Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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-Publisher FASB

-Name Accounting Standards Codification

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-Section 25

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Glossary Investing Activities

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Fair Value of Derivative and Other Financial Instruments, Available for Sale Securities (Details) (PNMR and PNM [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Unrealized gains			$ 37,020		$ 27,156
Available-for-sale securities, Fair value	211,405		211,405		192,511
Proceeds from sales	103,230	90,518	179,336	136,305
Gross realized gains	2,611	6,263	8,962	11,029
Gross realized (losses)	(1,202)	(5,131)	(2,920)	(7,055)
Cash and equivalents [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Unrealized gains			0		0
Available-for-sale securities, Fair value	24,414		24,414		4,628
Domestic value [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Unrealized gains			10,519		5,223
Available-for-sale securities, Fair value	34,967		34,967		30,044
Domestic growth [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Unrealized gains			23,355		15,212
Available-for-sale securities, Fair value	67,527		67,527		51,650
International and other [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Unrealized gains			1,543		247
Available-for-sale securities, Fair value	16,159		16,159		14,868
U.S. Government [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Unrealized gains			262		1,305
Available-for-sale securities, Fair value	16,711		16,711		32,592
Municipals [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Unrealized gains			1,120		4,069
Available-for-sale securities, Fair value	37,074		37,074		43,861
Corporate and other [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Unrealized gains			221		1,100
Available-for-sale securities, Fair value	$ 14,553		$ 14,553		$ 14,868