Net Income Per Share Information (Basic and Diluted Net Income Per Common Share) (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Numerator:
Net income attributable to Waste Connections for basic and diluted earnings per share	$ 60,084	$ 60,706	$ 171,763	$ 146,229
Denominator:
Basic shares outstanding	124,342,493	123,676,936	124,179,478	123,557,317
Dilutive effect of stock options and warrants	62,205	182,175	103,401	192,054
Dilutive effect of restricted stock units	365,283	420,555	495,413	340,051
Diluted shares outstanding	124,769,981	124,279,666	124,778,292	124,089,422