Financing - Long-term Debt Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Long-term Debt, by Maturity [Abstract]
2019	$ 372,302
2020	275,345
2021	606,000
2022	57,000
2023	55,000
Thereafter	1,300,698
Total	2,666,345	$ 2,431,507
PNMR
Long-term Debt, by Maturity [Abstract]
2019	0
2020	140,000
2021	300,000
2022	0
2023	0
Thereafter	0
Total	440,000	300,137
Public Service Company of New Mexico
Long-term Debt, by Maturity [Abstract]
2019	200,000
2020	100,345
2021	306,000
2022	57,000
2023	55,000
Thereafter	947,500
Total	1,665,845	1,665,870
Texas-New Mexico Power Company
Long-term Debt, by Maturity [Abstract]
2019	172,302
2020	35,000
2021	0
2022	0
2023	0
Thereafter	353,198
Total	$ 560,500	$ 465,500

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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