TXNM Energy (TXNM) 10-Q 30 Apr 21 2021 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Mar. 31, 2021	Apr. 23, 2021
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2021
Entity Registrant Name	PNM Resources, Inc.
Entity Incorporation, State or Country Code	NM
Entity Address, Address Line One	414 Silver Ave. SW
Entity Address, City or Town	Albuquerque
Entity Address, State or Province	NM
Entity Address, Postal Zip Code	87102-3289
City Area Code	505
Local Phone Number	241-2700
Entity File Number	001-32462
Entity Tax Identification Number	85-0468296
Title of 12(b) Security	Common Stock, no par value
Trading Symbol	PNM
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		85,834,874
Entity Central Index Key	0001108426
Document Fiscal Year Focus	2021
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	Q1
Amendment Flag	false
Document Transition Report	false
PNM
Document Information [Line Items]
Entity Registrant Name	Public Service Company of New Mexico
Entity Address, Address Line One	414 Silver Ave. SW
Entity Address, City or Town	Albuquerque
Entity Address, State or Province	NM
Entity Address, Postal Zip Code	87102-3289
City Area Code	505
Local Phone Number	241-2700
Entity File Number	001-06986
Entity Tax Identification Number	85-0019030
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding (in shares)		39,117,799
Entity Central Index Key	0000081023
Current Fiscal Year End Date	--12-31
Texas-New Mexico Power Company
Document Information [Line Items]
Entity Registrant Name	Texas-New Mexico Power Company
Entity Address, Address Line One	577 N. Garden Ridge Blvd.
Entity Address, City or Town	Lewisville
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	75067
City Area Code	972
Local Phone Number	420-4189
Entity File Number	002-97230
Entity Tax Identification Number	75-0204070
Entity Current Reporting Status	No
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding (in shares)		6,358
Entity Central Index Key	0000022767
Current Fiscal Year End Date	--12-31

Condensed Consolidated Statemen

Condensed Consolidated Statements of Earnings (Loss) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Electric Operating Revenues:
Contracts with customers	$ 346,585	$ 322,983
Alternative revenue programs	(909)	426
Other electric operating revenue	19,031	10,213
Total electric operating revenues	364,707	333,622
Operating Expenses:
Administrative and general	59,465	46,032
Depreciation and amortization	69,874	68,973
Transmission and distribution costs	17,317	17,286
Taxes other than income taxes	22,593	21,265
Total operating expenses	321,541	285,884
Operating income	43,166	47,738
Other Income and Deductions:
Interest income	3,559	3,423
Gains on investment securities	968	(32,849)
Other income	4,252	2,316
Other (deductions)	(3,290)	(3,473)
Net other income and deductions	5,489	(30,583)
Interest Charges	25,884	30,434
Earnings (Loss) before Income Taxes	22,771	(13,279)
Income Taxes (Benefits)	1,566	(1,880)
Net Earnings (Loss)	21,205	(11,399)
(Earnings) Attributable to Valencia Non-controlling Interest	(3,494)	(3,729)
Preferred Stock Dividend Requirements of Subsidiary	(132)	(132)
Net Earnings (Loss) Available for PNM Common Stock	$ 17,579	$ (15,260)
Net Earnings (Loss) Attributable to PNMR per Common Share:
Basic (dollars per share)	$ 0.20	$ (0.19)
Diluted (dollars per share)	0.20	(0.19)
Dividends Declared per Common Share (dollars per share)	$ 0.3275	$ 0.3075
Cost of energy
Electric Operating Revenues:
Total electric operating revenues	$ 364,707	$ 333,622
Operating Expenses:
Energy costs	115,396	98,710
Energy production costs
Operating Expenses:
Energy costs	36,896	33,618
PNM
Electric Operating Revenues:
Contracts with customers	251,206	235,759
Alternative revenue programs	976	2,161
Other electric operating revenue	19,031	10,213
Total electric operating revenues	271,213	248,133
Operating Expenses:
Administrative and general	47,134	41,668
Depreciation and amortization	41,949	41,449
Transmission and distribution costs	10,659	10,915
Taxes other than income taxes	12,639	12,354
Total operating expenses	238,163	214,528
Operating income	33,050	33,605
Other Income and Deductions:
Interest income	3,595	3,496
Gains on investment securities	968	(32,849)
Other income	2,708	1,509
Other (deductions)	(2,432)	(2,687)
Net other income and deductions	4,839	(30,531)
Interest Charges	12,893	17,629
Earnings (Loss) before Income Taxes	24,996	(14,555)
Income Taxes (Benefits)	2,834	(2,359)
Net Earnings (Loss)	22,162	(12,196)
(Earnings) Attributable to Valencia Non-controlling Interest	(3,494)	(3,729)
Preferred Stock Dividend Requirements of Subsidiary	(132)	(132)
Net Earnings (Loss) Attributable to PNMR	18,668	(15,925)
Net Earnings (Loss) Available for PNM Common Stock	18,536	(16,057)
PNM | Cost of energy
Operating Expenses:
Energy costs	88,886	74,524
PNM | Energy production costs
Operating Expenses:
Energy costs	36,896	33,618
Texas-New Mexico Power Company
Electric Operating Revenues:
Contracts with customers	95,379	87,224
Alternative revenue programs	(1,885)	(1,735)
Other electric operating revenue	0	0
Total electric operating revenues	93,494	85,489
Operating Expenses:
Administrative and general	12,230	10,773
Depreciation and amortization	22,190	21,836
Transmission and distribution costs	6,658	6,371
Taxes other than income taxes	8,881	7,978
Total operating expenses	76,469	71,144
Operating income	17,025	14,345
Other Income and Deductions:
Other income	1,386	670
Other (deductions)	(324)	(109)
Net other income and deductions	1,062	561
Interest Charges	8,475	7,172
Earnings (Loss) before Income Taxes	9,612	7,734
Income Taxes (Benefits)	877	642
Net Earnings (Loss) Attributable to PNMR	8,735	7,092
Texas-New Mexico Power Company | Cost of energy
Operating Expenses:
Energy costs	$ 26,510	$ 24,186

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Net Earnings (Loss)	$ 21,205	$ (11,399)
Unrealized Gains on Available-for-Sale Debt Securities:
Unrealized holding gains arising during the period, net of income tax (expense)	(2,481)	(3,195)
Reclassification adjustment for (gains) included in net earnings, net of income tax expense	(2,699)	(884)
Pension Liability Adjustment:
Reclassification adjustment for amortization of experience (gains) losses recognized as net periodic benefit cost, net of income tax expense (benefit)	1,557	1,548
Fair Value Adjustment for Cash Flow Hedges:
Change in fair market value, net of income tax (expense) benefit of $(317) and $507	930	(1,491)
Reclassification adjustment for (gains) losses included in net earnings, net of income tax expense (benefit) of $158 and $10	(466)	(28)
Total Other Comprehensive Income (Loss)	(3,159)	(4,050)
Comprehensive Income (Loss)	18,046	(15,449)
Comprehensive (Income) Attributable to Valencia Non-controlling Interest	(3,494)	(3,729)
Preferred Stock Dividend Requirements of Subsidiary	(132)	(132)
Comprehensive Income (Loss) Attributable to PNMR	14,420	(19,310)
PNM
Net Earnings (Loss)	22,162	(12,196)
Unrealized Gains on Available-for-Sale Debt Securities:
Unrealized holding gains arising during the period, net of income tax (expense)	(2,481)	(3,195)
Reclassification adjustment for (gains) included in net earnings, net of income tax expense	(2,699)	(884)
Pension Liability Adjustment:
Reclassification adjustment for amortization of experience (gains) losses recognized as net periodic benefit cost, net of income tax expense (benefit)	1,557	1,548
Fair Value Adjustment for Cash Flow Hedges:
Total Other Comprehensive Income (Loss)	(3,623)	(2,531)
Comprehensive Income (Loss)	18,539	(14,727)
Comprehensive (Income) Attributable to Valencia Non-controlling Interest	(3,494)	(3,729)
Comprehensive Income (Loss) Attributable to PNMR	$ 15,045	$ (18,456)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Unrealized holding gains (losses) arising during the period, income tax (expense) benefit	$ 845	$ 1,088
Reclassification adjustment for (gains) losses included in net earnings, income tax expense (benefit)	919	301
Pension liability adjustment, income tax expense (benefit)	(530)	(527)
Change in fair market value, net of income tax (expense) benefit of $311 and $(472)	(317)	507
Reclassification adjustment for (gains) losses included in net earnings, net of income tax expense (benefit) of $(68) and $13	158	10
PNM
Unrealized holding gains (losses) arising during the period, income tax (expense) benefit	845	1,088
Reclassification adjustment for (gains) losses included in net earnings, income tax expense (benefit)	919	301
Pension liability adjustment, income tax expense (benefit)	$ (530)	$ (527)

