Inventories - Additional Information (Detail) - USD ($)	12 Months Ended
Apr. 30, 2018	Apr. 30, 2017
Inventories [Line Items]
LIFO inventory reserve	$ 887,000	$ 748,000
Increase or decrease in cost of product sales as a result of liquidation of LIFO inventory	139,000	14,000
International Subsidiaries [Member]
Inventories [Line Items]
Inventories measured using FIFO method	$ 1,908,000	$ 2,205,000

Inventories [Line Items]

No definition available.

Name:	kequ_InventoriesLineItems
Namespace Prefix:	kequ_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The effect of liquidating LIFO (last in first out) inventory layers on income.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SAB Topic 11.F)
-URI http://asc.fasb.org/extlink&oid=27011343&loc=d3e100079-122729

+ Details

Name:	us-gaap_EffectOfLIFOInventoryLiquidationOnIncome
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of FIFO (first in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6361739&loc=d3e7789-107766

+ Details

Name:	us-gaap_FIFOInventoryAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(c))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_InventoryLIFOReserve
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	srt_ConsolidatedEntitiesAxis=kequ_ForeignSubsidiariesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: