Business	12 Months Ended
Dec. 31, 2012
Business	1. Business The financial statements presented in this report represent the consolidation of Waste Management, Inc., a Delaware corporation; Waste Management’s wholly-owned and majority-owned subsidiaries; and certain variable interest entities for which Waste Management or its subsidiaries are the primary beneficiary as described in Note 20. Waste Management is a holding company and all operations are conducted by its subsidiaries. When the terms “the Company,” “we,” “us” or “our” are used in this document, those terms refer to Waste Management, Inc., its consolidated subsidiaries and consolidated variable interest entities. When we use the term “WM,” we are referring only to Waste Management, Inc., the parent holding company. We are the leading provider of comprehensive waste management services in North America, including collection, transfer, recycling and resource recovery, and disposal services for residential, commercial, industrial and municipal customers (our “Solid Waste business” or “Solid Waste”). Our Solid Waste business is operated and managed locally by our subsidiaries throughout North America that focus on distinct geographical areas. We are also a leading developer, operator and owner of waste-to-energy and landfill gas-to-energy facilities in the United States. Through the third quarter of 2012, the operations of our local subsidiaries were primarily organized under our Eastern, Midwest, Southern, Western and Wheelabrator operating Groups. In July 2012, we announced a reorganization of our operations, designed to streamline management and staff support and reduce our cost structure, while not disrupting our front-line operations. Principal organizational changes included removing the management layer of our four geographic Groups, each of which previously constituted a reportable segment, and consolidating and reducing the number of geographic Areas from 22 to 17. Following our reorganization, our senior management now evaluates, oversees and manages the financial performance of our Solid Waste business subsidiaries through these 17 Areas. Our reportable segments have been realigned to conform with our new organizational structure. See Note 12 for additional information related to this reorganization. Our Wheelabrator business provides waste-to-energy services and manages waste-to-energy facilities and independent power production plants. We also provide additional services that are not managed through our Solid Waste or Wheelabrator businesses, including our strategic accounts program that expanded with the acquisition of Oakleaf Global Holdings on July 28, 2011 (“Oakleaf”), which are presented in this report as “Other.” Additional information related to our segments and to our acquisition of Oakleaf can be found in Note 21 and in Note 19, respectively.

1. Business

The financial statements presented in this report represent the consolidation of Waste Management, Inc., a Delaware corporation; Waste Management’s wholly-owned and majority-owned subsidiaries; and certain variable interest entities for which Waste Management or its subsidiaries are the primary beneficiary as described in Note 20. Waste Management is a holding company and all operations are conducted by its subsidiaries. When the terms “the Company,” “we,” “us” or “our” are used in this document, those terms refer to Waste Management, Inc., its consolidated subsidiaries and consolidated variable interest entities. When we use the term “WM,” we are referring only to Waste Management, Inc., the parent holding company.

We are the leading provider of comprehensive waste management services in North America, including collection, transfer, recycling and resource recovery, and disposal services for residential, commercial, industrial and municipal customers (our “Solid Waste business” or “Solid Waste”). Our Solid Waste business is operated and managed locally by our subsidiaries throughout North America that focus on distinct geographical areas. We are also a leading developer, operator and owner of waste-to-energy and landfill gas-to-energy facilities in the United States.

Through the third quarter of 2012, the operations of our local subsidiaries were primarily organized under our Eastern, Midwest, Southern, Western and Wheelabrator operating Groups. In July 2012, we announced a reorganization of our operations, designed to streamline management and staff support and reduce our cost structure, while not disrupting our front-line operations. Principal organizational changes included removing the management layer of our four geographic Groups, each of which previously constituted a reportable segment, and consolidating and reducing the number of geographic Areas from 22 to 17.

Following our reorganization, our senior management now evaluates, oversees and manages the financial performance of our Solid Waste business subsidiaries through these 17 Areas. Our reportable segments have been realigned to conform with our new organizational structure. See Note 12 for additional information related to this reorganization. Our Wheelabrator business provides waste-to-energy services and manages waste-to-energy facilities and independent power production plants. We also provide additional services that are not managed through our Solid Waste or Wheelabrator businesses, including our strategic accounts program that expanded with the acquisition of Oakleaf Global Holdings on July 28, 2011 (“Oakleaf”), which are presented in this report as “Other.” Additional information related to our segments and to our acquisition of Oakleaf can be found in Note 21 and in Note 19, respectively.