Fair Value of Financial Instruments (Narrative) (Detail)	Dec. 31, 2017 $ / gal
Fair Value of Financial Instruments [Abstract]
Minimum range of DOE index curve used in DCF model	2.95
Maximum range of DOE index curve used in DCF model	3.00
Weighted average DOE index curve used in DCF model	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