Deferred tax valuation allowance.

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- Definition

Depreciation and Amortization Recorded to Fuel and Other O and M Expense.

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- Definition

Provision For Whole sale Revenue Refunds.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Revenue refunded.

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Balance Type:	credit
Period Type:	duration

- Definition

The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of intangible assets over their estimated remaining economic lives.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Transactions that do not result in cash inflows or outflows in the period in which they occur, but affect net income and thus are removed when calculating net cash flow from operating activities using the indirect cash flow method. This element is used when there is not a more specific and appropriate element.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

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- Definition

The component of interest expense comprised of the periodic charge against earnings over the life of the financing arrangement to which such costs relate.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 8
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 8
-Article 9

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Data Type:	xbrli:monetaryItemType
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- Definition

The expense recognized in the current period that allocates the cost of a tangible asset used in providing revenue generating services over the asset's useful life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

The component of income tax expense for the period representing the net change in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section I
-Subsection 7

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 45
-Subparagraph b

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 289

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph h
-Article 4

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Reductions in the entity's income taxes that arise when compensation cost (from non-qualified share-based compensation) recognized on the entity's tax return exceeds compensation cost from share-based compensation recognized in financial statements. This element reduces net cash provided by operating activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A96

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

- Definition

The difference between the book value and the sale price of other nonspecific investments. This element is used when other, more specific, elements are not appropriate. This element refers to the gain (loss) included in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

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

- Definition

The net change during the reporting period in the aggregate amount of obligations due within one year (or one business cycle). This may include trade payables, amounts due to related parties, royalties payable, and other obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The net change during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

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

- Definition

The net change during the period in the amount of cash payments due to taxing authorities for taxes that are based on the reporting entity's earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The net change during the reporting period in the asset created by the regulatory convention in which costs and revenues associated with certain utility expenses (such as fuel) are accumulated but on which no return is earned.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

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

- Definition

The net change during the reporting period in interest payable, which represents the amount owed to note holders, bond holders, and other parties for interest earned on loans or credit extended to the reporting entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The net change during the reporting period in the aggregate value of all inventory held by the reporting entity, associated with underlying transactions that are classified as operating activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

+ Details

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

- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The net change during the period in the amount of cash payments due to taxing authorities for non-income-related taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

+ Details

Name:	us-gaap_IncreaseDecreaseInPropertyAndOtherTaxesPayable
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The net cash from (used in) all of the entity's operating activities, including those of discontinued operations, of the reporting entity. Operating activities generally involve producing and delivering goods and providing services. Operating activity cash flows include transactions, adjustments, and changes in value that are not defined as investing or financing activities.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- Definition

The net cash from (used in) all of the entity's operating activities, including those of discontinued operations, of the reporting entity. Operating activities include all transactions and events that are not defined as investing or financing activities. Operating activities generally involve producing and delivering goods and providing services. Cash flows from operating activities are generally the cash effects of transactions and other events that enter into the determination of net income.

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

- Definition

The other noncash expense, not otherwise specified in the taxonomy, charged against earnings in the period to allocate the cost of tangible and intangible assets over their remaining economic lives.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of pension and other (such as medical, dental and life insurance) postretirement benefit costs recognized during the period for (1) defined benefit plans (periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain or loss on assets, prior service cost or credit, transition asset or obligation, and gain or loss due to settlements or curtailments) and for (2) defined contribution plans (to the extent that a plan's defined contributions to an individual's account are to be made for periods in which that individual renders services, the net cost for a period shall be the contribution called for in that period; if a plan calls for contributions for periods after an individual retires or terminates, the estimated cost shall be accrued during the employee's service period).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph h

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5, 11

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of cash or cash equivalents contributed by the entity to fund its pension plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

+ Details

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

- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph A1, A4, A5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 5
-Subparagraph b

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 29

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph a

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(1)

+ Details

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

- Definition

Amount of the current period expense charged against operations, the offset which is generally to the allowance for doubtful accounts for the purpose of reducing receivables, including notes receivable, to an amount that approximates their net realizable value (the amount expected to be collected).