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash Flows From Operating Activities:
Net earnings (loss)	$ 21,205	$ (11,399)
Adjustments to reconcile net earnings (loss) to net cash flows from operating activities:
Depreciation and amortization	78,857	77,535
Deferred income tax expense (benefit)	1,447	(1,826)
(Gains) losses on investment securities	(967)	32,849
Stock based compensation expense	4,219	3,801
Allowance for equity funds used during construction	(2,621)	(1,195)
Other, net	3,234	776
Changes in certain assets and liabilities:
Accounts receivable and unbilled revenues	17,205	14,027
Materials, supplies, and fuel stock	4,305	3,806
Other current assets	(18,978)	105
Other assets	6,561	7,429
Accounts payable	(9,647)	(1,224)
Accrued interest and taxes	76	(10,830)
Other current liabilities	(4,369)	(3,570)
Other liabilities	(14,050)	(16,485)
Net cash flows from operating activities	86,477	93,799
Cash Flows From Investing Activities:
Additions to utility plant and non-utility plant	(172,235)	(140,208)
Proceeds from sales of investment securities	123,596	149,355
Purchases of investment securities	(126,485)	(152,108)
Investments in NMRD	0	(10,000)
Distributions from NMRD	572	0
Other, net	97	122
Net cash flows used in investing activities	(174,455)	(152,839)
Cash Flows From Financing Activities:
Revolving credit facilities borrowings (repayments), net	165,500	115,500
Long-term borrowings	220,000	0
Repayment of long-term debt	(300,000)	0
Proceeds from stock option exercise	0	24
Awards of common stock	(9,027)	(11,498)
Dividends paid	(28,243)	(24,625)
Valencia’s transactions with its owner	(5,243)	(6,434)
Transmission interconnection and security deposit arrangements	5,460	370
Refunds paid under transmission interconnection arrangements	(584)	(1,744)
Debt issuance costs and other, net	(292)	(137)
Net cash flows from financing activities	47,571	71,456
Change in Cash, Restricted Cash, and Equivalents	(40,407)	12,416
Cash, Restricted Cash, and Equivalents at Beginning of Period	47,928	3,833
Cash, Restricted Cash, and Equivalents at End of Period	7,521	16,249
Supplemental Cash Flow Disclosures:
Interest paid, net of amounts capitalized	23,317	26,658
Income taxes paid (refunded), net	0	(131)
Supplemental schedule of noncash investing activities:
(Increase) decrease in accrued plant additions	49,092	6,699
PNM
Cash Flows From Operating Activities:
Net earnings (loss)	22,162	(12,196)
Net earnings	18,668	(15,925)
Adjustments to reconcile net earnings (loss) to net cash flows from operating activities:
Depreciation and amortization	50,108	49,422
Deferred income tax expense (benefit)	2,910	(2,141)
(Gains) losses on investment securities	(967)	32,849
Allowance for equity funds used during construction	(2,135)	(1,044)
Other, net	911	811
Changes in certain assets and liabilities:
Accounts receivable and unbilled revenues	17,491	11,927
Materials, supplies, and fuel stock	4,341	4,340
Other current assets	(21,763)	(393)
Other assets	5,780	4,612
Accounts payable	(934)	(260)
Accrued interest and taxes	14,729	5,917
Other current liabilities	(1,911)	746
Other liabilities	(13,196)	(12,588)
Net cash flows from operating activities	77,526	82,002
Cash Flows From Investing Activities:
Additions to utility plant and non-utility plant	(88,198)	(70,586)
Proceeds from sales of investment securities	123,596	149,355
Purchases of investment securities	(126,485)	(152,108)
Other, net	97	122
Net cash flows used in investing activities	(90,990)	(73,217)
Cash Flows From Financing Activities:
Revolving credit facilities borrowings (repayments), net	(10,000)	2,000
Dividends paid	(132)	(132)
Valencia’s transactions with its owner	(5,243)	(6,434)
Transmission interconnection and security deposit arrangements	3,810	370
Refunds paid under transmission interconnection arrangements	(584)	(1,744)
Debt issuance costs and other, net	87	(81)
Net cash flows from financing activities	(12,062)	(6,021)
Change in Cash, Restricted Cash, and Equivalents	(25,526)	2,764
Cash, Restricted Cash, and Equivalents at Beginning of Period	31,446	1,001
Cash, Restricted Cash, and Equivalents at End of Period	5,920	3,765
Supplemental Cash Flow Disclosures:
Interest paid, net of amounts capitalized	7,568	9,397
Income taxes paid (refunded), net	0	0
Supplemental schedule of noncash investing activities:
(Increase) decrease in accrued plant additions	30,828	(2,366)
Texas-New Mexico Power Company
Cash Flows From Operating Activities:
Net earnings	8,735	7,092
Adjustments to reconcile net earnings (loss) to net cash flows from operating activities:
Depreciation and amortization	22,428	22,117
Deferred income tax expense (benefit)	(1,471)	(2,090)
Other, net	(477)	(141)
Changes in certain assets and liabilities:
Accounts receivable and unbilled revenues	(286)	2,099
Materials, supplies, and fuel stock	(36)	(534)
Other current assets	1,231	939
Other assets	1,322	2,310
Accounts payable	(3,182)	(1,828)
Accrued interest and taxes	(9,911)	(11,376)
Other current liabilities	(373)	(2,681)
Other liabilities	(1,310)	(700)
Net cash flows from operating activities	16,670	15,207
Cash Flows From Investing Activities:
Additions to utility plant and non-utility plant	(76,149)	(60,419)
Net cash flows used in investing activities	(76,149)	(60,419)
Cash Flows From Financing Activities:
Revolving credit facilities borrowings (repayments), net	43,100	55,000
Transmission interconnection and security deposit arrangements	1,650	0
Debt issuance costs and other, net	(71)	(53)
Net cash flows from financing activities	44,679	54,947
Change in Cash, Restricted Cash, and Equivalents	(14,800)	9,735
Cash, Restricted Cash, and Equivalents at Beginning of Period	14,800	1,000
Cash, Restricted Cash, and Equivalents at End of Period	0	10,735
Supplemental Cash Flow Disclosures:
Interest paid, net of amounts capitalized	9,229	8,452
Income taxes paid (refunded), net	0	(131)
Supplemental schedule of noncash investing activities:
(Increase) decrease in accrued plant additions	$ 13,465	$ 2,839

