Segment Information - Schedule of Segment Reporting Information, by Segment (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Oct. 26, 2019	Oct. 27, 2018	Oct. 26, 2019	Oct. 27, 2018
Segment Reporting Information [Line Items]
Net Sales	$ 257.2	$ 264.0	$ 527.4	$ 487.4
Income (Loss) from Operations	30.7	19.1	69.3	47.8
Interest Expense, Net	2.7	1.6	5.6	1.8
Other (Income) Expense, Net	(1.0)	(0.1)	(0.9)	0.2
Income before Income Taxes	29.0	17.6	64.6	45.8
Operating Segments
Segment Reporting Information [Line Items]
Net Sales	257.2	264.0	527.4	487.4
Transfers between Segments
Segment Reporting Information [Line Items]
Net Sales	0.0	0.0	0.0	0.0
Automotive
Segment Reporting Information [Line Items]
Net Sales	180.1	201.6	366.3	376.9
Income (Loss) from Operations	28.9	36.8	62.0	69.7
Automotive \| Operating Segments
Segment Reporting Information [Line Items]
Net Sales	181.3	203.5	368.8	381.0
Automotive \| Transfers between Segments
Segment Reporting Information [Line Items]
Net Sales	(1.2)	(1.9)	(2.5)	(4.1)
Industrial
Segment Reporting Information [Line Items]
Net Sales	64.9	47.4	135.7	79.6
Income (Loss) from Operations	15.1	5.1	31.6	12.2
Industrial \| Operating Segments
Segment Reporting Information [Line Items]
Net Sales	65.4	47.9	137.0	80.9
Industrial \| Transfers between Segments
Segment Reporting Information [Line Items]
Net Sales	(0.5)	(0.5)	(1.3)	(1.3)
Interface
Segment Reporting Information [Line Items]
Net Sales	11.9	14.7	24.8	30.3
Income (Loss) from Operations	(0.2)	(0.6)	0.0	0.2
Interface \| Operating Segments
Segment Reporting Information [Line Items]
Net Sales	12.0	14.7	24.9	30.4
Interface \| Transfers between Segments
Segment Reporting Information [Line Items]
Net Sales	(0.1)	0.0	(0.1)	(0.1)
Medical
Segment Reporting Information [Line Items]
Net Sales	0.3	0.3	0.6	0.6
Income (Loss) from Operations	(1.8)	(2.5)	(3.3)	(4.6)
Medical \| Operating Segments
Segment Reporting Information [Line Items]
Net Sales	0.3	0.3	0.6	0.6
Medical \| Transfers between Segments
Segment Reporting Information [Line Items]
Net Sales	0.0	0.0	0.0	0.0
Eliminations/Corporate
Segment Reporting Information [Line Items]
Net Sales	0.0	0.0	0.0	0.0
Income (Loss) from Operations	(11.3)	(19.7)	(21.0)	(29.7)
Eliminations/Corporate \| Operating Segments
Segment Reporting Information [Line Items]
Net Sales	(1.8)	(2.4)	(3.9)	(5.5)
Eliminations/Corporate \| Transfers between Segments
Segment Reporting Information [Line Items]
Net Sales	$ 1.8	$ 2.4	$ 3.9	$ 5.5

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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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.

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