Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Unrealized holding gains (losses) arising during the period, income tax (expense) benefit	$ (1,877)	$ 1,200	$ (1,216)	$ (1,213)
Reclassification adjustment for (gains) included in net earnings, income tax expense	1,985	3,925	3,955	8,838
Pension liability adjustment, income tax expense (benefit)	(537)	(583)	(1,611)	(1,749)
Change in fair market value, income tax (expense) benefit	(172)	276	509	276
Reclassification adjustment for (gains) losses included in net earnings (loss), income tax expense (benefit)	(79)	0	(224)	0
Public Service Company of New Mexico [Member]
Unrealized holding gains (losses) arising during the period, income tax (expense) benefit	(1,877)	1,200	(1,216)	(1,213)
Reclassification adjustment for (gains) included in net earnings, income tax expense	1,985	3,925	3,955	8,838
Pension liability adjustment, income tax expense (benefit)	$ (537)	$ (583)	$ (1,611)	$ (1,749)