Pension and Other Postretirement Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2013

Public Service Company of New Mexico [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Net Benefit Costs [Table Text Block]

The following tables present the components of the PNM Plans’ net periodic benefit cost:

	Three Months Ended March 31,
	Pension Plan						OPEB Plan						Executive Retirement Program
	2013			2012			2013			2012			2013		2012
	(In thousands)
Components of Net Periodic
Benefit Cost
Service cost	$	—		$	—		$	65		$	54		$	—	$	—
Interest cost	7,035			8,058			1,028			1,324			180		219
Long-term return on plan assets	(10,482		)	(10,325		)	(1,261		)	(1,225		)	—		—
Amortization of net loss	3,710			2,629			1,061			972			58		21
Amortization of prior service cost	19			79			(336		)	(336		)	—		—
Net periodic benefit cost	$	282		$	441		$	557		$	789		$	238	$	240

Texas-New Mexico Power Company [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Net Benefit Costs [Table Text Block]

The following tables present the components of the TNMP Plans’ net periodic benefit cost (income):

	Three Months Ended March 31,
	Pension Plan						OPEB Plan						Executive Retirement Program
	2013			2012			2013			2012			2013		2012
							(In thousands)
Components of Net Periodic
Benefit Cost (Income)
Service cost	$	—		$	—		$	75		$	61		$	—	$	—
Interest cost	772			909			141			156			9		11
Long-term return on plan assets	(1,212		)	(1,331		)	(126		)	(129		)	—		—
Amortization of net (gain) loss	262			115			—			(52		)	—		—
Amortization of prior service cost	—			—			14			14			—		—
Net Periodic Benefit Cost (Income)	$	(178	)	$	(307	)	$	104		$	50		$	9	$	11