Amount of accounts payable, accruals and other liabilities assumed at the acquisition date.

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Amount of long-term and short-term debt assumed at the acquisition date.

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Amount of other assets acquired at the acquisition date.

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Amount of assets acquired at the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

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-Subparagraph (c)

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

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Significant business acquisitions - Estimated fair values of assets acquired and liabilities assumed (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 01, 2014	Dec. 19, 2013
Business Acquisition [Line Items]
Goodwill	$ 60,714us-gaap_Goodwill	$ 57,011us-gaap_Goodwill	$ 54,523us-gaap_Goodwill
AltaLink [Member]
Business Acquisition [Line Items]
Property, plant and equipment				5,610
Goodwill				1,700
Other assets, including cash and cash equivalents				294
Assets acquired				7,604
Accounts payable, accruals and other liabilities				1,025
Notes payable and other borrowings				3,851
Liabilities assumed				4,876
Net assets acquired				2,728
NV Energy [Member]
Business Acquisition [Line Items]
Property, plant and equipment					9,511
Goodwill					2,369
Other assets, including cash and cash equivalents					2,506
Assets acquired					14,386
Accounts payable, accruals and other liabilities					3,456
Notes payable and other borrowings					5,334
Liabilities assumed					8,790
Net assets acquired					$ 5,596