Subsequent Event (Detail) - Advanced Disposal Services [Member] - Subsequent Event [Member] $ / shares in Units, $ in Billions	Apr. 14, 2019 USD ($) item $ / shares
Subsequent Event [Line Items]
Number of collection operations	94
Number of transfer stations	73
Number of landfills	41
Number of owned or operated recycling facilities	22
Scenario, Forecast [Member]
Subsequent Event [Line Items]
Price per share \| $ / shares	$ 33.15
Total enterprise value \| $	$ 4.9
Advanced Disposal’s net debt \| $	$ 1.9

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

No definition available.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

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-Name Accounting Standards Codification
-Topic 805
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-Section 50
-Paragraph 1
-Subparagraph (b)
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-Section 30
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- Definition

Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6405-128476

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Definition

Represents the number of collection operations.

+ References

No definition available.

+ Details

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Namespace Prefix:	wm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of landfills.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Represents the number of owned or operated recycling facilities.

+ References

No definition available.

+ Details

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- Definition

Represents the number of transfer stations.

+ References

No definition available.

+ Details

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- Details

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