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Represents the gross amount of loans borrowed by the entity against cash surrender value of certain life insurance policies to pay premiums and accrued interest owed.

No definition available.

Name:	rs_LoansBorrowedAgainstLifeInsurancePolicies
Namespace Prefix:	rs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Represents the fixed interest rate on borrowings against the cash surrender value of certain life insurance policies.

No definition available.

Name:	rs_LoansBorrowedAgainstLifeInsurancePolicyFixedInterestRateUnderCertainLifeInsurancePolicies
Namespace Prefix:	rs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Represents the amount of loans and accrued interest outstanding on life insurance policies.

No definition available.

Name:	rs_LoansOutstandingAgainstLifeInsurancePoliciesIncludingAccruedInterest
Namespace Prefix:	rs_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Represents the premiums and accrued interest on loans outstanding against life insurance policies.

No definition available.

Name:	rs_PremiumsAndAccruedInterestOnLoansBorrowedAgainstLifeInsurancePolicies
Namespace Prefix:	rs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 4
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121566466&loc=d3e6812-107765

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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

Rate of interest credited to policyholder deposits.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121643868&loc=d3e14931-158439

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Data Type:	num:percentItemType
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Name:	dei_LegalEntityAxis=rs_EMJMember
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Name:	rs_CashSurrenderValuePoliciesByBorrowingStatusAxis=rs_CashSurrenderValuePoliciesUnborrowedMember
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