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current Assets:
Cash and cash equivalents	$ 7,521	$ 47,928
Accounts receivable, net of allowance for credit losses	102,462	113,410
Unbilled revenues	42,953	55,504
Other receivables	17,979	23,797
Materials, supplies, and fuel stock	62,113	66,417
Regulatory assets	29,133	202
Income taxes receivable	5,553	5,672
Other current assets	60,764	64,549
Total current assets	328,478	377,479
Other Property and Investments:
Investment securities	437,028	440,115
Equity investment in NMRD	87,769	90,655
Other investments	186	284
Non-utility property, net	23,872	24,075
Total other property and investments	548,855	555,129
Utility Plant:
Plant in service, held for future use, and to be abandoned	8,532,455	8,480,799
Less accumulated depreciation and amortization	2,883,146	2,835,170
Net plant in service and plant held for future use	5,649,309	5,645,629
Construction work in progress	282,704	218,719
Nuclear fuel, net of accumulated amortization	98,502	100,801
Net utility plant	6,030,515	5,965,149
Deferred Charges and Other Assets:
Regulatory assets	555,150	557,790
Goodwill	278,297	278,297
Operating lease right-of-use assets, net of accumulated amortization	99,017	105,133
Other deferred charges	102,997	100,877
Total deferred charges and other assets	1,035,461	1,042,097
Assets	7,943,309	7,939,854
Current Liabilities:
Short-term debt	197,500	32,000
Current installments of long-term debt	1,010,559	575,518
Accounts payable	110,577	169,317
Customer deposits	4,877	6,606
Accrued interest and taxes	68,164	68,206
Regulatory liabilities	6,890	7,471
Operating lease liabilities	28,160	27,460
Dividends declared	28,243	28,243
Other current liabilities	56,150	62,841
Total current liabilities	1,511,120	977,662
Long-term Debt, net of Unamortized Premiums, Discounts, and Debt Issuance Costs	2,205,133	2,719,632
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	702,008	694,512
Regulatory liabilities	854,748	850,228
Asset retirement obligations	185,700	183,421
Accrued pension liability and postretirement benefit cost	54,274	58,101
Operating lease liabilities	71,492	81,065
Other deferred credits	259,079	255,230
Total deferred credits and other liabilities	2,127,301	2,122,557
Total liabilities	5,843,554	5,819,851
Commitments and Contingencies (Note 11)
Cumulative Preferred Stock of Subsidiary without mandatory redemption requirements ($100 stated value; 10,000,000 shares authorized; issued and outstanding 115,293 shares)	11,529	11,529
Company common stockholders’ equity:
Common stock	1,425,133	1,429,941
Accumulated other comprehensive income (loss), net of income taxes	(82,342)	(79,183)
Retained earnings	688,175	698,707
Total stockholders' equity	2,030,966	2,049,465
Non-controlling interest in Valencia	57,260	59,009
Total equity	2,088,226	2,108,474
Total liabilities and stockholders' equity	7,943,309	7,939,854
PNM
Current Assets:
Cash and cash equivalents	5,920	31,446
Accounts receivable, net of allowance for credit losses	75,607	88,239
Unbilled revenues	33,927	43,724
Other receivables	16,160	21,814
Affiliate receivables	8,983	8,819
Materials, supplies, and fuel stock	56,132	60,472
Regulatory assets	29,133	0
Income taxes receivable	15,782	15,706
Other current assets	50,441	51,908
Total current assets	292,085	322,128
Other Property and Investments:
Investment securities	437,028	440,115
Other investments	22	120
Non-utility property, net	9,661	9,505
Total other property and investments	446,711	449,740
Utility Plant:
Plant in service, held for future use, and to be abandoned	6,057,687	6,022,753
Less accumulated depreciation and amortization	2,189,978	2,158,915
Net plant in service and plant held for future use	3,867,709	3,863,838
Construction work in progress	165,809	148,962
Nuclear fuel, net of accumulated amortization	98,502	100,801
Net utility plant	4,132,020	4,113,601
Deferred Charges and Other Assets:
Regulatory assets	456,374	457,953
Goodwill	51,632	51,632
Operating lease right-of-use assets, net of accumulated amortization	91,652	97,461
Other deferred charges	90,672	88,518
Total deferred charges and other assets	690,330	695,564
Assets	5,561,146	5,581,033
Current Liabilities:
Short-term debt	0	10,000
Current installments of long-term debt	345,701	345,570
Accounts payable	89,288	121,050
Affiliate payables	8,475	14,058
Customer deposits	4,877	6,606
Accrued interest and taxes	47,434	32,630
Regulatory liabilities	4,734	5,419
Operating lease liabilities	25,868	25,130
Dividends declared	132	132
Other current liabilities	36,410	33,737
Total current liabilities	562,919	594,332
Long-term Debt, net of Unamortized Premiums, Discounts, and Debt Issuance Costs	1,351,494	1,351,050
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	586,266	579,150
Regulatory liabilities	663,429	664,873
Asset retirement obligations	184,982	182,718
Accrued pension liability and postretirement benefit cost	52,826	56,273
Operating lease liabilities	66,657	75,941
Other deferred credits	204,128	201,415
Total deferred credits and other liabilities	1,758,288	1,760,370
Total liabilities	3,672,701	3,705,752
Commitments and Contingencies (Note 11)
Cumulative Preferred Stock of Subsidiary without mandatory redemption requirements ($100 stated value; 10,000,000 shares authorized; issued and outstanding 115,293 shares)	11,529	11,529
Company common stockholders’ equity:
Common stock	1,494,918	1,494,918
Accumulated other comprehensive income (loss), net of income taxes	(82,134)	(78,511)
Retained earnings	406,872	388,336
Total stockholders' equity	1,819,656	1,804,743
Non-controlling interest in Valencia	57,260	59,009
Total equity	1,876,916	1,863,752
Total liabilities and stockholders' equity	5,561,146	5,581,033
Texas-New Mexico Power Company
Current Assets:
Cash and cash equivalents	0	14,800
Accounts receivable, net of allowance for credit losses	26,855	25,171
Unbilled revenues	9,026	11,780
Other receivables	3,610	3,703
Affiliate receivables	64	0
Materials, supplies, and fuel stock	5,981	5,945
Regulatory assets	0	202
Other current assets	897	1,738
Total current assets	46,433	63,339
Other Property and Investments:
Other investments	164	164
Non-utility property, net	12,942	13,298
Total other property and investments	13,106	13,462
Utility Plant:
Plant in service, held for future use, and to be abandoned	2,208,601	2,193,270
Less accumulated depreciation and amortization	548,896	537,707
Net plant in service and plant held for future use	1,659,705	1,655,563
Construction work in progress	107,000	61,359
Net utility plant	1,766,705	1,716,922
Deferred Charges and Other Assets:
Regulatory assets	98,776	99,837
Goodwill	226,665	226,665
Operating lease right-of-use assets, net of accumulated amortization	6,937	7,206
Other deferred charges	4,628	5,149
Total deferred charges and other assets	337,006	338,857
Assets	2,163,250	2,132,580
Current Liabilities:
Short-term debt	43,100	0
Accounts payable	16,973	33,620
Affiliate payables	3,460	5,883
Accrued interest and taxes	31,626	41,538
Regulatory liabilities	2,156	2,052
Operating lease liabilities	2,185	2,193
Other current liabilities	6,051	4,486
Total current liabilities	105,551	89,772
Long-term Debt, net of Unamortized Premiums, Discounts, and Debt Issuance Costs	853,639	853,673
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	145,582	145,369
Regulatory liabilities	191,319	185,355
Asset retirement obligations	718	703
Accrued pension liability and postretirement benefit cost	1,448	1,828
Operating lease liabilities	4,515	4,779
Other deferred credits	26,065	25,423
Total deferred credits and other liabilities	369,647	363,457
Total liabilities	1,328,837	1,306,902
Commitments and Contingencies (Note 11)
Company common stockholders’ equity:
Common stock	64	64
Paid-in-capital	685,166	685,166
Retained earnings	149,183	140,448
Total stockholders' equity	834,413	825,678
Total liabilities and stockholders' equity	$ 2,163,250	$ 2,132,580

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Allowance for uncollectible accounts	$ 11,274,000	$ 8,333,000
Accumulated depreciation, nuclear fuel	$ 47,253,000	$ 41,367,000
Cumulative preferred stock of subsidiary, stated value (in dollars per share)	$ 100	$ 100
Cumulative preferred stock of subsidiary, shares authorized (in shares)	10,000,000	10,000,000
Cumulative preferred stock of subsidiary, shares issued (in shares)	115,293	115,293
Cumulative preferred stock of subsidiary, shares outstanding (in shares)	115,293	115,293
Common stock, no par value (in dollars per share)	$ 0	$ 0
Common stock, shares authorized (in shares)	120,000,000	120,000,000
Common stock, shares issued (in shares)	85,834,874	85,834,874
Common stock, shares outstanding (in shares)	85,834,874	85,834,874
PNM
Allowance for uncollectible accounts	$ 9,918,000	$ 8,333,000
Accumulated depreciation, nuclear fuel	$ 47,253,000	$ 41,367,000
Cumulative preferred stock, stated value (in dollars per share)	$ 100	$ 100
Cumulative preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Cumulative preferred stock, shares issued (in shares)	115,293	115,293
Cumulative preferred stock, shares outstanding (in shares)	115,293	115,293
Common stock, no par value (in dollars per share)	$ 0	$ 0
Common stock, shares authorized (in shares)	40,000,000	40,000,000
Common stock, shares issued (in shares)	39,117,799	39,117,799
Common stock, shares outstanding (in shares)	39,117,799	39,117,799
Texas-New Mexico Power Company
Allowance for uncollectible accounts	$ 1,356,000	$ 0
Common stock, par value (in dollars per share)	$ 10	$ 10
Common stock, shares authorized (in shares)	12,000,000	12,000,000
Common stock, shares issued (in shares)	6,358	6,358
Common stock, shares outstanding (in shares)	6,358	6,358

