Segment Reporting - Summary of Revenue Attributable to Services Provided by Company (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Segment Reporting Information [Line Items]
Revenues	$ 143,714	$ 137,279	$ 260,292	$ 250,476
Solid Waste Operations [Member]
Segment Reporting Information [Line Items]
Revenues	107,929	101,311	192,190	182,986
Solid Waste Operations [Member] | Collection [Member]
Segment Reporting Information [Line Items]
Revenues	60,636	58,368	113,962	110,911
Solid Waste Operations [Member] | Disposal [Member]
Segment Reporting Information [Line Items]
Revenues	44,064	38,128	71,831	62,203
Solid Waste Operations [Member] | Power Generation [Member]
Segment Reporting Information [Line Items]
Revenues	1,564	1,998	3,612	5,347
Solid Waste Operations [Member] | Processing [Member]
Segment Reporting Information [Line Items]
Revenues	1,665	2,817	2,785	4,525
Organics [Member]
Segment Reporting Information [Line Items]
Revenues	10,847	10,715	19,867	19,991
Customer Solutions [Member]
Segment Reporting Information [Line Items]
Revenues	13,476	13,274	26,479	25,159
Recycling [Member]
Segment Reporting Information [Line Items]
Revenues	$ 11,462	$ 11,979	$ 21,756	$ 22,340