Amount held in escrow.

No definition available.

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- Definition

Deferred gain on sale of assets that does not qualify for gain recognition as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Escrow Receivable

+ References

No definition available.

+ Details

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- Definition

Indemnification Period

+ References

No definition available.

+ Details

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- Definition

Sale of Assets, Reduction of Purchase Price

+ References

No definition available.

+ Details

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- Definition

In a transaction not treated as a divestiture for accounting purposes and in which the disposed operation is not consolidated for accounting purposes, the aggregate amount of the disposed liabilities that are segregated in the balance sheet.

+ References

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section E

-Paragraph Question 2

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section S99

-Paragraph 5

-Subparagraph (SAB TOPIC 5.E.Q2)

-URI http://asc.fasb.org/extlink&oid=27015204&loc=d3e355146-122828

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- Definition

The gain (loss) resulting from the sale of a disposal group that is not a discontinued operation. It is included in income from continuing operations before income taxes in the income statement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2443-110228

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- Definition

The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

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Description of Business (Sale of Fiber Optics-related Assets) (Details) (USD $)	0 Months Ended	12 Months Ended
	May 07, 2012	Sep. 30, 2013	Dec. 31, 2014	Sep. 30, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Deferred gain associated with sale of assets			$ 3,400,000emkr_DeferredGainOnSaleOfAssets	$ 3,400,000emkr_DeferredGainOnSaleOfAssets
Sumitomo Electric Industries, LTD
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of assets	2,800,000
Indemnification associated with sale of assets (up to $3.4 million)	3,400,000
Indemnification period	2 years
Proceeds from sale of assets	13,100,000
Cash held in escrow	2,600,000
Reduction of purchase price		1,100,000
Escrow Receivable			1,500,000
Sumitomo Electric Industries, LTD \| Indemnification Obligation
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Deferred gain associated with sale of assets			$ 3,400,000