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Total PNMR Common Stockholders’ Equity	Common Stock	AOCI	Retained Earnings	Non- controlling Interest in Valencia	PNM	PNMTotal PNMR Common Stockholders’ Equity	PNMCommon Stock	PNMAOCI	PNMRetained Earnings	PNMNon- controlling Interest in Valencia	Texas-New Mexico Power Company	Texas-New Mexico Power CompanyCommon Stock	Texas-New Mexico Power CompanyPaid-in Capital	Texas-New Mexico Power CompanyRetained Earnings
Beginning balance at Dec. 31, 2019	$ 1,741,750	$ 1,678,698	$ 1,150,552	$ (99,377)	$ 627,523	$ 63,052	$ 1,512,431	$ 1,449,379	$ 1,264,918	$ (99,055)	$ 283,516	$ 63,052
Beginning balance TNMP at Dec. 31, 2019													$ 754,627	$ 64	$ 614,166	$ 140,397
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings before subsidiary preferred stock dividends	(11,399)	(15,128)			(15,128)	3,729	(12,196)	(15,925)			(15,925)	3,729
Net earnings							(15,925)						7,092			7,092
Total other comprehensive income (loss)	(4,050)	(4,050)		(4,050)			(2,531)	(2,531)		(2,531)
Subsidiary preferred stock dividends	(132)	(132)			(132)
Dividends declared on preferred stock							(132)	(132)			(132)
Dividends declared on common stock	(24,493)	(24,493)			(24,493)		(40,654)	(40,654)			(40,654)		(11,347)			(11,347)
Proceeds from stock option exercise	24	24	24
Awards of common stock	(11,498)	(11,498)	(11,498)
Stock based compensation expense	3,801	3,801	3,801
Valencia’s transactions with its owner	(6,434)					(6,434)	(6,434)					(6,434)
Ending balance at Mar. 31, 2020	1,687,569	1,627,222	1,142,879	(103,427)	587,770	60,347	1,450,484	1,390,137	1,264,918	(101,586)	226,805	60,347
Ending balance TNMP at Mar. 31, 2020													750,372	64	614,166	136,142
Beginning balance at Dec. 31, 2020	2,108,474	2,049,465	1,429,941	(79,183)	698,707	59,009	1,863,752	1,804,743	1,494,918	(78,511)	388,336	59,009
Beginning balance TNMP at Dec. 31, 2020	2,049,465						1,804,743						825,678	64	685,166	140,448
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings before subsidiary preferred stock dividends	21,205	17,711			17,711	3,494	22,162	18,668			18,668	3,494
Net earnings							18,668						8,735			8,735
Total other comprehensive income (loss)	(3,159)	(3,159)		(3,159)			(3,623)	(3,623)		(3,623)
Subsidiary preferred stock dividends	(132)	(132)			(132)
Dividends declared on preferred stock							(132)	(132)			(132)
Dividends declared on common stock	(28,111)	(28,111)			(28,111)
Awards of common stock	(9,027)	(9,027)	(9,027)
Stock based compensation expense	4,219	4,219	4,219
Valencia’s transactions with its owner	(5,243)					(5,243)	(5,243)					(5,243)
Ending balance at Mar. 31, 2021	2,088,226	$ 2,030,966	$ 1,425,133	$ (82,342)	$ 688,175	$ 57,260	1,876,916	$ 1,819,656	$ 1,494,918	$ (82,134)	$ 406,872	$ 57,260
Ending balance TNMP at Mar. 31, 2021	$ 2,030,966						$ 1,819,656						$ 834,413	$ 64	$ 685,166	$ 149,183

Significant Accounting Policies

Significant Accounting Policies and Responsibility for Financial Statements	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Significant Accounting Policies and Responsibility for Financial Statements	Significant Accounting Policies and Responsibility for Financial Statements Financial Statement Preparation In the opinion of management, the accompanying unaudited interim Condensed Consolidated Financial Statements reflect all normal and recurring accruals and adjustments that are necessary to present fairly the consolidated financial position at March 31, 2021 and December 31, 2020, and the consolidated results of operations, comprehensive income, and cash flows for the three months ended March 31, 2021 and 2020. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could ultimately differ from those estimated. Weather causes the Company’s results of operations to be seasonal in nature and the results of operations presented in the accompanying Condensed Consolidated Financial Statements are not necessarily representative of operations for an entire year. The Notes to Condensed Consolidated Financial Statements include disclosures for PNMR, PNM, and TNMP. This report uses the term “Company” when discussing matters of common applicability to PNMR, PNM, and TNMP. Discussions regarding only PNMR, PNM, or TNMP are so indicated. Certain amounts in the 2020 Condensed Consolidated Financial Statements and Notes thereto have been reclassified to conform to the 2021 financial statement presentation. These Condensed Consolidated Financial Statements are unaudited. Certain information and note disclosures normally included in the annual audited Consolidated Financial Statements have been condensed or omitted, as permitted under the applicable rules and regulations. Readers of these financial statements should refer to PNMR’s, PNM’s, and TNMP’s audited Consolidated Financial Statements and Notes thereto that are included in their respective 2020 Annual Reports on Form 10-K. GAAP defines subsequent events as events or transactions that occur after the balance sheet date but before financial statements are issued or are available to be issued. Based on their nature, magnitude, and timing, certain subsequent events may be required to be reflected at the balance sheet date and/or required to be disclosed in the financial statements. The Company has evaluated subsequent events accordingly. Principles of Consolidation The Condensed Consolidated Financial Statements of each of PNMR, PNM, and TNMP include their accounts and those of subsidiaries in which that entity owns a majority voting interest. PNM also consolidates Valencia. See Note 6. PNM owns undivided interests in several jointly-owned power plants and records its pro-rata share of the assets, liabilities, and expenses for those plants. The agreements for the jointly-owned plants provide that if an owner were to default on its payment obligations, the non-defaulting owners would be responsible for their proportionate share of the obligations of the defaulting owner. In exchange, the non-defaulting owners would be entitled to their proportionate share of the generating capacity of the defaulting owner. There have been no such payment defaults under any of the agreements for the jointly-owned plants. PNMR Services Company expenses, which represent costs that are primarily driven by corporate level activities, are charged to the business segments. These services are billed at cost and are reflected as general and administrative expenses in the business segments. Other significant intercompany transactions between PNMR, PNM, and TNMP include interest and income tax sharing payments, as well as equity transactions, and interconnection billings. See Note 15. All intercompany transactions and balances have been eliminated. Dividends on Common Stock Dividends on PNMR’s common stock are declared by the Board. The timing of the declaration of dividends is dependent on the timing of meetings and other actions of the Board. The Board declared dividends on common stock of $0.3275 per share in March 2021 and $0.3075 per share in February 2020, which are reflected as "Dividends Declared per Common Share" on the PNMR Condensed Consolidated Statements of Earnings. PNM declared cash dividends on its common stock to PNMR of $40.7 million in the three months ended March 31, 2020 that were subsequently paid on April 6, 2020. TNMP declared cash dividends on its common stock to PNMR of $11.3 million in the three months ended March 31, 2020 that were subsequently paid on April 1, 2020. Neither PNM nor TNMP declared or paid any cash dividends in the three months ended March 31, 2021.

