Landfill Accounting (Details Textual) (USD $) In Thousands, unless otherwise specified	6 Months Ended		12 Months Ended
	Jun. 30, 2012 Landfill	Jun. 30, 2011	Dec. 31, 2012	Dec. 31, 2011
Landfill Accounting (Textual) [Abstract]
Number of landfills owned and operated by company	35
Number of landfills operated under life of site operating agreements	6
Number of landfills operated under limited-term operating agreements	6
Net Book Value Landfill Site Costs	$ 802,032
Number of owned landfills that only accept construction and demolition and other non-putrescible waste	4
Average remaining landfill life based on permitted capacity and projected annual disposal volumes	41 years
Number of owned landfills the company is seeking to expand	5
Number of landfills operated under life-of-site operating agreements that the company is seeking to expand	2
Average remaining landfill life based on permitted capacity, projected annual disposal volumes and probable expansion capacity	48 years
Life of Company's owned landfills and landfills operated under life of site operating agreements min range	6 years
Life of Company's owned landfills and landfills operated under life of site operating agreements max range	202 years
Landfill depletion expense	21,350	19,552
Average rate per ton consumed related to landfill depletion at owned landfills and landfills operated under life of site agreements	3.05	2.94
Number of life-of-site landfills for which the Company is responsible for final capping, closure and post-closure maintenance obligations	5
Discount rate for purposes of computing layers for final capping, closure and post-closure obligations			5.75%	5.75%
Inflation rate for purposes of computing layers for final capping, closure and post-closure obligations			2.50%	2.50%
Accretion expense	1,225	967
Average rate per ton consumed related to final capping, closure and post-closure landfill accretion expense	0.18	0.15
Restricted asset balance for purposes of securing our performance of future final capping, closure and post-closure obligations	$ 28,913