Investments - Variable Interest Entity (Details) $ in Millions	3 Months Ended
Jun. 30, 2017 USD ($)
Variable Interest Entity
Variable Interest Entity
Funding period for additional research and development	6 years
Amount of financial support provided	$ 5.2
Carrying amount of cash	11.6
Carrying amount of in-process research and development intangible assets	8.9
carrying amount of goodwill	3.4
Carrying amount of preferred stock	8.3
Net loss of consolidation entity	0.7
Privately-held Companies \| Variable Interest Entity
Variable Interest Entity
Investment purchased during the period	7.5
Privately-held Companies \| Other Non-current assets
Variable Interest Entity
Cost method investments, after adjustments for impairment	$ 151.8

Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6872867&loc=d3e40691-111596

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=29638308&loc=d3e40346-111594

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Description of the amount of pre-tax income (loss) derived by the reporting entity from the Variable Interest Entity (VIE).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph d
-URI http://asc.fasb.org/extlink&oid=64801991&loc=d3e5747-111685

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The amount of financial or other support the reporting entity has provided (explicitly or implicitly) to the Variable Interest Entity (VIE) that it was not previously contractually required to provide or that the reporting entity intends to provide, including, for example, situations in which the reporting entity assisted the VIE in obtaining another type of support.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64801991&loc=SL6759159-111685

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The duration of control rights relate to additional research and development funding that we may provide to the other company

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Cost method investments purchased during the period.

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The carrying amount of the consolidated Variable Interest Entity's cash included in the reporting entity's statement of financial position.

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The carrying amount of the consolidated Variable Interest Entity's goodwill included in the reporting entity's statement of financial position.

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The carrying amount of the consolidated Variable Interest Entity's of in-process research and development intangible assets included in the reporting entity's statement of financial position.

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The carrying amount of the consolidated Variable Interest Entity's preferred stock included in the reporting entity's statement of financial position.

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