Restructuring - Reserve Rollforward (Details) $ in Thousands	6 Months Ended
Jun. 30, 2019 USD ($)
Restructuring Reserve [Roll Forward]
Restructuring obligations December 31, 2018	$ 2,816
Charges	258
Cash payments	(754)
Settlement of Rusnano payment derivative	(1,611)
Adoption of ASC 842	(620)
Restructuring obligations June 30, 2019	89
Employee Severance
Restructuring Reserve [Roll Forward]
Restructuring obligations December 31, 2018	436
Charges	88
Cash payments	(523)
Settlement of Rusnano payment derivative	0
Adoption of ASC 842	0
Restructuring obligations June 30, 2019	1
Facilities Consolidation
Restructuring Reserve [Roll Forward]
Restructuring obligations December 31, 2018	769
Charges	0
Cash payments	(90)
Settlement of Rusnano payment derivative	0
Adoption of ASC 842	(620)
Restructuring obligations June 30, 2019	59
Others
Restructuring Reserve [Roll Forward]
Restructuring obligations December 31, 2018	1,611
Charges	170
Cash payments	(141)
Settlement of Rusnano payment derivative	(1,611)
Adoption of ASC 842	0
Restructuring obligations June 30, 2019	$ 29

Restructuring Reserve, Settlement for Derivatives

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- Definition

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

+ References

+ Details

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- Definition

Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(d))
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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-Paragraph 2
-Subparagraph (SAB TOPIC 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

+ Details

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Period Type:	instant

- Definition

Amount of increase (decrease) in the accrual for restructuring costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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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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