CONDENSED CONSOLIDATED STATEMENTS OF INCOME AND OTHER COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Jul. 28, 2018	Jul. 29, 2017
Income Statement [Abstract]
Net sales	$ 1,336,320	$ 1,304,115
Cost of sales	1,052,657	1,005,067
Gross profit	283,663	299,048
Operating expenses	279,149	242,215
Operating income	4,514	56,833
Other income (expense):
Other income, net	1,253	1,512
Interest expense	(11,221)	(11,203)
Income (loss) before taxes	(5,454)	47,142
Income tax expense (benefit)	(945)	16,295
Net income (loss)	(4,509)	30,847
Net loss attributable to noncontrolling interests	53	0
Net income (loss) attributable to Patterson Companies, Inc.	$ (4,456)	$ 30,847
Earnings (loss) per share attributable to Patterson Companies, Inc.:
Basic (in USD per share)	$ (0.05)	$ 0.33
Diluted (in USD per share)	$ (0.05)	$ 0.33
Weighted average shares:
Basic (in shares)	92,529	93,350
Diluted (in shares)	92,529	94,019
Dividends declared per common share (in USD per share)	$ 0.26000	$ 0.26000
Comprehensive income (loss)
Foreign currency translation gain (loss)	$ (9,320)	$ 12,084
Cash flow hedges, net of tax	549	437
Comprehensive income (loss)	$ (13,280)	$ 43,368