Condensed Consolidating Financial Statements - Condensed Consolidating Balance Sheets (Detail) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 39	$ 1,307	$ 58	$ 194
Other current assets	2,306	2,219
Total current assets	2,345	3,526
Property and equipment, net	10,665	10,657	12,344
Other assets	7,409	7,114
Total assets	20,419	21,297	22,490
Current liabilities:
Current portion of long-term debt	253	1,090
Accounts payable and other current liabilities	2,257	2,395
Total current liabilities	2,510	3,485
Long-term debt, less current portion	8,728	8,345
Other liabilities	3,814	3,578
Total liabilities	15,052	15,408
Equity:
Stockholders' equity	5,345	5,866
Noncontrolling interests	22	23
Total equity	5,367	5,889	6,002	6,675
Total liabilities and equity	20,419	21,297
Eliminations [Member]
Current assets:
Investments in and advances to affiliates	(44,833)	(41,839)
Total assets	(44,833)	(41,839)
Current liabilities:
Due to affiliates	(7,365)	(6,745)
Total liabilities	(7,365)	(6,745)
Equity:
Stockholders' equity	(37,468)	(35,094)
Total equity	(37,468)	(35,094)
Total liabilities and equity	(44,833)	(41,839)
WM [Member]
Current assets:
Cash and cash equivalents		1,235		60
Other current assets	3	5
Total current assets	3	1,240
Investments in and advances to affiliates	18,557	17,312
Other assets	55	50
Total assets	18,615	18,602
Current liabilities:
Current portion of long-term debt	41	957
Accounts payable and other current liabilities	83	86
Total current liabilities	124	1,043
Long-term debt, less current portion	5,833	4,958
Due to affiliates	7,289	6,703
Other liabilities	24	32
Total liabilities	13,270	12,736
Equity:
Stockholders' equity	5,345	5,866
Total equity	5,345	5,866
Total liabilities and equity	18,615	18,602
WM Holdings [Member]
Current assets:
Other current assets	6	6
Total current assets	6	6
Investments in and advances to affiliates	18,911	17,782
Other assets	29	28
Total assets	18,946	17,816
Current liabilities:
Accounts payable and other current liabilities	9	13
Total current liabilities	9	13
Long-term debt, less current portion	304	449
Due to affiliates	76	42
Total liabilities	389	504
Equity:
Stockholders' equity	18,557	17,312
Total equity	18,557	17,312
Total liabilities and equity	18,946	17,816
Non-Guarantor Subsidiaries [Member]
Current assets:
Cash and cash equivalents	39	72	$ 58	$ 134
Other current assets	2,297	2,208
Total current assets	2,336	2,280
Property and equipment, net	10,665	10,657
Investments in and advances to affiliates	7,365	6,745
Other assets	7,325	7,036
Total assets	27,691	26,718
Current liabilities:
Current portion of long-term debt	212	133
Accounts payable and other current liabilities	2,165	2,296
Total current liabilities	2,377	2,429
Long-term debt, less current portion	2,591	2,938
Other liabilities	3,790	3,546
Total liabilities	8,758	8,913
Equity:
Stockholders' equity	18,911	17,782
Noncontrolling interests	22	23
Total equity	18,933	17,805
Total liabilities and equity	$ 27,691	$ 26,718