Segment Information

Segment Information	3 Months Ended
	Mar. 31, 2021
Segment Reporting [Abstract]
Segment Information	Segment Information The following segment presentation is based on the methodology that management uses for making operating decisions and assessing performance of its various business activities. A reconciliation of the segment presentation to the GAAP financial statements is provided. PNM PNM includes the retail electric utility operations of PNM that are subject to traditional rate regulation by the NMPRC. PNM provides integrated electricity services that include the generation, transmission, and distribution of electricity for retail electric customers in New Mexico. PNM also includes the generation and sale of electricity into the wholesale market, as well as providing transmission services to third parties. The sale of electricity includes the asset optimization of PNM’s jurisdictional capacity, as well as the capacity excluded from retail rates. FERC has jurisdiction over wholesale power and transmission rates. TNMP TNMP is an electric utility providing services in Texas under the TECA. TNMP’s operations are subject to traditional rate regulation by the PUCT. TNMP provides transmission and distribution services at regulated rates to various REPs that, in turn, provide retail electric service to consumers within TNMP’s service area. TNMP also provides transmission services at regulated rates to other utilities that interconnect with TNMP’s facilities. Corporate and Other The Corporate and Other segment includes PNMR holding company activities, primarily related to corporate level debt and PNMR Services Company. The activities of PNMR Development, NM Capital, and the equity method investment in NMRD are also included in Corporate and Other. Eliminations of intercompany transactions are reflected in the Corporate and Other segment. The following tables present summarized financial information for PNMR by segment. PNM and TNMP each operate in only one segment. Therefore, tabular segment information is not presented for PNM and TNMP. PNMR SEGMENT INFORMATION PNM TNMP Corporate PNMR Consolidated (In thousands) Three Months Ended March 31, 2021 Electric operating revenues $ 271,213 $ 93,494 $ — $ 364,707 Cost of energy 88,886 26,510 — 115,396 Utility margin 182,327 66,984 — 249,311 Other operating expenses 107,328 27,769 1,174 136,271 Depreciation and amortization 41,949 22,190 5,735 69,874 Operating income (loss) 33,050 17,025 (6,909) 43,166 Interest income 3,595 — (36) 3,559 Other income 1,244 1,062 (376) 1,930 Interest charges (12,893) (8,475) (4,516) (25,884) Segment earnings (loss) before income taxes 24,996 9,612 (11,837) 22,771 Income taxes (benefit) 2,834 877 (2,145) 1,566 Segment earnings (loss) 22,162 8,735 (9,692) 21,205 Valencia non-controlling interest (3,494) — — (3,494) Subsidiary preferred stock dividends (132) — — (132) Segment earnings (loss) attributable to PNMR $ 18,536 $ 8,735 $ (9,692) $ 17,579 At March 31, 2021: Total Assets $ 5,561,146 $ 2,163,250 $ 218,913 $ 7,943,309 Goodwill $ 51,632 $ 226,665 $ — $ 278,297 PNM TNMP Corporate PNMR Consolidated (In thousands) Three Months Ended March 31, 2020 Electric operating revenues $ 248,133 $ 85,489 $ — $ 333,622 Cost of energy 74,524 24,186 — 98,710 Utility margin 173,609 61,303 — 234,912 Other operating expenses 98,555 25,122 (5,476) 118,201 Depreciation and amortization 41,449 21,836 5,688 68,973 Operating income (loss) 33,605 14,345 (212) 47,738 Interest income 3,496 — (73) 3,423 Other income (deductions) (34,027) 561 (540) (34,006) Interest charges (17,629) (7,172) (5,633) (30,434) Segment earnings (loss) before income taxes (14,555) 7,734 (6,458) (13,279) Income taxes (benefit) (2,359) 642 (163) (1,880) Segment earnings (loss) (12,196) 7,092 (6,295) (11,399) Valencia non-controlling interest (3,729) — — (3,729) Subsidiary preferred stock dividends (132) — — (132) Segment earnings (loss) attributable to PNMR $ (16,057) $ 7,092 $ (6,295) $ (15,260) At March 31, 2020: Total Assets $ 5,260,528 $ 1,913,270 $ 201,321 $ 7,375,119 Goodwill $ 51,632 $ 226,665 $ — $ 278,297 The Company defines utility margin as electric operating revenues less cost of energy. Cost of energy consists primarily of fuel and purchase power costs for PNM and costs charged by third-party transmission providers for TNMP. The Company believes that utility margin provides a more meaningful basis for evaluating operations than electric operating revenues since substantially all such costs are offset in revenues as fuel and purchase power costs are passed through to customers under PNM’s FPPAC and third-party transmission costs are passed on to customers through TNMP’s transmission cost recovery factor. Utility margin is not a financial measure required to be presented and is considered a non-GAAP measure.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income (Loss) Information regarding accumulated other comprehensive income (loss) for the three months ended March 31, 2021 and 2020 is as follows: Accumulated Other Comprehensive Income (Loss) PNM Corporate and Other PNMR Consolidated Unrealized Pension Fair Value Total Total (In thousands) Balance at December 31, 2020 $ 20,403 $ (98,914) $ (78,511) $ (672) $ (79,183) Amounts reclassified from AOCI (pre-tax) (3,618) 2,087 (1,531) (624) (2,155) Income tax impact of amounts reclassified 919 (530) 389 158 547 Other OCI changes (pre-tax) (3,326) — (3,326) 1,247 (2,079) Income tax impact of other OCI changes 845 — 845 (317) 528 Net after-tax change (5,180) 1,557 (3,623) 464 (3,159) Balance at March 31, 2021 $ 15,223 $ (97,357) $ (82,134) $ (208) $ (82,342) Balance at December 31, 2019 $ 10,638 $ (109,693) $ (99,055) $ (322) $ (99,377) Amounts reclassified from AOCI (pre-tax) (1,185) 2,075 890 (38) 852 Income tax impact of amounts reclassified 301 (527) (226) 10 (216) Other OCI changes (pre-tax) (4,283) — (4,283) (1,998) (6,281) Income tax impact of other OCI changes 1,088 — 1,088 507 1,595 Net after-tax change (4,079) 1,548 (2,531) (1,519) (4,050) Balance at March 31, 2020 $ 6,559 $ (108,145) $ (101,586) $ (1,841) $ (103,427) The Condensed Consolidated Statements of Earnings include pre-tax amounts reclassified from AOCI related to Unrealized Gains on Available-for-Sale Debt Securities in gains (losses) on investment securities, related to Pension Liability Adjustment in other (deductions), and related to Fair Value Adjustment for Cash Flow Hedges in interest charges. The income tax impacts of all amounts reclassified from AOCI are included in income taxes in the Condensed Consolidated Statements of Earnings.

Earnings Per Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share Dual presentation of basic and diluted earnings per share is presented in the Condensed Consolidated Statements of Earnings of PNMR. PNMR’s potentially dilutive shares consist of restricted stock and PNMR common stock issuable in 2020 under the PNMR 2020 Forward Equity Sale Agreements, which are calculated under the treasury stock method. See Note 7 of the Notes to Consolidated Financial Statements in the 2020 Annual Reports on Form 10-K. Information regarding the computation of earnings per share is as follows: Three Months Ended March 31, 2021 2020 (In thousands, except per share amounts) Net Earnings (Loss) Attributable to PNMR $ 17,579 $ (15,260) Average Number of Common Shares: Outstanding during period 85,835 79,654 Vested awards of restricted stock 196 217 Average Shares – Basic 86,031 79,871 Dilutive Effect of Common Stock Equivalents: Restricted stock 24 — Average Shares – Diluted 86,055 79,871 Net Earnings (Loss) Per Share of Common Stock: Basic $ 0.20 $ (0.19) Diluted $ 0.20 $ (0.19) (1) No potentially dilutive restricted stock or PNMR common stock under the PNMR 2020 Forward Equity Sale Agreements have been included in the computation of Average Shares – Diluted for the three months ended March 31, 2020 since the effect would be anti-dilutive.

