Condensed Consolidating Financial Statements - Balance Sheets (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 22	$ 32	$ 39	$ 1,307
Other current assets	2,602	2,344
Total current assets	2,624	2,376
Property and equipment, net	11,559	10,950	10,665
Other assets	7,646	7,533
Total assets	21,829	20,859	20,367
Current liabilities:
Current portion of long-term debt	739	417
Accounts payable and other current liabilities	2,523	2,377
Total current liabilities	3,262	2,794
Long-term debt, less current portion	8,752	8,893
Other liabilities	3,773	3,852
Total liabilities	15,787	15,539
Equity:
Stockholders' equity	6,019	5,297
Noncontrolling interests	23	23
Total equity	6,042	5,320	5,367	5,889
Total liabilities and equity	21,829	20,859
Eliminations [Member]
Current assets:
Investments in affiliates	(45,286)	(40,255)
Advances to affiliates	(15,349)	(13,000)
Total assets	(60,635)	(53,255)
Current liabilities:
Due to affiliates	(21,701)	(18,777)
Total liabilities	(21,701)	(18,777)
Equity:
Stockholders' equity	(45,286)	(40,255)
Advances to affiliates	6,352	5,777
Total equity	(38,934)	(34,478)
Total liabilities and equity	(60,635)	(53,255)
WM [Member] | Reportable Legal Entities [Member]
Current assets:
Cash and cash equivalents				1,235
Other current assets	5	5
Total current assets	5	5
Investments in affiliates	22,393	19,924
Other assets	9	14
Total assets	22,407	19,943
Current liabilities:
Current portion of long-term debt	537	269
Accounts payable and other current liabilities	55	81
Total current liabilities	592	350
Long-term debt, less current portion	6,457	6,229
Due to affiliates	15,404	13,350
Other liabilities	8	16
Total liabilities	22,461	19,945
Equity:
Stockholders' equity	6,019	5,297
Advances to affiliates	(6,073)	(5,299)
Total equity	(54)	(2)
Total liabilities and equity	22,407	19,943
WM Holdings [Member] | Reportable Legal Entities [Member]
Current assets:
Other current assets	5	5
Total current assets	5	5
Investments in affiliates	22,893	20,331
Other assets	31	30
Total assets	22,929	20,366
Current liabilities:
Accounts payable and other current liabilities	9	9
Total current liabilities	9	9
Long-term debt, less current portion	304	304
Due to affiliates	224	128
Total liabilities	537	441
Equity:
Stockholders' equity	22,392	19,925
Total equity	22,392	19,925
Total liabilities and equity	22,929	20,366
Non-Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Current assets:
Cash and cash equivalents	22	32	$ 39	$ 72
Other current assets	2,592	2,334
Total current assets	2,614	2,366
Property and equipment, net	11,559	10,950
Advances to affiliates	15,349	13,000
Other assets	7,606	7,489
Total assets	37,128	33,805
Current liabilities:
Current portion of long-term debt	202	148
Accounts payable and other current liabilities	2,459	2,287
Total current liabilities	2,661	2,435
Long-term debt, less current portion	1,991	2,360
Due to affiliates	6,073	5,299
Other liabilities	3,765	3,836
Total liabilities	14,490	13,930
Equity:
Stockholders' equity	22,894	20,330
Advances to affiliates	(279)	(478)
Noncontrolling interests	23	23
Total equity	22,638	19,875
Total liabilities and equity	$ 37,128	$ 33,805