Investments and Nonregulated Property, Net (LLC) (Details) (MidAmerican Funding, LLC and Subsidiaries [Domain], USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
MidAmerican Funding, LLC and Subsidiaries [Domain]
Investments and Nonregulated Property, Net [Line Items]
Nuclear decommissioning trust	$ 394	$ 337
Rabbi trusts	177	173
Auction rate securities	23	21
Nonregulated property, net of accumulated depreciation of $11 and $14, respectively	21	22
Other	10	8
Total	625	561
Nonregulated property accumulated depreciation	$ 11	$ 14

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Investments that are intended to be held for longer than one operating cycle, including nuclear decommissioning trust funds, Rabbi trusts funds, marketable securities and other investments not otherwise specified in the taxonomy. This line item also includes the net amount of property, plant and equipment held for nonregulated operations.

+ References

No definition available.

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- Definition

Period end book value of accumulated depreciation and amortization on property, plant and equipment that is held for nonregulated operations or not recoverable through rates for regulated utility operations.

+ References

No definition available.

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- Definition

The net amount at the balance sheet date of property, plant and equipment held for nonregulated operations or not recoverable through rates for regulated utility operations.

+ References

No definition available.

+ Details

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- Definition

Amount of equity securities categorized neither as held-to-maturity nor as trading.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

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-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

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-Name Accounting Standards Codification

-Topic 942

-SubTopic 320

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62557-112803

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- Definition

The fair value of investments held in a trust fund to pay for the costs of decontaminating and decommissioning facilities, whether such amount is presented as a separate caption or as a parenthetical disclosure on the balance sheet. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

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- Definition

This item represents the amount that could be realized under a life insurance contract or contracts owned by the Entity as of the date of the statement of financial position. Such Entity-owned life insurance policies are commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

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-Publisher SEC

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-Number 210

-Section 02

-Paragraph 12

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 325

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- Definition

Other investments not otherwise specified in the taxonomy.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Name Regulation S-X (SX)

-Number 210

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-Paragraph 12

-Article 5

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-Name Regulation S-X (SX)

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-Section 03

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(f,g))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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