Maximum borrowing capacity, Term Loan and Line of Credit

No definition available.

Name:	crl_MaximumBorrowingCapacityTermLoanAndLineOfCredit
Namespace Prefix:	crl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number of Quarterly Installment Payments

+ References

No definition available.

+ Details

Name:	crl_NumberofQuarterlyInstallmentPayments
Namespace Prefix:	crl_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- 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

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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

- Definition

Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

+ 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 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

+ Details

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

- Details

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

- Details

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

- Details

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

Subsequent Events (Details) (USD $)	3 Months Ended	12 Months Ended	0 Months Ended
Subsequent Events (Details) (USD $)	Mar. 28, 2015	Dec. 27, 2014	Apr. 22, 2015	Dec. 28, 2013
Subsequent Event [Line Items]
Maximum borrowing capacity, Term Loan and Line of Credit				$ 970,000,000
Term loan facility				420,000,000us-gaap_SecuredLongTermDebt
Multi-currency revolving credit facility				550,000,000
Interest rate in addition to federal funds rate	1.42%	1.42%
Subsequent Event [Member]
Subsequent Event [Line Items]
Maximum borrowing capacity, Term Loan and Line of Credit			1,300,000,000.0
Term loan facility			400,000,000.0
Multi-currency revolving credit facility			900,000,000.0
Number of quarterly installment payments			20
Federal Funds Effective Swap Rate [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Interest rate in addition to federal funds rate			0.50%