Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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- Definition

This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the cost method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 325

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6872867&loc=d3e40691-111596

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- Definition

This item represents the gain (loss) realized during the period from the sale of investments accounted for under the cost method of accounting and any losses recognized thereon for impairments of other than a temporary nature.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 9

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7(c),9(a))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph c, d

-Article 5

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- Definition

This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 35

-Paragraph 32

-URI http://asc.fasb.org/extlink&oid=7658923&loc=d3e32787-111569

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- Definition

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2443-110228

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- Definition

Gain (loss) from sale or disposal of an organization or integrated set of activities (for example, but not limited to, a partnership or corporation) engaged in providing a product or service in a commercial, industrial, or professional environment.

+ References

No definition available.

+ Details

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13854-109267

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266

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-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

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- Definition

The expense recorded to reduce the value of oil and gas assets consisting of proved properties and unproved properties as the estimate of future successful production from these properties is reduced.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 360

-Section 35

-Paragraph 11

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-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2921-110230

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- Definition

This element represents the cash inflow during the period from the sale of a component of the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

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The aggregate amount of asset impairment charges other than goodwill impairment, gains and losses related to the divestiture of businesses, and unusual items incurred during an accounting period. Generally, these items are either unusual or infrequent, but not both (in which case they would be extraordinary items).

+ References

No definition available.

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Asset Impairments and Unusual Items - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended			3 Months Ended
	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2014	Jun. 30, 2013
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Goodwill impairment charges		$ 10us-gaap_GoodwillImpairmentLoss	$ 509us-gaap_GoodwillImpairmentLoss	$ 4us-gaap_GoodwillImpairmentLoss
(Income) expense from divestitures, asset impairments (other than goodwill) and unusual items		(170)	464	79
Gain (loss) on sale of business		515us-gaap_GainLossOnSaleOfBusiness
Asset impairments (other than goodwill)		345us-gaap_AssetImpairmentCharges	472us-gaap_AssetImpairmentCharges	79us-gaap_AssetImpairmentCharges
(Income) expense from divestitures		515us-gaap_GainLossOnDispositionOfAssets1	8us-gaap_GainLossOnDispositionOfAssets1
Impairment charge from equity method investment				10
Proceeds from divestitures of businesses and other assets (net of cash divested)	155
Landfill [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Number of facilities impaired			2
Waste-to-Energy Facility [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Asset impairments (other than goodwill)			144		130
Number of facilities impaired			3
Recycling Operations [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Goodwill impairment charges		10
Oil and Gas Well [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Impairment of oil and gas property to its estimated fair value			15			272
Recycling Assets [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Asset impairments (other than goodwill)			31
Investment in waste diversion technology company [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Asset impairments (other than goodwill)				20
Majority-owned waste diversion technology company [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Goodwill impairment charges			9
Asset impairments (other than goodwill)			20
Eastern Canada Area [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Gain (loss) on sale of business		18
Eastern Canada Area [Member] \| Landfill [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Asset impairments (other than goodwill)			262		262
Number of facilities impaired			2
Other [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Goodwill impairment charges		10	16
Cost-method Investments, Realized Gain (Loss)							4
Other [Member] \| Medical Waste Facilities [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Asset impairments (other than goodwill)				45
Number of facilities impaired				3
Waste Diversion Technology, Renewable Energy, Recycling, and Medical Waste Operations [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Asset impairments (other than goodwill)		73
Impairment charge relating to decline in value of investment accounted under cost method		22	71	16
Wheelabrator [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Goodwill impairment charges			483		483
Gain (loss) on sale of business		519				519
Puerto Rico [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Goodwill impairment charges			10
Non Solid Waste Operations [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Goodwill impairment charges				4
Puerto Rico Operation and Certain Other Collection and Landfill Assets [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Gain (loss) on sale of business		25
Waste Diversion Technology Companies [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Impairment charge from equity method investment		$ 11