Acquisitions Pro forma consolidated operating results, nonrecurring activities (Details) $ in Millions	12 Months Ended
Dec. 31, 2015 USD ($)
Japanese Subsidiary
Business Acquisition, Pro Forma Information, Nonrecurring Activities [Line Items]
Reversal of deferred tax asset valuation allowance	$ 16.2
Gain on foreign currency translation adjustment	12.6
J-Devices
Business Acquisition, Pro Forma Information, Nonrecurring Activities [Line Items]
Business combination, pro forma adjustment, net gain (loss)	$ (13.5)

Business Combination, pro forma adjustment, net gain (loss)

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of foreign currency translation gain (loss) in the disposal group, including discontinued operation, recognized in the statement of income as a result of the sale or complete or substantially complete liquidation of an investment in a foreign entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section 45
-Paragraph 20
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64808268&loc=d3e32211-110900

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- Definition

Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=84176650&loc=d3e32123-109318

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