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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
Income Taxes (Details) - USD ($) $ in Millions	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Taxes [Abstract]
Effective income tax rate	90.00%		61.00%	68.20%	96.50%
Income Taxes [Abstract]
Impairment charges	$ 3.3		$ 0.0	$ 1.5	$ 0.0
Foreign Jurisdictions [Member]
Income Taxes [Abstract]
Income tax expense (benefit) related to change in deferred tax asset valuation allowance	1.6	$ (4.8)		(3.2)
Valuation allowance	11.4			11.4
U.S. [Member]
Income Taxes [Abstract]
Income tax expense (benefit) related to change in deferred tax asset valuation allowance			$ 6.6		$ 6.6
Valuation allowance	$ 86.0			$ 86.0
Liquid-Cooled Automotive Business [Member]
Income Taxes [Abstract]
Impairment charges		$ (7.4)