Name:	orly_DebtInstrumentCoverageRatioCovenantMinimum
Namespace Prefix:	orly_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

The maximum consolidated leverage ratio the Company is required to remain below in order to maintain compliance with the covenant clauses of the debt agreement.

No definition available.

Name:	orly_DebtInstrumentLeverageRatioCovenantMaximum
Namespace Prefix:	orly_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

The maximum aggregate amount at any time the credit facility may be increase to at the Company's option.

No definition available.

Name:	orly_LineOfCreditFacilityMaximumAggregateCapacity
Namespace Prefix:	orly_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The maximum aggregate amount the credit facility may be increased by at the Company's option.

No definition available.

Name:	orly_LineOfCreditFacilityMaximumIncrease
Namespace Prefix:	orly_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

A restriction on the borrowing capacity of the line of credit facility. The restriction places a sublimit on the amount that can be borrowed for specific purposes.

No definition available.

Name:	orly_LineOfCreditFacilitySublimit
Namespace Prefix:	orly_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

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

No definition available.

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

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

No definition available.

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

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

No definition available.

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

Date the credit facility first became available, in CCYY-MM-DD format.

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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_LineOfCreditFacilityInitiationDate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

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.

No definition available.

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

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.

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

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

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_UnsecuredDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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

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

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

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