Condensed Consolidating Financial Statements (Details 2) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Cash flows from operating activities:
Consolidated net income	$ 285	$ 258	$ 731	$ 708
Equity in earnings of subsidiaries, net of taxes			0	0
Other adjustments			1,006	945
Net cash provided by (used in) operating activities			1,737	1,653
Cash flows from investing activities:
Acquisitions of businesses, net of cash acquired			(645)	(343)
Capital expenditures			(909)	(737)
Proceeds from divestitures of businesses (net of cash divested) and other sales of assets			22	36
Net receipts from restricted trust and escrow accounts and other, net			(3)	(131)
Net cash provided by (used in) investing activities			(1,535)	(1,175)
Cash flows from financing activities:
New borrowings			1,001	775
Debt repayments			(425)	(932)
Common stock repurchases			(528)	(443)
Cash dividends			(481)	(454)
Exercise of common stock options			40	28
Distributions paid to noncontrolling interests and other			(66)	(43)
(Increase) decrease in intercompany and investments, net			0	0
Net cash provided by (used in) financing activities			(459)	(1,069)
Effect of exchange rate changes on cash and cash equivalents			0	1
Increase (decrease) in cash and cash equivalents			(257)	(590)
Cash and cash equivalents at beginning of period			539	1,140
Cash and cash equivalents at end of period	282	550	282	550
WM [Member]
Cash flows from operating activities:
Consolidated net income	272	244	695	672
Equity in earnings of subsidiaries, net of taxes			(850)	(819)
Other adjustments			8	12
Net cash provided by (used in) operating activities			(147)	(135)
Cash flows from investing activities:
Acquisitions of businesses, net of cash acquired			0	0
Capital expenditures			0	0
Proceeds from divestitures of businesses (net of cash divested) and other sales of assets			0	0
Net receipts from restricted trust and escrow accounts and other, net			(5)	(2)
Net cash provided by (used in) investing activities			(5)	(2)
Cash flows from financing activities:
New borrowings			893	592
Debt repayments			0	(617)
Common stock repurchases			(528)	(443)
Cash dividends			(481)	(454)
Exercise of common stock options			40	28
Distributions paid to noncontrolling interests and other			(10)	(10)
(Increase) decrease in intercompany and investments, net			(43)	405
Net cash provided by (used in) financing activities			(129)	(499)
Effect of exchange rate changes on cash and cash equivalents			0	0
Increase (decrease) in cash and cash equivalents			(281)	(636)
Cash and cash equivalents at beginning of period			465	1,093
Cash and cash equivalents at end of period	184	457	184	457
WM Holdings [Member]
Cash flows from operating activities:
Consolidated net income	323	298	850	819
Equity in earnings of subsidiaries, net of taxes			(865)	(836)
Other adjustments			(11)	(13)
Net cash provided by (used in) operating activities			(26)	(30)
Cash flows from investing activities:
Acquisitions of businesses, net of cash acquired			0	0
Capital expenditures			0	0
Proceeds from divestitures of businesses (net of cash divested) and other sales of assets			0	0
Net receipts from restricted trust and escrow accounts and other, net			0	0
Net cash provided by (used in) investing activities			0	0
Cash flows from financing activities:
New borrowings			0	0
Debt repayments			(147)	(35)
Common stock repurchases			0	0
Cash dividends			0	0
Exercise of common stock options			0	0
Distributions paid to noncontrolling interests and other			0	0
(Increase) decrease in intercompany and investments, net			173	65
Net cash provided by (used in) financing activities			26	30
Effect of exchange rate changes on cash and cash equivalents			0	0
Increase (decrease) in cash and cash equivalents			0	0
Cash and cash equivalents at beginning of period			0	0
Cash and cash equivalents at end of period	0	0	0	0
Non-Guarantor Subsidiaries [Member]
Cash flows from operating activities:
Consolidated net income	341	317	901	872
Equity in earnings of subsidiaries, net of taxes			0	0
Other adjustments			1,009	946
Net cash provided by (used in) operating activities			1,910	1,818
Cash flows from investing activities:
Acquisitions of businesses, net of cash acquired			(645)	(343)
Capital expenditures			(909)	(737)
Proceeds from divestitures of businesses (net of cash divested) and other sales of assets			22	36
Net receipts from restricted trust and escrow accounts and other, net			2	(129)
Net cash provided by (used in) investing activities			(1,530)	(1,173)
Cash flows from financing activities:
New borrowings			108	183
Debt repayments			(278)	(280)
Common stock repurchases			0	0
Cash dividends			0	0
Exercise of common stock options			0	0
Distributions paid to noncontrolling interests and other			(56)	(33)
(Increase) decrease in intercompany and investments, net			(130)	(470)
Net cash provided by (used in) financing activities			(356)	(600)
Effect of exchange rate changes on cash and cash equivalents			0	1
Increase (decrease) in cash and cash equivalents			24	46
Cash and cash equivalents at beginning of period			74	47
Cash and cash equivalents at end of period	98	93	98	93
Eliminations [Member]
Cash flows from operating activities:
Consolidated net income	(651)	(601)	(1,715)	(1,655)
Equity in earnings of subsidiaries, net of taxes			1,715	1,655
Other adjustments			0	0
Net cash provided by (used in) operating activities			0	0
Cash flows from investing activities:
Acquisitions of businesses, net of cash acquired			0	0
Capital expenditures			0	0
Proceeds from divestitures of businesses (net of cash divested) and other sales of assets			0	0
Net receipts from restricted trust and escrow accounts and other, net			0	0
Net cash provided by (used in) investing activities			0	0
Cash flows from financing activities:
New borrowings			0	0
Debt repayments			0	0
Common stock repurchases			0	0
Cash dividends			0	0
Exercise of common stock options			0	0
Distributions paid to noncontrolling interests and other			0	0
(Increase) decrease in intercompany and investments, net			0	0
Net cash provided by (used in) financing activities			0	0
Effect of exchange rate changes on cash and cash equivalents			0	0
Increase (decrease) in cash and cash equivalents			0	0
Cash and cash equivalents at beginning of period			0	0
Cash and cash equivalents at end of period	$ 0	$ 0	$ 0	$ 0