Condensed Consolidated Statements of Comprehensive Income (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Unrealized holding gains (losses) arising during the period, income tax (expense)	$ (290)	$ (3,022)	$ (3,401)	$ (10,437)
Reclassification adjustment for (gains) included in net earnings (loss), income tax expense	2,185	4,992	2,714	8,538
Pension liability adjustment, income tax (expense) benefit	(631)	(476)	(1,262)	(952)
Change in fair market value, income tax (expense)	3	40	(1)	99
Reclassification adjustment for (gains) losses included in net earnings (loss), income tax expense (benefit)	(18)	(16)	(35)	(31)
Public Service Company of New Mexico [Member]
Unrealized holding gains (losses) arising during the period, income tax (expense)	(290)	(3,022)	(3,401)	(10,437)
Reclassification adjustment for (gains) included in net earnings (loss), income tax expense	2,185	4,992	2,714	8,538
Pension liability adjustment, income tax (expense) benefit	(631)	(476)	(1,262)	(952)
Texas-New Mexico Power Company [Member]
Change in fair market value, income tax (expense)	3	40	(1)	99
Reclassification adjustment for (gains) losses included in net earnings (loss), income tax expense (benefit)	$ (18)	$ (16)	$ (35)	$ (31)