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The component of the allowance for funds used during construction during the period based on an assumed rate of return on equity funds used in financing the construction of regulated assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 71
-Paragraph 15

+ Details

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

- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock options, amortization of restricted stock, and adjustment for officers compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

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Supplemental Cash Flow Information (Details) (USD $) In Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2011	Sep. 30, 2010	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Reconciliation of Net Income to Net Cash Flows - Operating Activities follows
Net Income	$ 28,574		$ 25,886	$ 41,990	$ 46,032
Adjustments to Reconcile Net Income To Net Cash Flows from Operating Activities
Depreciation Expense	33,310		32,223	66,100	63,322
Amortization Expense	7,253		7,048	14,631	13,620
Depreciation and amortization recorded to fuel and other O&M expense				2,879	2,586
Amortization of Deferred Debt-Related Costs Included in Interest Expense				2,070	1,773
Provision for Retail Customer Bad Debts				1,289	1,623
Use of Renewable energy Credits for Compliance				3,623
Deferred Income Taxes				32,485	18,266
Deferred Tax Valuation Allowance				(73)	3,214
Pension and Postretirement Expense				10,605	9,751
Pension and Postretirement Funding				(8,932)	(3,529)
Allowance for Equity Funds used During Construction				(2,737)	(1,802)
Share-Based Compensation Expense				1,704	(1,404)
Excess Tax Benefit from Stock Options Exercised				(29)	(826)
CTC Revenue Refunded	(13,000)			(15,112)	(5,339)
Decrease to Reflect PPFAC/PGA Recovery Treatment				(3,008)	(23,058)
Loss on Millenniums Investments					4,135
Changes in Assets and Liabilities which Provided (Used) Cash Exclusive of Changes Shown Separately
Accounts Receivable				(9,572)	(9,430)
Materials And Fuel Inventory				(681)	3,020
Accounts Payable				17,147	6,513
Interest Accrued				(1,360)	1,515
Income Taxes				(8,273)	3,445
Taxes Other Than Income Taxes				453	1,877
Other				3,913	6,878
Net Cash Flows - Operating Activities				149,112	144,990
TEP [Member]
Reconciliation of Net Income to Net Cash Flows - Operating Activities follows
Net Income	25,128	59,673	27,938	29,776	38,396
Adjustments to Reconcile Net Income To Net Cash Flows from Operating Activities
Depreciation Expense	25,850		24,893	51,583	48,953
Amortization Expense	8,180		8,024	16,484	15,810
Depreciation and amortization recorded to fuel and other O&M expense				2,070	1,812
Amortization of Deferred Debt-Related Costs Included in Interest Expense				1,290	996
Provision for Retail Customer Bad Debts				905	1,093
Use of Renewable energy Credits for Compliance				3,355
California power exchange provision for wholesale revenue refunds					2,970
Deferred Income Taxes				24,106	15,452
Pension and Postretirement Expense				9,410	8,653
Pension and Postretirement Funding				(8,168)	(2,973)
Allowance for Equity Funds used During Construction				(2,392)	(1,554)
Share-Based Compensation Expense				1,330	1,088
CTC Revenue Refunded				(15,112)	(5,339)
Decrease to Reflect PPFAC/PGA Recovery Treatment				(7,671)	(10,833)
Changes in Assets and Liabilities which Provided (Used) Cash Exclusive of Changes Shown Separately
Accounts Receivable				(21,954)	(19,851)
Materials And Fuel Inventory				329	1,898
Accounts Payable				24,616	14,216
Interest Accrued				(1,465)	1,529
Income Taxes				(8,292)	6,601
Taxes Other Than Income Taxes				2,822	3,366
Other				3,243	8,286
Net Cash Flows - Operating Activities				$ 106,265	$ 130,569