Net Income Per Share Information (Basic and Diluted Net Income Per Common Share) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Numerator:
Net income attributable to Waste Connections for basic and diluted earnings per share	$ 57,360	$ 62,664	$ 109,184	$ 111,679
Denominator:
Basic shares outstanding	124,079,184	124,230,572	124,044,130	124,096,619
Dilutive effect of stock options and warrants	31,246	110,406	36,507	124,000
Dilutive effect of restricted stock units	241,632	507,373	279,422	560,478
Diluted shares outstanding	124,352,062	124,848,351	124,360,059	124,781,097