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, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Numerator:
Net income (loss) attributable to Waste Connections for basic and diluted earnings per share	$ 52,061	$ (257,009)	$ 57,360	$ 51,824	$ 60,762	$ 60,084	$ 62,664	$ 49,015	$ (95,764)	$ 232,525	$ 195,655
Denominator:
Basic shares outstanding									123,491,931	124,215,346	123,597,540
Dilutive effect of stock options and warrants										90,334	186,006
Dilutive effect of restricted stock units										481,741	381,506
Diluted shares outstanding									123,491,931	124,787,421	124,165,052