Net Income (Loss) Per Share Information (Basic and Diluted Net Income Per Common Share) (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Numerator:
Net income (loss) attributable to Waste Connections for basic and diluted earnings per share	$ 85,592	$ 88,617	$ 27,489	$ 44,842	$ 52,061	$ (257,009)	$ 57,360	$ 51,824	$ 246,540	$ (95,764)	$ 232,525
Denominator:
Basic shares outstanding									153,550,008	123,491,931	124,215,346
Dilutive effect of stock options and warrants									35,119		90,334
Dilutive effect of restricted stock units									469,204		481,741
Diluted shares outstanding									154,054,331	123,491,931	124,787,421