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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares in Year One

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares in Year Three

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares in Year Two

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No definition available.

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award Options Outstanding Shares Above Entities Stock Price

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No definition available.

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award Options Vested in Period Total Fair Value

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Previously Awarded Restricted Stock Granted, Included in Shares Outstanding, Number

+ References

No definition available.

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- Definition

Share based Compensation, weighted percentage assigned to achieving market targets

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- Definition

Share based Compensation, weighted percentage assigned to achieving performance targets

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- Definition

Share-based compensation arrangement by share-based payment award, Purchase price of common stock

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

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

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No definition available.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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- Definition

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

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No definition available.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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No definition available.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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- Definition

Net number of share options (or share units) granted during the period.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

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

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of share options (or share units) exercised during the current period.

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Stock-Based Compensation - Restricted Stock Awards (Details) - USD ($)			12 Months Ended
	Mar. 02, 2018	Mar. 03, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Feb. 28, 2017	Dec. 31, 2015	Jan. 01, 2015	Mar. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Additional pre tax expense			$ 7,100,000	$ 6,200,000	$ 5,600,000
Chairman, President, and Chief Executive Officer \| Common Stock \| Achieves a specified improvement in total shareholder return at the end of 2016 compared to 2011 and she remains an employee
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Number of shares authorized (in shares)									135,000
Chairman, President, and Chief Executive Officer \| Common Stock \| Achieves Specified Improvement In Total Shareholder Return At End Of 2014 Compared To 2011 And She Remains Employee
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Number of shares authorized (in shares)									35,000
Number of shares approved upon meeting target (in shares)						100,000
Chairman, President, and Chief Executive Officer \| Common Stock \| Achieves a specific performance target by the end of 2019 and she remains an employee
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Number of shares authorized (in shares)							53,859
Chairman, President, and Chief Executive Officer \| Common Stock \| Achieves a specific performance target by the end of 2017 and she remains an employee
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Number of shares authorized (in shares)							17,953
Executive Vice President and Chief Financial Officer \| Common Stock \| Achieved performance target for 2015 and 2016
Restricted Stock
Granted (in shares)	7,670	2,754
Weighted-Average Grant Date Fair Value
Granted (in dollars per share)	$ 35.85	$ 36.30
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Number of shares approved upon meeting target (in shares)						100,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Weighted-average grant date fair value (in dollars per share)	$ 35.85	$ 36.30
Executive Vice President and Chief Financial Officer \| Common Stock \| Achieved performance target for 2015, 2016 and 2017
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Value of stock to be granted if performance targets are achieved								$ 275,000
Restricted Stock
Restricted Stock
Beginning balance (in shares)			189,045
Granted (in shares)			221,062
Exercised (in shares)			(237,402)
Forfeited (in shares)			(6,054)
Ending balance (in shares)			166,651	189,045
Weighted-Average Grant Date Fair Value
Beginning balance (in dollars per share)			$ 31.11
Granted (in dollars per share)			29.65	$ 23.06	$ 26.49
Exercised (in dollars per share)			28.46
Forfeited (in dollars per share)			31.37
Ending balance (in dollars per share)			32.93	31.11
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Weighted-average grant date fair value (in dollars per share)			$ 29.65	$ 23.06	$ 26.49
Total fair value of restricted shares that vested			$ 8,558,000	$ 5,747,000	$ 5,079,000
Stock Options
Stock Options
Beginning balance (in shares)			193,441
Granted (in shares)			0
Exercised (in shares)			(112,441)
Forfeited (in shares)			0
Expired (in shares)			0
Ending balance (in shares)			81,000	193,441
Weighted Average Exercise Price
Beginning balance (in dollars per share)			$ 9.98
Granted (in dollars per share)			0.00
Exercised (in dollars per share)			8.56
Forfeited (in dollars per share)			0.00
Expired (in dollars per share)			0.00
Ending balance (in dollars per share)			$ 11.94	$ 9.98
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Aggregate intrinsic value of stock options outstanding			$ 2,400,000
Weighted average remaining contract life			1 year 15 days
Exercise price of stock options that are greater than the closing price (in shares)			0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Weighted-average grant date fair value options granted (in dollars per share)			$ 0.00	$ 0.00	$ 0.00
Total fair value of options that vested			$ 0	$ 0	$ 0
Total intrinsic value of options exercised			3,117,000	2,234,000	1,242,000
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Additional pre tax expense			$ 1,000,000
Performance Shares \| Executive
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Shares granted (in shares)			97,697
Weighted percentage assigned to achieving market targets			40.00%
Weighted percentage assigned to achieving performance targets			60.00%
Shares excluded (in shares)			47,279
Shares approved, maximum number of shares available in year two (in shares)			130,302
Shares approved, maximum number of shares available in year three (in shares)			146,941
Performance period			3 years
Public Service Company of New Mexico
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Additional pre tax expense			$ 4,900,000	4,400,000	4,200,000
Public Service Company of New Mexico \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Additional pre tax expense			700,000
Texas-New Mexico Power Company
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Additional pre tax expense			2,200,000	$ 1,800,000	$ 1,500,000
Texas-New Mexico Power Company \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Additional pre tax expense			$ 300,000