Electric Operating Revenues

Electric Operating Revenues	3 Months Ended
	Mar. 31, 2021
Revenue from Contract with Customer [Abstract]
Electric Operating Revenues	Electric Operating Revenues PNMR is an investor-owned holding company with two regulated utilities providing electricity and electric services in New Mexico and Texas. PNMR’s electric utilities are PNM and TNMP. Additional information concerning electric operating revenue is contained in Note 4 of the Notes to Consolidated Financial Statements in the 2020 Annual Reports on Form 10-K. Accounts Receivable and Allowance for Credit Losses Accounts receivable consists primarily of trade receivables from customers. In the normal course of business, credit is extended to customers on a short-term basis. The Company estimates the allowance for credit losses on trade receivables based on historical experience and estimated default rates. Accounts receivable balances are reviewed monthly, adjustments to the allowance for credit losses are made as necessary, and amounts that are deemed uncollectible are written off. As a result of the economic conditions resulting from the COVID-19 pandemic, PNM updated its allowance for accounts receivable balances and recorded incremental credit losses of $1.6 million and $0.3 million in the three months ended March 31, 2021 and 2020. The NMPRC issued an order authorizing all public utilities to create a regulatory asset to defer incremental costs related to COVID-19, including increases in uncollectible accounts. See discussion regarding regulatory treatment in Note 12. In February 2021, Texas experienced a severe winter storm delivering the coldest temperatures in 100 years for many parts of the state. As a result, the ERCOT market was not able to deliver sufficient generation load to the grid resulting in significant, statewide outages as ERCOT directed transmission operators to curtail thousands of firm load megawatts. TNMP complied with ERCOT directives to curtail delivery of electricity in its service territory and did not experience significant outages on its system outside of the ERCOT directed curtailments. During the weather event, generators experienced an extreme spike in market driven fuel prices and in turn charged REPs excessive market driven power prices which eventually get passed to end users on their electricity bill. Given the uncertainty of the collectability of end users bills by REP’s, ERCOT also increased the collateral required by REPs in order to do business within ERCOT's Balancing Authority. In response to the uncertainty, TNMP has performed an analysis of its accounts receivable balances and has recorded an allowance for credit losses of $1.4 million as of March 31, 2021. TNMP has regulatory authorization to defer bad debt expense (credit losses) from defaulting REPs to a regulatory asset and seek recovery in a general rate case. Disaggregation of Revenues A disaggregation of revenues from contracts with customers by the type of customer is presented in the table below. The table also reflects alternative revenue program revenues ("ARP") and other revenues. PNM TNMP PNMR Consolidated Three Months Ended March 31, 2021 (In thousands) Electric Operating Revenues: Contracts with customers: Retail electric revenue Residential $ 114,669 $ 35,094 $ 149,763 Commercial 81,934 29,429 111,363 Industrial 18,900 7,293 26,193 Public authority 4,587 1,482 6,069 Economy energy service 10,581 — 10,581 Transmission 17,503 21,121 38,624 Miscellaneous 3,032 960 3,992 Total revenues from contracts with customers 251,206 95,379 346,585 Alternative revenue programs 976 (1,885) (909) Other electric operating revenues 19,031 — 19,031 Total Electric Operating Revenues $ 271,213 $ 93,494 $ 364,707 Three Months Ended March 31, 2020 Electric Operating Revenues: Contracts with customers: Retail electric revenue Residential $ 102,809 $ 31,898 $ 134,707 Commercial 86,349 28,685 115,034 Industrial 19,466 6,533 25,999 Public authority 4,347 1,423 5,770 Economy energy service 5,253 — 5,253 Transmission 14,167 18,012 32,179 Miscellaneous 3,368 673 4,041 Total revenues from contracts with customers 235,759 87,224 322,983 Alternative revenue programs 2,161 (1,735) 426 Other electric operating revenues 10,213 — 10,213 Total Electric Operating Revenues $ 248,133 $ 85,489 $ 333,622 Contract Balances Performance obligations related to contracts with customers are typically satisfied when the energy is delivered and the customer or end-user utilizes the energy. Accounts receivable from customers represent amounts billed, including amounts under ARPs. For PNM, accounts receivable reflected on the Condensed Consolidated Balance Sheets, net of allowance for credit losses, includes $73.2 million at March 31, 2021 and $86.2 million at December 31, 2020 resulting from contracts with customers. All of TNMP’s accounts receivable results from contracts with customers.

Variable Interest Entities

Variable Interest Entities	3 Months Ended
	Mar. 31, 2021
Variable Interest Entities [Abstract]
Variable Interest Entities	Variable Interest Entities How an enterprise evaluates and accounts for its involvement with variable interest entities, focuses primarily on whether the enterprise has the power to direct the activities that most significantly impact the economic performance of a variable interest entity (“VIE”). This evaluation requires continual reassessment of the primary beneficiary of a VIE. Additional information concerning PNM’s VIEs is contained in Note 10 of the Notes to Consolidated Financial Statements in the 2020 Annual Reports on Form 10-K. Valencia PNM has a PPA to purchase all of the electric capacity and energy from Valencia, a 155 MW natural gas-fired power plant near Belen, New Mexico, through May 2028. A third party built, owns, and operates the facility while PNM is the sole purchaser of the electricity generated. PNM is obligated to pay fixed operation and maintenance and capacity charges in addition to variable operation and maintenance charges under this PPA. For the three months ended March 31, 2021 and 2020, PNM paid $4.9 million and $5.0 million for fixed charges and $0.2 million and $0.4 million for variable charges. PNM does not have any other financial obligations related to Valencia. The assets of Valencia can only be used to satisfy its obligations and creditors of Valencia do not have any recourse against PNM’s assets. During the term of the PPA, PNM has the option, under certain conditions, to purchase and own up to 50% of the plant or the VIE. The PPA specifies that the purchase price would be the greater of 50% of book value reduced by related indebtedness or 50% of fair market value. PNM sources fuel for the plant, controls when the facility operates through its dispatch, and receives the entire output of the plant, which factors directly and significantly impact the economic performance of Valencia. Therefore, PNM has concluded that the third-party entity that owns Valencia is a VIE and that PNM is the primary beneficiary of the entity since PNM has the power to direct the activities that most significantly impact the economic performance of Valencia and will absorb the majority of the variability in the cash flows of the plant. As the primary beneficiary, PNM consolidates Valencia in its financial statements. Accordingly, the assets, liabilities, operating expenses, and cash flows of Valencia are included in the Condensed Consolidated Financial Statements of PNM although PNM has no legal ownership interest or voting control of the VIE. The assets and liabilities of Valencia set forth below are immaterial to PNM and, therefore, not shown separately on the Condensed Consolidated Balance Sheets. The owner’s equity and net income of Valencia are considered attributable to non-controlling interest. Summarized financial information for Valencia is as follows: Results of Operations Three Months Ended March 31, 2021 2020 (In thousands) Operating revenues $ 5,127 $ 5,353 Operating expenses 1,633 1,624 Earnings attributable to non-controlling interest $ 3,494 $ 3,729 Financial Position March 31, December 31, 2021 2020 (In thousands) Current assets $ 3,282 $ 3,911 Net property, plant, and equipment 55,035 55,744 Total assets 58,317 59,655 Current liabilities 1,057 646 Owners’ equity – non-controlling interest $ 57,260 $ 59,009 Westmoreland San Juan Mining, LLC As discussed in the subheading Coal Supply in Note 11, PNM purchases coal for SJGS under the SJGS CSA. On October 9, 2018, Westmoreland filed a Current Report on Form 8-K with the SEC announcing it had filed voluntary petitions for relief under Chapter 11 of the U.S. Bankruptcy Code. On March 15, 2019, Westmoreland emerged from Chapter 11 bankruptcy as a privately held company owned and operated by a group of its former creditors. Under the reorganization, the assets of SJCC were sold to Westmoreland San Juan Mining, LLC (“WSJ LLC”), a subsidiary of Westmoreland Mining Holdings, LLC. As successor entity to SJCC, WSJ LLC assumed all rights and obligations of SJCC including obligations to PNM under the SJGS CSA and to PNMR under letter of credit support agreements. PNMR issued $30.3 million in letters of credit to facilitate the issuance of reclamation bonds required in order for SJCC to mine coal to be supplied to SJGS. As discussed above, WSJ LLC assumed the rights and obligations of SJCC, including obligations to PNMR for the letters of credit. The letters of credit support results in PNMR having a variable interest in WSJ LLC since PNMR is subject to possible loss in the event performance by PNMR is required under the letters of credit support. PNMR considers the possibility of loss under the letters of credit support to be remote since the purpose of posting the bonds is to provide assurance that WSJ LLC performs the required reclamation of the mine site in accordance with applicable regulations and all reclamation costs are reimbursable under the SJGS CSA. Also, much of the mine reclamation activities will not be performed until after the expiration of the SJGS CSA. In addition, each of the SJGS participants has established and actively fund trusts to meet future reclamation obligations.

