Represents the reference rate used to compute the variable rate on the debt instrument.

No definition available.

Name:	cmd_DebtInstrumentReferenceRate
Namespace Prefix:	cmd_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the maximum additional borrowing capacity available at the entity's option under the revolving credit facility, subject to the satisfaction of certain conditions precedent.

+ References

No definition available.

+ Details

Name:	cmd_LineOfCreditFacilityMaximumAdditionalBorrowingCapacity
Namespace Prefix:	cmd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the percentage of shares of the foreign subsidiaries of the entity pledged as security under the credit agreement terms.

+ References

No definition available.

+ Details

Name:	cmd_LineOfCreditFacilityPercentageOfSharesOfForeignSubsidiariesPledgedAsSecurity
Namespace Prefix:	cmd_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

No definition available.

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_BaseRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_OtherAssetsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_ForeignLineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LetterOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=cmd_SwingLineLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Financing Arrangements (Details) - USD ($)		2 Months Ended	12 Months Ended
Financing Arrangements (Details) - USD ($)	Mar. 04, 2014	Sep. 28, 2017	Jul. 31, 2017	Jul. 31, 2016
Credit Agreement
Debt Instrument [Line Items]
Fees on unused portion of credit facilities (as a percent)			0.20%
Shares of foreign subsidiaries pledged as security (as a percent)			65.00%
Outstanding borrowings			$ 126,000,000
Credit Agreement \| Minimum
Debt Instrument [Line Items]
Fees on unused portion of credit facilities (as a percent)			0.20%
Credit Agreement \| Maximum
Debt Instrument [Line Items]
Fees on unused portion of credit facilities (as a percent)			0.40%
Credit Agreement \| Lender's base rate
Debt Instrument [Line Items]
Margin on reference rate (as a percent)			0.50%
Reference rate (as a percent)			4.00%
Credit Agreement \| Lender's base rate \| Minimum
Debt Instrument [Line Items]
Margin on reference rate (as a percent)			0.25%
Credit Agreement \| Lender's base rate \| Maximum
Debt Instrument [Line Items]
Margin on reference rate (as a percent)			1.25%
Credit Agreement \| LIBOR
Debt Instrument [Line Items]
Margin on reference rate (as a percent)			1.50%
Credit Agreement \| LIBOR \| Minimum
Debt Instrument [Line Items]
Margin on reference rate (as a percent)			1.25%
Reference rate (as a percent)			1.22%
Credit Agreement \| LIBOR \| Maximum
Debt Instrument [Line Items]
Margin on reference rate (as a percent)			2.25%
Reference rate (as a percent)			1.31%
Credit Agreement \| Other assets
Debt Instrument [Line Items]
Unamortized debt issuance costs			$ 580,000	$ 946,000
Revolving Credit Facility
Debt Instrument [Line Items]
Term of line of credit facility	5 years
Maximum borrowing capacity	$ 250,000,000
Maximum additional borrowing capacity available at the entity's option	100,000,000
Revolving Credit Facility \| Subsequent Events
Debt Instrument [Line Items]
Amount borrowed		$ 61,300,000
Borrowings of foreign currency
Debt Instrument [Line Items]
Maximum borrowing capacity	100,000,000
Letters of credit
Debt Instrument [Line Items]
Maximum borrowing capacity	30,000,000
Swing line loans
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 10,000,000