XML 109 R82.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Segment Information - Summary of sales by product and service (Details) - item | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Segment Information |  |  |
Number of reportable segments | 1 | 1 | 1
Sales (as a percent) | 100.00% | 100.00% | 100.00%
Carbon steel |  |  |
Segment Information |  |  |
Sales (as a percent) | 52.00% | 53.00% | 52.00%
Aluminum |  |  |
Segment Information |  |  |
Sales (as a percent) | 19.00% | 19.00% | 19.00%
Stainless steel |  |  |
Segment Information |  |  |
Sales (as a percent) | 14.00% | 14.00% | 14.00%
Alloy |  |  |
Segment Information |  |  |
Sales (as a percent) | 6.00% | 6.00% | 6.00%
Toll processing and logistics |  |  |
Segment Information |  |  |
Sales (as a percent) | 4.00% | 4.00% | 4.00%
Other |  |  |
Segment Information |  |  |
Sales (as a percent) | 5.00% | 4.00% | 5.00%

X
- Definition Represents the percentage of revenue from sale of goods and services. + References No definition available. + Details
Name: | rs_SalesRevenueGoodsAndServicesNetPercentage
Namespace Prefix: | rs_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. + References No definition available. + Details
Name: | us-gaap_NumberOfReportableSegments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- 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_SegmentReportingInformationLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | srt_ProductOrServiceAxis=rs_CarbonSteelMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=rs_AluminumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=rs_StainlessSteelMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=rs_AlloySteelMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=rs_TollProcessingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=rs_OtherProductsOrServicesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |