Condensed Consolidated Statement of Changes in Equity - 9 months ended Sep. 30, 2016 - USD ($) $ in Thousands	Total	Total PNMR Common Stockholders’ Equity [Member]	Common Stock [Member]	AOCI [Member]	Retained Earnings [Member]	Non-controlling Interest in Valencia [Member]	Public Service Company of New Mexico [Member]	Public Service Company of New Mexico [Member] Total PNMR Common Stockholders’ Equity [Member]	Public Service Company of New Mexico [Member] Common Stock [Member]	Public Service Company of New Mexico [Member] AOCI [Member]	Public Service Company of New Mexico [Member] Retained Earnings [Member]	Public Service Company of New Mexico [Member] Non-controlling Interest in Valencia [Member]	Texas-New Mexico Power Company [Member]	Texas-New Mexico Power Company [Member] Common Stock [Member]	Texas-New Mexico Power Company [Member] Paid-in Capital [Member]	Texas-New Mexico Power Company [Member] Retained Earnings [Member]
Beginning balance at Dec. 31, 2015	$ 1,726,220	$ 1,654,813	$ 1,166,465	$ (71,432)	$ 559,780	$ 71,407	$ 1,389,340	$ 1,317,933	$ 1,236,776	$ (71,476)	$ 152,633	$ 71,407
Beginning balance TNMP at Dec. 31, 2015	1,654,813						1,317,933						$ 533,380	$ 64	$ 404,166	$ 129,150
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Earnings	103,473	92,436			92,436	11,037	72,342	61,305		0	61,305	11,037
Net earnings	92,040						61,305						31,817			31,817
Total other comprehensive income (loss)	(2,211)	(2,211)		(2,211)			(1,764)	(1,764)		(1,764)	0
Subsidiary preferred stock dividends	(396)	(396)			(396)
Dividends declared on preferred stock							(396)	(396)		0	(396)
Equity contribution from parent							28,142	28,142	28,142				50,000	0	50,000	0
Dividends declared on common stock	(52,571)	(52,571)			(52,571)		(4,142)	(4,142)		0	(4,142)		(17,965)			(17,965)
Proceeds from stock option exercise	6,668	6,668	6,668
Awards of common stock	(14,920)	(14,920)	(14,920)
Excess tax (shortfall) from stock-based payment arrangements	(15)	(15)	(15)
Stock based compensation expense	4,401	4,401	4,401
Valencia’s transactions with its owner	(12,327)					(12,327)	(12,327)					(12,327)
Ending balance at Sep. 30, 2016	1,758,322	$ 1,688,205	$ 1,162,599	$ (73,643)	$ 599,249	$ 70,117	1,471,195	$ 1,401,078	$ 1,264,918	$ (73,240)	$ 209,400	$ 70,117
Ending balance TNMP at Sep. 30, 2016	$ 1,688,205						$ 1,401,078						$ 597,232	$ 64	$ 454,166	$ 143,002