Deferred Tax Assets Not Recognized

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- Definition

Income Taxes [Line Items]

+ References

No definition available.

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- Definition

Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (d)(3)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32718-109319

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

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- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32559-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Carryforwards
-URI http://asc.fasb.org/extlink&oid=6506874

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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=SL6600010-109319

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Income Taxes (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2017	Mar. 31, 2016
Income Taxes [Line Items]
Loss and credit carryforwards from share-based compensation not included in deferred tax assets	$ 153.2
Unrecognized tax benefits that if realized would impact effective tax rate	0.6	$ 0.6
Foreign Tax Authority \| United Kingdom
Income Taxes [Line Items]
Net operating loss carryforwards	0.7
Foreign Tax Authority \| Canada
Income Taxes [Line Items]
Net operating loss carryforwards	3.5
State and Local Jurisdiction
Income Taxes [Line Items]
Net operating loss carryforwards	395.7
Domestic Tax Authority \| United States
Income Taxes [Line Items]
Net operating loss carryforwards	709.9
Credit carryforward	57.5
Maximum
Income Taxes [Line Items]
Decrease in Unrecognized Tax Benefits is Reasonably Possible	$ 14.2