Period end amount of construction work in progress in public utility

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- Definition

The carrying amount of the long-term purchase obligation as of the balance sheet date, which equals the sum of all payments due.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 47
-Paragraph 10
-Subparagraph b

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 47
-Paragraph 6

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- Definition

Gas costs of a regulated entity that are refundable through future rate adjustments. Such costs are a form of a regulatory liabilities and are expected to be refunded in less than one year through rate adjustments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 71
-Paragraph 11

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- Definition

The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 71
-Paragraph 9, 10

+ Details

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- Definition

Discloses the amount of unrecovered costs for purchased gas.

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- Details

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- Details

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Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Jun. 30, 2011	Jun. 30, 2011 Maryland [Member]	Jun. 30, 2011 Maryland [Member] BPO Plan [Member]	Sep. 30, 2010 Maryland [Member] BPO Plan [Member]	Jun. 30, 2011 Virginia [Member]	Mar. 31, 2011 Virginia [Member]	Jun. 30, 2011 Retail Energy Marketing [Member]	Jun. 30, 2011 Capital Energy Ventures Corp.	Jun. 30, 2011 Other Non-Utility [Member]	Jun. 30, 2011 October 31, 2011 [Member]	Jun. 30, 2011 December 31, 2011 [Member]
Commitments and Contingencies [Line Items]
Reserve Margin-Low		5.00%
Reserve Margin-High		6.50%
Requested Increase In Utility Revenue		$ 30.0			$ 28.5	$ 29.6
Requested Overall Rate of Return	8.59%				8.58%
Requested Rate Of Return On Common Equity		10.45%			10.50%
Authorized Overall Rate Of Return		8.20%
Authorized Rate Of Return On Common Equity		10.00%			10.00%
Refundable Gas Costs		2.1
Unrecovered Costs For Purchased Gas Amount					0.5
Recorded Unconditional Purchase Obligation	649.5						558.1	88.4	3.0	53.0	36.0
Approved Recoverable Costs for VA SAVE Plan	116.5
Target Return On Common Equity For PBR Plan	10.50%
Refunded Revenues Excluded From ESM Calculation	2.4
Regulatory Assets			5.8	6.4
Public Utilities Property Plant And Equipment Construction Work In Progress	$ 4.2