CLOSURE AND POST-CLOSURE LIABILITIES (Tables)

12 Months Ended

Dec. 31, 2015

Asset Retirement Obligation Disclosure [Abstract]

Schedule of Closure and Post-Closure Liabilities

The changes to closure and post-closure liabilities (also referred to as "asset retirement obligations") from January 1, 2014 through December 31, 2015 were as follows (in thousands):

	Landfill Retirement Liability			Non-Landfill Retirement Liability			Total
Balance at January 1, 2014	$	27,604		$	19,481		$	47,085
New asset retirement obligations	3,595			—			3,595
Accretion	2,583			1,875			4,458
Changes in estimates recorded to statement of income	(722		)	73			(649		)
Changes in estimates recorded to balance sheet	(1,304		)	—			(1,304		)
Expenditures	(1,580		)	(546		)	(2,126		)
Currency translation and other	(244		)	(114		)	(358		)
Balance at December 31, 2014	29,932			20,769			50,701
Liabilities assumed in TFI acquisition	—			1,676			1,676
New asset retirement obligations	3,151			—			3,151
Accretion	2,516			2,122			4,638
Changes in estimates recorded to statement of income (loss)	(162		)	205			43
Changes in estimates recorded to balance sheet	2,942			—			2,942
Expenditures	(5,946		)	(177		)	(6,123		)
Currency translation and other	(410		)	(369		)	(779		)
Balance at December 31, 2015	$	32,023		$	24,226		$	56,249

Schedule of Expected Payments Related to Asset Retirement Obligations

Anticipated payments (based on current estimated costs and anticipated timing of necessary regulatory approvals to commence work on closure and post-closure activities) for each of the next five years and thereafter are as follows (in thousands):

Year ending December 31,
2016	$	8,160
2017	9,061
2018	9,001
2019	7,621
2020	3,442
Thereafter	262,365
Undiscounted closure and post-closure liabilities	299,650
Less: Discount at credit-adjusted risk-free rate	(156,145		)
Less: Undiscounted estimated closure and post-closure liabilities relating to airspace not yet consumed	(87,256		)
Present value of closure and post-closure liabilities	$	56,249