SEGMENT INFORMATION - Schedule of Segment Reporting Information, by Segment (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jan. 26, 2019	Jan. 27, 2018	Jan. 26, 2019	Jan. 27, 2018
Segment Reporting Information [Line Items]
Net Sales	$ 246.9	$ 228.0	$ 734.3	$ 659.3
Income (Loss) from Operations	26.0	35.6	73.8	90.7
Interest Expense, Net	3.2	0.3	5.0	0.3
Other Income, Net	(4.9)	(3.8)	(4.7)	(2.6)
Income before Income Taxes	27.7	39.1	73.5	93.0
Operating Segments
Segment Reporting Information [Line Items]
Net Sales	246.9	228.0	734.3	659.3
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	172.9	184.9	549.8	528.1
Income (Loss) from Operations	27.0	39.4	96.7	118.1
Automotive \| Operating Segments
Segment Reporting Information [Line Items]
Net Sales	174.0	187.7	555.0	535.4
Automotive \| Transfers between Segments
Segment Reporting Information [Line Items]
Net Sales	(1.1)	(2.8)	(5.2)	(7.3)
Industrial
Segment Reporting Information [Line Items]
Net Sales	60.2	25.5	139.8	76.0
Income (Loss) from Operations	8.9	3.2	21.1	8.3
Industrial \| Operating Segments
Segment Reporting Information [Line Items]
Net Sales	60.9	25.5	141.8	75.7
Industrial \| Transfers between Segments
Segment Reporting Information [Line Items]
Net Sales	(0.7)	0.0	(2.0)	0.3
Interface
Segment Reporting Information [Line Items]
Net Sales	13.7	17.6	44.0	55.1
Income (Loss) from Operations	0.0	1.6	0.2	5.0
Interface \| Operating Segments
Segment Reporting Information [Line Items]
Net Sales	13.8	17.7	44.2	55.6
Interface \| Transfers between Segments
Segment Reporting Information [Line Items]
Net Sales	(0.1)	(0.1)	(0.2)	(0.5)
Medical
Segment Reporting Information [Line Items]
Net Sales	0.1	0.1	0.7	0.2
Income (Loss) from Operations	(1.7)	(2.3)	(6.3)	(8.1)
Medical \| Operating Segments
Segment Reporting Information [Line Items]
Net Sales	0.1	0.1	0.7	0.2
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	(0.1)	0.0	(0.1)
Income (Loss) from Operations	(8.2)	(6.3)	(37.9)	(32.6)
Eliminations/Corporate \| Operating Segments
Segment Reporting Information [Line Items]
Net Sales	(1.9)	(3.0)	(7.4)	(7.6)
Eliminations/Corporate \| Transfers between Segments
Segment Reporting Information [Line Items]
Net Sales	$ 1.9	$ 2.9	$ 7.4	$ 7.5

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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