XML 39 R29.htm IDEA: XBRL DOCUMENT
v3.19.2

REVENUE Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018
Disaggregation of Revenue [Line Items] |  |  |  |  |
Accrued sales returns | $ 27 |  | $ 27 |  | $ 29
Accrued sales incentives | $ 54 |  | $ 54 |  | $ 62
Service Revenue [Member] |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |
Percent of Total Company Revenue | 1.00% | 1.00% | 1.00% | 1.00% |

X
- Definition Contract With Customer, Sales Incentive Liability + References No definition available. + Details
Name: | gww_ContractWithCustomerSalesIncentiveLiability
Namespace Prefix: | gww_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Percentage Of Company-Wide Revenue + References No definition available. + Details
Name: | gww_PercentageOfCompanyWideRevenue
Namespace Prefix: | gww_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of liability for consideration received or receivable from customer which is not included in transaction price, when consideration is expected to be refunded to customer. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 55 -Paragraph 27 -URI http://asc.fasb.org/extlink&oid=118944142&loc=SL49130611-203046-203046 + Details
Name: | us-gaap_ContractWithCustomerRefundLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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

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