Condensed Consolidated Statements of Cash Flows - TNMP - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net earnings	$ 19,218	$ 21,205
Adjustments to reconcile net earnings to net cash flows from operating activities:
Depreciation and amortization	84,672	78,857
Deferred income tax expense	2,009	1,447
Allowance for equity funds used during construction	(2,668)	(2,621)
Changes in certain assets and liabilities:
Accounts receivable and unbilled revenues	21,169	17,205
Materials, supplies, and fuel stock	(5,183)	4,305
Other current assets	13,079	(18,978)
Other assets	(12,215)	6,561
Accounts payable	(15,905)	(9,647)
Accrued interest and taxes	909	76
Other current liabilities	(6,458)	(4,369)
Other liabilities	(12,263)	(14,050)
Net cash flows from operating activities	116,610	86,477
Cash Flows From Investing Activities:
Utility plant additions	(209,884)	(172,235)
Net cash flows used in investing activities	(211,864)	(174,455)
Cash Flows From Financing Activities:
Revolving credit facilities borrowings, net	23,300	165,500
Transmission interconnection and security deposit arrangements	18,569	5,460
Debt issuance costs and other, net	(431)	(292)
Net cash flows from financing activities	98,539	47,571
Change in Cash, Restricted Cash, and Equivalents	3,285	(40,407)
Cash, Restricted Cash, and Equivalents at Beginning of Period	1,104	47,928
Cash, Restricted Cash, and Equivalents at End of Period	4,389	7,521
Supplemental Cash Flow Disclosures:
Interest paid, net of amounts capitalized	21,682	23,317
Income taxes (refunded), net	(346)	0
Supplemental schedule of noncash investing activities:
Decrease in accrued plant additions	38,918	49,092
Texas-New Mexico Power Company
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net earnings	15,060	8,735
Adjustments to reconcile net earnings to net cash flows from operating activities:
Depreciation and amortization	23,856	22,428
Deferred income tax expense	(345)	(1,471)
Allowance for equity funds used during construction	(374)	(477)
Changes in certain assets and liabilities:
Accounts receivable and unbilled revenues	(1,297)	(286)
Materials, supplies, and fuel stock	(547)	(36)
Other current assets	1,670	1,231
Other assets	(1,329)	1,322
Accounts payable	(3,848)	(3,182)
Accrued interest and taxes	(12,485)	(9,911)
Other current liabilities	(599)	(373)
Other liabilities	(802)	(1,310)
Net cash flows from operating activities	18,960	16,670
Cash Flows From Investing Activities:
Utility plant additions	(100,556)	(76,149)
Net cash flows used in investing activities	(100,556)	(76,149)
Cash Flows From Financing Activities:
Revolving credit facilities borrowings, net	74,600	43,100
Short-term borrowings – affiliate, net	700	0
Transmission interconnection and security deposit arrangements	6,400	1,650
Debt issuance costs and other, net	(104)	(71)
Net cash flows from financing activities	81,596	44,679
Change in Cash, Restricted Cash, and Equivalents	0	(14,800)
Cash, Restricted Cash, and Equivalents at Beginning of Period	0	14,800
Cash, Restricted Cash, and Equivalents at End of Period	0	0
Supplemental Cash Flow Disclosures:
Interest paid, net of amounts capitalized	10,020	9,229
Income taxes (refunded), net	(346)	0
Supplemental schedule of noncash investing activities:
Decrease in accrued plant additions	$ 1,237	$ 13,465