Condensed Consolidating Financial Statements (Details 1) (USD $) In Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Condensed Consolidating Statements of Operations
Operating revenues	$ 3,347	$ 3,158	$ 6,450	$ 6,093
Costs and expenses	2,841	2,572	5,517	5,095
Income from operations	506	586	933	998
Other income (expense):
Interest income (expense)	(117)	(114)	(235)	(226)
Equity in subsidiaries, net of taxes	0	0	0	0
Other, net	(8)	(8)	(11)	(6)
Total other income (expense)	(125)	(122)	(246)	(232)
Income before income taxes	381	464	687	766
Provision for (benefit from) income taxes	131	206	241	316
Consolidated net income	250	258	446	450
Less: Net income attributable to noncontrolling interests	13	12	23	22
Net income attributable to Waste Management, Inc.	237	246	423	428
WM [Member]
Condensed Consolidating Statements of Operations
Operating revenues	0	0	0	0
Costs and expenses	0	0	0	0
Income from operations	0	0	0	0
Other income (expense):
Interest income (expense)	(86)	(78)	(171)	(153)
Equity in subsidiaries, net of taxes	290	293	527	521
Other, net	0	0	0	0
Total other income (expense)	204	215	356	368
Income before income taxes	204	215	356	368
Provision for (benefit from) income taxes	(33)	(31)	(67)	(60)
Consolidated net income	237	246	423	428
Less: Net income attributable to noncontrolling interests	0	0	0	0
Net income attributable to Waste Management, Inc.	237	246	423	428
WM Holdings [Member]
Condensed Consolidating Statements of Operations
Operating revenues	0	0	0	0
Costs and expenses	0	0	0	0
Income from operations	0	0	0	0
Other income (expense):
Interest income (expense)	(8)	(9)	(17)	(19)
Equity in subsidiaries, net of taxes	295	299	537	533
Other, net	0	0	0	0
Total other income (expense)	287	290	520	514
Income before income taxes	287	290	520	514
Provision for (benefit from) income taxes	(3)	(3)	(7)	(7)
Consolidated net income	290	293	527	521
Less: Net income attributable to noncontrolling interests	0	0	0	0
Net income attributable to Waste Management, Inc.	290	293	527	521
Non-Guarantor Subsidiaries [Member]
Condensed Consolidating Statements of Operations
Operating revenues	3,347	3,158	6,450	6,093
Costs and expenses	2,841	2,572	5,517	5,095
Income from operations	506	586	933	998
Other income (expense):
Interest income (expense)	(23)	(27)	(47)	(54)
Equity in subsidiaries, net of taxes	0	0	0	0
Other, net	(8)	(8)	(11)	(6)
Total other income (expense)	(31)	(35)	(58)	(60)
Income before income taxes	475	551	875	938
Provision for (benefit from) income taxes	167	240	315	383
Consolidated net income	308	311	560	555
Less: Net income attributable to noncontrolling interests	13	12	23	22
Net income attributable to Waste Management, Inc.	295	299	537	533
Eliminations [Member]
Condensed Consolidating Statements of Operations
Operating revenues	0	0	0	0
Costs and expenses	0	0	0	0
Income from operations	0	0	0	0
Other income (expense):
Interest income (expense)	0	0	0	0
Equity in subsidiaries, net of taxes	(585)	(592)	(1,064)	(1,054)
Other, net	0	0	0	0
Total other income (expense)	(585)	(592)	(1,064)	(1,054)
Income before income taxes	(585)	(592)	(1,064)	(1,054)
Provision for (benefit from) income taxes	0	0	0	0
Consolidated net income	(585)	(592)	(1,064)	(1,054)
Less: Net income attributable to noncontrolling interests	0	0	0	0
Net income attributable to Waste Management, Inc.	$ (585)	$ (592)	$ (1,064)	$ (1,054)