XML 38 R84.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Employee Benefit Plans - Individually Significant (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Multiemployer Plans [Line Items] |  |  |
EIN | 73-1309529 |  |
Company Contributions | $ 52 | $ 47 | $ 47
Multiemployer Plan, Total Individually Significant Pension Plans [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Company Contributions | 36 | 33 | 31
Automotive Industries Pension Plan [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Company Contributions | 1 | 1 | 1
Suburban Teamsters of Northern Illinois Pension Plan [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Company Contributions | 3 | 3 | 3
Western Conference of Teamsters Pension Plan [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Company Contributions | 32 | 29 | 27
Multiemployer Plan, Aggregate Individually Insignificant Pension Plans [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Company Contributions | $ 16 | $ 14 | $ 16

X
- Definition The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation 12B -Number 240 -Section 12 -Subsection b-2 + Details
Name: | dei_EntityTaxIdentificationNumber
Namespace Prefix: | dei_
Data Type: | dei:employerIdItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of contributions made to multiemployer plan by employer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450691-114947 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450702-114947 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
Name: | us-gaap_MultiemployerPlanContributionsByEmployer
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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_MultiemployerPlansLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_MultiemployerPlanNameAxis=wm_MultiemployerPlanTotalIndividuallySignificantPensionPlansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MultiemployerPlanNameAxis=wm_AutomotiveIndustriesPensionPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MultiemployerPlanNameAxis=wm_SuburbanTeamstersOfNorthernIllinoisPensionPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MultiemployerPlanNameAxis=wm_WesternConferenceOfTeamstersPensionPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MultiemployerPlanNameAxis=wm_MultiemployerPlanAggregateIndividuallyInsignificantPensionPlansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |