Share-based Compensation Arrangement by Share-based Payment Award, Vesting Rate

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Conversion Ratio

+ References

No definition available.

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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

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

+ References

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- Definition

Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to excess tax benefit for share-based compensation cost.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- 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.

+ References

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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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Stock-Based Compensation - Performance Equity Plan and Accounting for Stock Awards (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2018	Jan. 01, 2017	May 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense for stock-based arrangements	$ 7,100	$ 6,200	$ 5,600
Tax expense (benefit) related to stock compensation awards	4,647	(2,324)	0
Cumulative effect adjustment (Note 9)				$ 0	$ 10,382
Accounting Standards Update 2016-09
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Tax expense (benefit) related to stock compensation awards	1,400	2,300
Retained Earnings
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cumulative effect adjustment (Note 9)		11,200		11,208	$ 10,382
Retained Earnings \| Accounting Standards Update 2016-09
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cumulative effect adjustment (Note 9)		10,400
Restricted Shares and Performance-Based Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 4,000
Period to recognize compensation expense	1 year 5 months 12 days
Public Service Company of New Mexico
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense for stock-based arrangements	$ 4,900	4,400	4,200
Tax expense (benefit) related to stock compensation awards	3,967	(1,708)	0
Public Service Company of New Mexico \| Accounting Standards Update 2016-09
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Tax expense (benefit) related to stock compensation awards	1,000	1,700
Public Service Company of New Mexico \| Retained Earnings
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cumulative effect adjustment (Note 9)				$ 11,208
Texas-New Mexico Power Company
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense for stock-based arrangements	2,200	1,800	1,500
Tax expense (benefit) related to stock compensation awards	735	(616)	$ 0
Texas-New Mexico Power Company \| Accounting Standards Update 2016-09
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Tax expense (benefit) related to stock compensation awards	$ 400	$ 600
Performance Equity Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for awards	3 years
Vesting rate	100.00%
Number of shares authorized (in shares)						13,500,000.0
Charge to share pool for each share awarded	5
Performance Equity Plan \| Nonemployee Members of the Board of Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for awards	1 year