Special Charges and Other, Net - Restructuring (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Restructuring Reserve [Roll Forward]
Restructuring reserve, balance	$ 47.2	$ 40.2
Charges	44.2	21.9
Payments	(64.3)	(16.0)
Non-cash - Other	1.4	0.8
Changes in foreign exchange rates	(0.1)	0.3
Restructuring reserve, balance	47.8	47.2
Current	26.9
Non-current	20.9
Employee Separation Costs
Restructuring Reserve [Roll Forward]
Restructuring reserve, balance	0.8	5.4
Charges	48.9	1.2
Payments	(47.1)	(5.9)
Non-cash - Other	0.0	(0.2)
Changes in foreign exchange rates	(0.1)	0.3
Restructuring reserve, balance	12.9	0.8
Exit Costs
Restructuring Reserve [Roll Forward]
Restructuring reserve, balance	27.3	34.8
Charges	(4.7)	0.7
Payments	(13.1)	(9.2)
Non-cash - Other	0.7	1.0
Changes in foreign exchange rates	0.0	0.0
Restructuring reserve, balance	19.2	27.3
Non-Restructuring Exit Costs
Restructuring Reserve [Roll Forward]
Restructuring reserve, balance	19.1	0.0
Charges	0.0	20.0
Payments	(4.1)	(0.9)
Non-cash - Other	0.7	0.0
Changes in foreign exchange rates	0.0	0.0
Restructuring reserve, balance	15.7	$ 19.1
Microsemi Corporation
Restructuring Reserve [Roll Forward]
Additions due to Microsemi acquisition	19.4
Microsemi Corporation \| Employee Separation Costs
Restructuring Reserve [Roll Forward]
Additions due to Microsemi acquisition	10.4
Microsemi Corporation \| Exit Costs
Restructuring Reserve [Roll Forward]
Additions due to Microsemi acquisition	9.0
Microsemi Corporation \| Non-Restructuring Exit Costs
Restructuring Reserve [Roll Forward]
Additions due to Microsemi acquisition	$ 0.0

Restructuring Reserve, Settled Without Cash And Other Adjustments

No definition available.

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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

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-Publisher FASB
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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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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

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- Definition

Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

+ References

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- Definition

Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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Carrying amount as of the balance sheet date of known and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid after one year or beyond the next operating cycle, if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

+ References

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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.

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- Definition

Amount of foreign currency translation gain (loss) which decreases (increases) the restructuring reserve.

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