Related-Party Activity (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 29, 2015	Mar. 30, 2014
Related Party Transaction [Line Items]
Product sales to related parties	$ 114feic_SalesRevenueGoodsRelatedParty	$ 1,089feic_SalesRevenueGoodsRelatedParty
Service sales to related parties	360feic_SalesRevenueServicesRelatedParty	261feic_SalesRevenueServicesRelatedParty
Total sales to related parties	474us-gaap_RevenueFromRelatedParties	1,350us-gaap_RevenueFromRelatedParties
Purchases from related parties	700	447
Applied Materials [Member]
Related Party Transaction [Line Items]
Product sales to related parties	87	959
Service sales to related parties	264	168
Lattice Semiconductor [Member]
Related Party Transaction [Line Items]
Service sales to related parties	3	3
Cascade Microtech [Member]
Related Party Transaction [Line Items]
Service sales to related parties	8	8
Oregon Health and Science University [Member]
Related Party Transaction [Line Items]
Product sales to related parties	12	130
Service sales to related parties	85	82
Purchases from related parties	0	39
Electro Scientific Industries [Member]
Related Party Transaction [Line Items]
Product sales to related parties	15	0
TMC BV [Member]
Related Party Transaction [Line Items]
Purchases from related parties	$ 700	$ 408

Product revenues arising from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's' management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

No definition available.

+ Details

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- Definition

Service revenues arising from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's' management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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- Details

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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ References

Reference 1: 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(e))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Related Parties

-URI http://asc.fasb.org/extlink&oid=16382449

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.6-07.1(c))

-URI http://asc.fasb.org/extlink&oid=6488393&loc=d3e606610-122999

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