Long Term Contract For Purchase of Electric Power Fixed Charges

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Long Term Contract for Purchae of Electric Power Variable Charges

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Long term contract option to purchase, approximate approval period

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Long term contract option to purchase, estimated purchase price

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Long term contract option to purchase, number of days to set FMV

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Long term contract option to purchase, ownership percentage

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Long term contract option to purchase, purchase price - percentage of adjusted NBV

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Long term contract option to purchase, purchase price - percentage of FMV

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Number of Mega Watts Purchased

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Operating Leases, Extended Lease Term Option

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Operating Leases, Future Minimum Payments Due, Next Six Months

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Operating leases, future minimum payments due, renewal term

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Operating Leases, Renewal Options After Original Lease Term

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- Definition

Period of Long Term Contract For Purchase of Electric Power Fixed Costs

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Results of Operations Variable Interest Entity Operating Expenses

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Results of Operations Variable Interest Entity Operating Revenues

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- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold, or consumed within one year (or the normal operating cycle, if longer). Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Total obligations incurred as part of normal operations that are expected to be paid during the following twelve months or within one business cycle, if longer.

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The difference between the maximum amount of estimated loss and the amount recorded as of the balance sheet date.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Variable Interest Entities (Details) (USD $)	3 Months Ended
Variable Interest Entities (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Oct. 08, 2013
Variable Interest Entity, Statement Of Operation [Abstract]
Earnings attributable to non-controlling interest	$ 3,380,000	$ 3,531,000
Variable Interest Entity, Consolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Current assets	503,721,000us-gaap_AssetsCurrent		432,817,000us-gaap_AssetsCurrent
Total assets	5,939,339,000us-gaap_Assets	5,507,026,000us-gaap_Assets	5,829,325,000us-gaap_Assets
Current liabilities	693,034,000us-gaap_LiabilitiesCurrent		704,282,000us-gaap_LiabilitiesCurrent
Owners’ equity – non-controlling interest	72,766,000us-gaap_MinorityInterest		73,546,000us-gaap_MinorityInterest
Net earnings	14,340,000us-gaap_NetIncomeLoss	12,468,000us-gaap_NetIncomeLoss
Public Service Company of New Mexico [Member]
Variable Interest Entity, Consolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Operating Leases, Renewal Options After Original Lease Term (in years)	2 years
Operating Leases, Extended Lease Term Option (in years)	6 years
Public Service Company of New Mexico [Member] \| Palo Verde Nuclear Generating Station [Member]
Variable Interest Entity, Consolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Operating Leases, Future Minimum Payments Due, Next Six Months	8,400,000		26,000,000
Public Service Company of New Mexico [Member] \| Palo Verde Nuclear Generating Station [Member] \| Property Lease Guarantee [Member] \| Maximum [Member]
Variable Interest Entity, Consolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Loss Contingency, Range of Possible Loss, Portion Not Accrued	217,300,000.0
Valencia [Member] \| Public Service Company of New Mexico [Member]
Variable Interest Entity [Line Items]
Long Term Contract For Purchase of Electric Power Fixed Costs	4,800,000	4,800,000
Long Term Contract For Purchase of Electric Power Variable Charges	100,000	200,000
Variable Interest Entity, Statement Of Operation [Abstract]
Operating revenues	4,904,000	4,931,000
Operating expenses	(1,524,000)	(1,400,000)
Earnings attributable to non-controlling interest	3,380,000	3,531,000
Variable Interest Entity, Consolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Current assets	2,839,000		2,513,000
Net property, plant, and equipment	71,679,000		72,321,000
Total assets	74,518,000		74,834,000
Current liabilities	1,752,000		1,288,000
Owners’ equity – non-controlling interest	72,766,000		73,546,000
Long term contract option to purchase, ownership percentage	50.00%
Long term contract option to purchase, purchase price - percentage of adjusted NBV	50.00%
Long term contract option to purchase, purchase price - percentage of FMV	50.00%
Long term contract option to purchase, number of days to set FMV	60 days
Long term contract option to purchase, estimated purchase price				85,000,000
Long term contract option to purchase, approximate approval period	15 months
Valencia [Member] \| Public Service Company of New Mexico [Member] \| Purchased Through May 30, 2028 [Member]
Variable Interest Entity [Line Items]
Number of mega watts purchased (in megawatts)	158
Variable Interest Entity, Not Primary Beneficiary [Member] \| Public Service Company of New Mexico [Member]
Variable Interest Entity, Consolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Operating leases, future minimum payments due, renewal term	150,500,000
Delta [Member] \| Public Service Company of New Mexico [Member]
Variable Interest Entity [Line Items]
Long Term Contract For Purchase of Electric Power Fixed Costs		1,600,000
Long Term Contract For Purchase of Electric Power Variable Charges		200,000
Variable Interest Entity, Consolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Period of Long Term Contract For Purchase of Electric Power Fixed Costs	20 years
Delta [Member] \| Public Service Company of New Mexico [Member] \| Delta [Member]
Variable Interest Entity, Consolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Revenues		1,800,000
Net earnings		$ 300,000