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Period Type:	duration

Represents the amount outstanding pursuant to an equity commitment.

+ References

No definition available.

+ Details

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Namespace Prefix:	mehc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The aggregate amount committed under the equity funding and contribution agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	mehc_
Data Type:	xbrli:monetaryItemType
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- Definition

Represents the nominal ratings capacity in megawatts.

+ References

No definition available.

+ Details

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- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Interest rate stated in the contractual debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Minimum amount of purchase arrangement maturing in the fourth fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Minimum amount of purchase arrangement maturing in the next fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Minimum amount of purchase arrangement maturing in the second fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Minimum amount of purchase arrangement maturing in the third fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

+ Details

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Commitments and Contingencies - Commitments (Details) (USD $)	Jun. 30, 2013 Solar Star Funding, LLC series A senior secured notes, 5.375%, due june 2016 through june 2035 [Member] Subsidiary Debt [Member]	Jun. 30, 2013 Solar Star Funding [Member]	Jun. 30, 2013 Wind-powered generating facilities [Member] MidAmerican Energy Company [Member] MWs	Jul. 31, 2013 Subsequent Event [Member] Wind-powered generating facilities [Member] MidAmerican Energy Company [Member]	Jul. 31, 2013 Subsequent Event [Member] Multi-value projects [Member] MidAmerican Energy Company [Member]
ContractualObligationFiscalYearMaturityScheduleTable [Line Items]
Par value	$ 1,000,000,000
Debt instrument, interest rate, stated percentage	5.375%
Equity funding and contribution agreement, amount committed		2,750,000,000
Equity commitment, outstanding amount		1,750,000,000
Megawatt nominal ratings			1,050
Purchase obligation				1,100,000,000	342,000,000
Purchase obligation, due in next twelve months				199,000,000	17,000,000
Purchase obligation, due in second year				431,000,000	140,000,000
Purchase obligation, due in third year				490,000,000	149,000,000
Purchase obligation, due in fourth year					$ 36,000,000