Fair Value Measurements (Narrative) (Detail) - $ / gal	Jun. 30, 2018	Dec. 31, 2017
Fair Value [Abstract]
Minimum range of DOE index curve used in DCF model	3.25	2.95
Maximum range of DOE index curve used in DCF model	3.27	3.00
Weighted average DOE index curve used in DCF model	3.26	2.96

Weighted average Doe index curve used in DCF Model.

No definition available.

Name:	wcn_WeightedAverageOfDoeIndexCurveUsedInDcfModel
Namespace Prefix:	wcn_
Data Type:	us-types:perUnitItemType
Balance Type:	na
Period Type:	instant