XML 26 R55.htm IDEA: XBRL DOCUMENT v2.4.0.8
Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2013
site
Dec. 31, 2012
Dec. 31, 2011
Significant Accounting Policies [Line Items]      
Required Period to Maintain and Monitor Landfill Sites 30-year    
Inflation rate 2.50% 2.50% 2.50%
Credit adjusted, risk free discount rate applicable to asset retirement obligations, lower range 4.25%    
Credit adjusted, risk free discount rate applicable to asset retirement obligations, upper range 8.00%    
Expected credit adjusted, risk free discount rate applied to liabilities incurred 4.75%    
Description of sites with expansion Of the 25 landfill sites with expansions included at December 31, 2013, seven landfills required the Chief Financial Officer to approve the inclusion of the unpermitted airspace. Three of these landfills required approval by our Chief Financial Officer because of community or political opposition that could impede the expansion process. The remaining four landfills required approval due to local zoning restrictions or because the permit application processes do not meet the one- or five-year requirements.    
Number of landfills sites with expansion 25    
Number of landfill sites with expansions that require the principal financial officer to approve the inclusion of the unpermitted airspace 7    
Number of landfill sites with expansions that require the principal financial officer to approve the inclusion of the unpermitted airspace because of community or political opposition 3    
Number of landfill sites with expansions that require the principal financial officer to approve the inclusion of the unpermitted airspace due to permit application processes 4    
Requirements for permit application processes One- or five-year    
Environmental remediation reasonably possible additional losses high estimate $ 190    
Aggregate potential remediation liability 227    
Environmental remediation liabilities that have never been subject to inflation or discounting 36 32  
Increase (decrease) in environmental remediation liabilities due to the impacts of inflation and discounting 7 (11)  
Other intangible assets, amortization method 150% declining balance approach or a straight-line basis    
Restricted trust and escrow accounts 167 138  
Total interest costs 500 509 503
Total capitalized interest costs 19 21 22
Non-cash proceeds from tax-exempt borrowings, net of principal payments 99   100
Customer contracts and customer lists [Member] | Minimum [Member]
     
Significant Accounting Policies [Line Items]      
Amortizable period of the intangible assets 10 years    
Customer contracts and customer lists [Member] | Maximum [Member]
     
Significant Accounting Policies [Line Items]      
Amortizable period of the intangible assets 15 years    
Non-compete covenant [Member] | Minimum [Member]
     
Significant Accounting Policies [Line Items]      
Amortizable period of the intangible assets 2 years    
Non-compete covenant [Member] | Maximum [Member]
     
Significant Accounting Policies [Line Items]      
Amortizable period of the intangible assets 5 years    
Software and Software Development Costs [Member]
     
Significant Accounting Policies [Line Items]      
Capitalized software costs, net of accumulated depreciation 129 123  
Costs incurred for software under development 11 36  
Landfills [Member]
     
Significant Accounting Policies [Line Items]      
Net recorded capitalized asset cost of certain landfills which have ceased accepting waste 261    
Impairment charges recognized $ 262    
Landfills [Member] | Eastern Canada Area [Member]
     
Significant Accounting Policies [Line Items]      
Number of properties associated with impairment charges 2    
Concentration of Credit Risk [Member]
     
Significant Accounting Policies [Line Items]      
Maximum accounts receivable from single customer in percentage to total accounts receivable 5.00% 5.00%