Financing - Long-term Debt Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Long-term Debt, by Maturity [Abstract]
2016	$ 125,000
2017	57,000
2018	600,025
2019	172,302
2020	100,345
Thereafter	1,031,698
Total	2,086,370	$ 1,955,136
PNMR [Member]
Long-term Debt, by Maturity [Abstract]
2016	0
2017	0
2018	150,000
2019	0
2020	0
Thereafter	0
Total	150,000	118,766
Public Service Company of New Mexico [Member]
Long-term Debt, by Maturity [Abstract]
2016	125,000
2017	57,000
2018	450,025
2019	0
2020	100,345
Thereafter	858,500
Total	1,590,870	1,490,870
Texas-New Mexico Power Company [Member]
Long-term Debt, by Maturity [Abstract]
2016	0
2017	0
2018	0
2019	172,302
2020	0
Thereafter	173,198
Total	$ 345,500	$ 345,500