Income Taxes Accumulated Accrued Interest Receivable (Payable) Related to Income Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
PNMR [Member]
Income Taxes [Line Items]
Accumulated accrued interest receivable	$ 3,236	$ 3,569
Accumulated accrued interest payable	(1,120)	(1,120)
Public Service Company of New Mexico [Member]
Income Taxes [Line Items]
Accumulated accrued interest receivable	3,236	3,569
Accumulated accrued interest payable	(24)	(24)
Texas-New Mexico Power Company [Member]
Income Taxes [Line Items]
Accumulated accrued interest receivable	0	0
Accumulated accrued interest payable	$ (120)	$ (120)