FAIR VALUE MEASUREMENTS (Detail) - Sure Seal Brand $ in Thousands	3 Months Ended
Jun. 30, 2017 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Balance at April 1, 2017	$ 6,390
Change due to accretion	255
Change in estimate	(255)
Balance at June 30, 2017	$ 6,390

Business combination contingent consideration arrangements change in amount of contingent consideration liability before offset by change in estimate.

No definition available.

+ Details

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Namespace Prefix:	cswi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e7008-128479

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

+ References

No definition available.

+ Details

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- Details

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