Condensed Consolidated Statement of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Treasury Stock	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Apr. 30, 2019	$ 47,100	$ 6,875	$ 3,133	$ (53)	$ 43,552	$ (6,407)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss attributable to Kewaunee Scientific Corporation	471				471
Other comprehensive income (loss)	195					195
Cash dividends paid	(522)				(522)
Stock based compensation	60	9	51
Ending balance at Jul. 31, 2019	47,304	6,884	3,184	(53)	43,501	(6,212)
Beginning balance at Apr. 30, 2019	47,100	6,875	3,133	(53)	43,552	(6,407)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss attributable to Kewaunee Scientific Corporation	(1,707)
Other comprehensive income (loss)	18
Ending balance at Oct. 31, 2019	44,468	6,884	3,226	(53)	40,800	(6,389)
Beginning balance at Jul. 31, 2019	47,304	6,884	3,184	(53)	43,501	(6,212)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss attributable to Kewaunee Scientific Corporation	(2,178)				(2,178)
Other comprehensive income (loss)	(177)					(177)
Cash dividends paid	(523)				(523)
Stock based compensation	42		42
Ending balance at Oct. 31, 2019	44,468	6,884	3,226	(53)	40,800	(6,389)
Beginning balance at Apr. 30, 2020	38,415	6,885	3,360	(53)	37,821	(9,598)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss attributable to Kewaunee Scientific Corporation	(598)				(598)
Other comprehensive income (loss)	(13)					(13)
Stock based compensation	98	20	78
Ending balance at Jul. 31, 2020	37,902	6,905	3,438	(53)	37,223	(9,611)
Beginning balance at Apr. 30, 2020	38,415	6,885	3,360	(53)	37,821	(9,598)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss attributable to Kewaunee Scientific Corporation	(778)
Other comprehensive income (loss)	(48)
Ending balance at Oct. 31, 2020	37,830	6,905	3,581	(53)	37,043	(9,646)
Beginning balance at Jul. 31, 2020	37,902	6,905	3,438	(53)	37,223	(9,611)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss attributable to Kewaunee Scientific Corporation	(180)				(180)
Other comprehensive income (loss)	(35)					(35)
Stock based compensation	143		143
Ending balance at Oct. 31, 2020	$ 37,830	$ 6,905	$ 3,581	$ (53)	$ 37,043	$ (9,646)

Amount of increase to additional paid-in capital (APIC) for recognition of cost for award under share-based payment arrangement.

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