Fair Value of Derivative and Ot

Fair Value of Derivative and Other Financial Instruments	3 Months Ended
	Mar. 31, 2021
Fair Value of Derivative and Other Financial Instruments [Abstract]
Fair Value of Derivative and Other Financial Instruments	Fair Value of Derivative and Other Financial Instruments Additional information concerning energy related derivative contracts and other financial instruments is contained in Note 9 of the Notes to Consolidated Financial Statements in the 2020 Annual Reports on Form 10-K. Fair value is defined as the price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Fair value is based on current market quotes as available and is supplemented by modeling techniques and assumptions made by the Company to the extent quoted market prices or volatilities are not available. External pricing input availability varies based on commodity location, market liquidity, and term of the agreement. Valuations of derivative assets and liabilities take into account nonperformance risk, including the effect of counterparties’ and the Company’s credit risk. The Company regularly assesses the validity and availability of pricing data for its derivative transactions. Although the Company uses its best judgment in estimating the fair value of these instruments, there are inherent limitations in any estimation technique. Energy Related Derivative Contracts Overview The primary objective for the use of commodity derivative instruments, including energy contracts, options, swaps, and futures, is to manage price risk associated with forecasted purchases of energy and fuel used to generate electricity, as well as managing anticipated generation capacity in excess of forecasted demand from existing customers. PNM’s energy related derivative contracts manage commodity risk. PNM is required to meet the demand and energy needs of its customers. PNM is exposed to market risk for the needs of its customers not covered under the FPPAC. Beginning January 1, 2018, PNM is exposed to market risk for its 65 MW interest in SJGS Unit 4, which is held as merchant plant as ordered by the NMPRC. PNM has entered into agreements to sell power from 36 MW of that capacity to a third party at a fixed price for the period January 1, 2018 through May 31, 2022, subject to certain conditions. Under these agreements, PNM is obligated to deliver 36 MW of power only when SJGS Unit 4 is operating. These agreements are not considered derivatives because there is no notional amount due to the unit-contingent nature of the transactions. PNM and Tri-State have a hazard sharing agreement that expires in May 2022. Under this agreement, each party sells the other party 100 MW of capacity and energy from a designated generation resource on a unit contingent basis, subject to certain performance guarantees. Both the purchases and sales are made at the same market index price. This agreement serves to reduce the magnitude of each party’s single largest generating hazard and assists in enhancing the reliability and efficiency of their respective operations. PNM passes the sales and purchases through to customers under PNM’s FPPAC. PNM’s operations are managed primarily through a net asset-backed strategy, whereby PNM’s aggregate net open forward contract position is covered by its forecasted excess generation capabilities or market purchases. PNM could be exposed to market risk if its generation capabilities were to be disrupted or if its load requirements were to be greater than anticipated. If all or a portion of load requirements were required to be covered as a result of such unexpected situations, commitments would have to be met through market purchases. TNMP does not enter into energy related derivative contracts. Commodity Risk Marketing and procurement of energy often involve market risks associated with managing energy commodities and establishing positions in the energy markets, primarily on a short-term basis. PNM routinely enters into various derivative instruments such as forward contracts, option agreements, and price basis swap agreements to economically hedge price and volume risk on power commitments and fuel requirements and to minimize the effect of market fluctuations. PNM monitors the market risk of its commodity contracts in accordance with approved risk and credit policies. Unusually cold weather in February 2021 resulted in higher than expected natural gas and purchased power costs. PNM mitigated the impacts from the cold weather by securing gas supplies in advance, engaging in market purchases when lower prices were available, and adjusting plant operation of its gas units to minimize reliance on higher-priced gas supplies. PNM estimates the impact of the cold weather conditions in 2021 resulted in approximately $20 million of additional natural gas costs and approximately $8 million in additional purchased power costs. These increases will be passed through to customers under the FPPAC over the remainder of 2021. Accounting for Derivatives Under derivative accounting and related rules for energy contracts, PNM accounts for its various instruments for the purchase and sale of energy, which meet the definition of a derivative, based on PNM’s intent. During the three months ended March 31, 2021 and the year ended December 31, 2020, PNM was not hedging its exposure to the variability in future cash flows from commodity derivatives through designated cash flows hedges. The derivative contracts recorded at fair value that do not qualify or are not designated for cash flow hedge accounting are classified as economic hedges. Economic hedges are defined as derivative instruments, including long-term power agreements, used to economically hedge generation assets, purchased power and fuel costs, and customer load requirements. Changes in the fair value of economic hedges are reflected in results of operations and are classified between operating revenues and cost of energy according to the intent of the hedge. PNM has no trading transactions. Commodity Derivatives PNM’s commodity derivative instruments that are recorded at fair value, all of which are accounted for as economic hedges and considered Level 2 fair value measurements, are presented in the following line items on the Condensed Consolidated Balance Sheets: Economic Hedges March 31, December 31, (In thousands) Other current assets $ 1,097 $ 1,096 Other deferred charges 183 455 1,280 1,551 Other current liabilities (1,097) (1,096) Other deferred credits (183) (455) (1,280) (1,551) Net $ — $ — PNM’s commodity derivative instruments in the above table are subject to master netting agreements whereby assets and liabilities could be offset in the settlement process. PNM does not offset fair value and cash collateral for derivative instruments under master netting arrangements and the above table reflects the gross amounts of fair value assets and liabilities for commodity derivatives. All of the assets and liabilities in the table above at March 31, 2021 and December 31, 2020 result from PNM’s hazard sharing arrangements with Tri-State. The hazard sharing arrangements are net-settled upon delivery. At March 31, 2021 and December 31, 2020, PNM had no amounts recognized for the legal right to reclaim cash collateral. However, at both March 31, 2021 and December 31, 2020, amounts posted as cash collateral under margin arrangements were $0.5 million, which is included in other current assets on the Condensed Consolidated Balance Sheets. At both March 31, 2021 and December 31, 2020, obligations to return cash collateral were $0.9 million, which is included in other deferred credits on the Condensed Consolidated Balance Sheets. PNM has a NMPRC-approved hedging plan to manage fuel and purchased power costs related to customers covered by its FPPAC. There were no amounts hedged under this plan as of March 31, 2021 or December 31, 2020. The effects of mark-to-market commodity derivative instruments on PNM’s revenues and cost of energy during the three months ended March 31, 2021 and 2020 were less than $0.1 million. Commodity derivatives had no impact on OCI for the periods presented. PNM has no open energy or gas commodity volume positions at March 31, 2021 or December 31, 2020. PNM has contingent requirements to provide collateral under commodity contracts having an objectively determinable collateral provision that are in net liability positions and are not fully collateralized with cash. In connection with managing its commodity risks, PNM enters into master agreements with certain counterparties. If PNM is in a net liability position under an agreement, some agreements provide that the counterparties can request collateral if PNM’s credit rating is downgraded; other agreements provide that the counterparty may request collateral to provide it with “adequate assurance” that PNM will perform; and others have no provision for collateral. At March 31, 2021 and December 31, 2020, PNM had no such contracts in a net liability position. Non-Derivative Financial Instruments The carrying amounts reflected on the Condensed Consolidated Balance Sheets approximate fair value for cash, receivables, and payables due to the short period of maturity. Investment securities are carried at fair value. Investment securities consist of PNM assets held in the NDT for its share of decommissioning costs of PVNGS and trusts for PNM’s share of final reclamation costs related to the coal mines serving SJGS and Four Corners. See Note 11. At March 31, 2021 and December 31, 2020, the fair value of investment securities included $376.8 million and $379.2 million for the NDT and $60.2 million and $60.9 million for the mine reclamation trusts. PNM records a realized loss as an impairment for any available-for-sale debt security that has a fair value that is less than its carrying value. At March 31, 2021 and December 31, 2020, PNM had no available-for-sale debt securities for which carrying value exceeds fair value and there are no impairments considered to be “other than temporary” that are included in AOCI and not recognized in earnings. All gains and losses resulting from sales and changes in the fair value of equity securities are recognized immediately in earnings. Gains and losses recognized on the Condensed Consolidated Statements of Earnings related to investment securities in the NDT and reclamation trusts are presented in the following table: Three Months Ended March 31, 2021 2020 (In thousands) Equity securities: Net gains (losses) from equity securities sold $ 2,022 $ (1,315) Net gains (losses) from equity securities still held (3,166) (18,931) Total net gains (losses) on equity securities (1,144) (20,246) Available-for-sale debt securities: Net gains (losses) on debt securities 2,112 (12,603) Net gains (losses) on investment securities $ 968 $ (32,849) The proceeds and gross realized gains and losses on the disposition of securities held in the NDT and coal mine reclamation trusts are shown in the following table. Realized gains and losses are determined by specific identification of costs of securities sold. Gross realized losses shown below exclude the (increase)/decrease in realized impairment losses of $1.1 million and $(12.7) million for the three months ended March 31, 2021 and 2020. Three Months Ended March 31, 2021 2020 (In thousands) Proceeds from sales $ 123,596 $ 149,355 Gross realized gains $ 8,692 $ 5,825 Gross realized (losses) $ (3,443) $ (7,035) At March 31, 2021, the available-for-sale debt securities held by PNM, had the following final maturities: Fair Value (In thousands) Within 1 year $ 31,510 After 1 year through 5 years 71,643 After 5 years through 10 years 103,946 After 10 years through 15 years 18,105 After 15 years through 20 years 11,804 After 20 years 34,529 $ 271,537 Fair Value Disclosures The Company determines the fair values of its derivative and other financial instruments based on the hierarchy which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. There are three levels of inputs that may be used to measure fair value. Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date. Level 2 inputs are inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly. Level 3 inputs are unobservable inputs for the asset or liability. For investment securities, Level 2 and Level 3 fair values are provided by fund managers utilizing a pricing service. For Level 2 fair values, the pricing provider predominantly uses the market approach using bid side market values based upon a hierarchy of information for specific securities or securities with similar characteristics. Fair values of Level 2 investments in mutual funds are equal to net asset value. For commodity derivatives, Level 2 fair values are determined based on market observable inputs, which are validated using multiple broker quotes, including forward price, volatility, and interest rate curves to establish expectations of future prices. Credit valuation adjustments are made for estimated credit losses based on the overall exposure to each counterparty. For the Company’s long-term debt, Level 2 fair values are provided by an external pricing service. The pricing service primarily utilizes quoted prices for similar debt in active markets when determining fair value. The valuation of Level 3 investments, when applicable, requires significant judgment by the pricing provider due to the absence of quoted market values, changes in market conditions, and the long-term nature of the assets. The Company has no Level 3 investments as of March 31, 2021 and December 31, 2020. Management of the Company independently verifies the information provided by pricing services. Items recorded at fair value by PNM on the Condensed Consolidated Balance Sheets are presented below by level of the fair value hierarchy along with gross unrealized gains on investments in available-for-sale debt securities: GAAP Fair Value Hierarchy Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Unrealized Gains (In thousands) March 31, 2021 Cash and cash equivalents $ 11,590 $ 11,590 $ — Equity securities: Corporate stocks, common 86,527 86,527 — Corporate stocks, preferred 9,835 3,456 6,379 Mutual funds and other 57,539 57,498 41 Available-for-sale debt securities: U.S. government 58,575 31,193 27,382 $ 388 International government 15,380 — 15,380 1,641 Municipals 47,188 — 47,188 2,080 Corporate and other 150,394 — 150,394 16,334 $ 437,028 $ 190,264 $ 246,764 $ 20,443 December 31, 2020 Cash and cash equivalents $ 6,107 $ 6,107 $ — Equity securities: Corporate stocks, common 85,271 85,271 — Corporate stocks, preferred 9,910 3,608 6,302 Mutual funds and other 58,817 58,762 55 Available-for-sale debt securities: U.S. government 55,839 29,579 26,260 $ 950 International government 16,032 — 16,032 2,537 Municipals 50,139 — 50,139 2,779 Corporate and other 158,000 3 157,997 21,121 $ 440,115 $ 183,330 $ 256,785 $ 27,387 The carrying amounts and fair values of long-term debt, all of which are considered Level 2 fair value measurements and are not recorded at fair value on the Condensed Consolidated Balance Sheets, are presented below: Carrying Amount Fair Value March 31, 2021 (In thousands) PNMR $ 3,215,692 $ 3,157,858 PNM $ 1,697,195 $ 1,561,816 TNMP $ 853,639 $ 931,042 December 31, 2020 PNMR $ 3,295,150 $ 3,355,761 PNM $ 1,696,620 $ 1,602,547 TNMP $ 853,673 $ 1,006,722 The carrying amount and fair value of the Company’s other investments presented on the Condensed Consolidated Balance Sheets are not material and not shown in the above table.

