Average Finance Receivable Term

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Namespace Prefix:	egn
Data Type:	us-types:durationStringItemType
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Period Type:	instant

- Definition

Financing Receivable, Recorded Investment, Average Balance 0 to 60 Days Past Due

+ Details

Name:	egn_FinancingReceivableRecordedInvestmentAverageBalance0To60DaysPastDue
Namespace Prefix:	egn
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ Details

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- Definition

The amount of the recorded investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, accounts receivable (with terms exceeding one year), notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Receivable
-URI http://asc.fasb.org/extlink&oid=6953735

+ Details

Name:	us-gaap_FinancingReceivable
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953423-111524
-Subparagraph (c)(1)

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLosses
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Charge to expense for financing receivables that are expected to be uncollectible.

+ References

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesProvisions
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Financing receivables that are equal to or greater than 90 days past due.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953401-111524

+ Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentEqualToGreaterThan90DaysPastDue
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ Details

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

Financial Instruments (Details) (USD $)	6 Months Ended
Financial Instruments (Details) (USD $)	Jun. 30, 2011	Jun. 30, 2011 Alabama Gas Corporation	Dec. 31, 2010 Alabama Gas Corporation	Jun. 30, 2011 Alabama Gas Corporation Long-term Debt, Including Current Portion, Fair Value, Fair Value Disclosure	Jun. 30, 2011 Alabama Gas Corporation Long-term Debt, Including Current Portion, Carrying Value, Fair Value Disclosure	Jun. 30, 2011 Long-term Debt, Including Current Portion, Fair Value, Fair Value Disclosure	Jun. 30, 2011 Long-term Debt, Including Current Portion, Carrying Value, Fair Value Disclosure
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term Debt, Fair Value				$ 213,900,000	$ 205,500,000	$ 443,400,000	$ 410,500,000
Financing Receivable		9,600,000	8,800,000
Financing Receivable, Recorded Investment, Average Balance 0 to 60 Days Past Due		3,000
Average Finance Receivable Term		up to 60 months
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due		361,000
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for credit losses, beginning balance	447,000
Provision	80,000
Allowance for credit losses, ending balance	$ 527,000