Condensed Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) (USD $) In Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Unrealized holding gains arising during the period, income tax (expense)	$ (5,827)	$ 1,280	$ (9,280)	$ 58
Reclassification adjustment for (gains) included in net earnings (loss), income tax expense	7,892	720	9,962	1,330
Pension liability adjustment, income tax (expense) benefit	(425)	0	601	147
Change in fair market value, income tax (expense)	327	1,197	318	(3,859)
Reclassification adjustment for (gains) losses included in net earnings (loss), income tax expense (benefit)	(215)	4,035	(302)	8,227
Public Service Company of New Mexico [Member]
Unrealized holding gains arising during the period, income tax (expense)	(5,827)	1,280	(9,280)	58
Reclassification adjustment for (gains) included in net earnings (loss), income tax expense	7,892	720	9,962	1,330
Pension liability adjustment, income tax (expense) benefit	(423)	0	432	147
Change in fair market value, income tax (expense)	0	(71)	0	(2,767)
Reclassification adjustment for (gains) losses included in net earnings (loss), income tax expense (benefit)	0	2,540	(11)	5,210
Texas-New Mexico Power Company [Member]
Pension liability adjustment, income tax (expense) benefit	(1)	0	170	0
Change in fair market value, income tax (expense)	307	541	272	891
Reclassification adjustment for (gains) losses included in net earnings (loss), income tax expense (benefit)	$ (102)	$ (103)	$ (202)	$ (205)