sale of assets and business units		$ 2,600,000
Proceeds from sale of assets and business units, net of cash sold		$ 2,000,000	$ 300,000