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2021
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation	Stock-Based Compensation PNMR has various stock-based compensation programs, including stock options, restricted stock, and performance shares granted under the Performance Equity Plan (“PEP”). Although certain PNM and TNMP employees participate in the PNMR plans, PNM and TNMP do not have separate employee stock-based compensation plans. The Company has not awarded stock options since 2010 and all employee stock options expired or were exercised as of February 2020. Certain restricted stock awards are subject to achieving performance or market targets. Other awards of restricted stock are only subject to time vesting requirements. Additional information concerning stock-based compensation under the PEP is contained in Note 12 of the Notes to Consolidated Financial Statements in the 2020 Annual Reports on Form 10-K. Restricted stock under the PEP refers to awards of stock subject to vesting, performance, or market conditions rather than to shares with contractual post-vesting restrictions. Generally, the awards vest ratably over three years from the grant date of the award. However, awards with performance or market conditions vest upon satisfaction of those conditions. In addition, plan provisions provide that upon retirement, participants become 100% vested in certain stock awards. The vesting period for awards of restricted stock to non-employee members of the Board is one-year. The stock-based compensation expense related to restricted stock awards without performance or market conditions to participants that are retirement eligible on the grant date is recognized immediately at the grant date and is not amortized. Compensation expense for other such awards is amortized over the shorter of the requisite vesting period or the period until the participant becomes retirement eligible. Compensation expense for performance-based shares is recognized ratably over the performance period as required service is provided and is adjusted periodically to reflect the level of achievement expected to be attained. Compensation expense related to market-based shares is recognized ratably over the measurement period, regardless of the actual level of achievement, provided the employees meet their service requirements. At March 31, 2021, PNMR had unrecognized expense related to stock awards of $6.7 million, which is expected to be recognized over an average of 2.1 years. PNMR receives a tax deduction for certain stock option exercises during the period the options are exercised, generally for the excess of the price at which the options are sold over the exercise prices of the options, and a tax deduction for the value of restricted stock at the vesting date. All excess tax benefits and deficiencies are recorded to tax expense and classified as operating cash flows when used to reduce income taxes payable. See Note 14. The grant date fair value for restricted stock and stock awards with internal Company performance targets is determined based on the market price of PNMR common stock on the date of the agreements reduced by the present value of future dividends that will not be received prior to vesting. The grant date fair value is applied to the total number of shares that are anticipated to vest, although the number of performance shares that ultimately vest cannot be determined until after the performance periods end. The grant date fair value of stock awards with market targets is determined using Monte Carlo simulation models, which provide grant date fair values that include an expectation of the number of shares to vest at the end of the measurement period. The following table summarizes the weighted-average assumptions used to determine the awards grant date fair value: Three Months Ended March 31, Restricted Shares and Performance Based Shares 2021 2020 Expected quarterly dividends per share $ 0.3275 $ 0.3075 Risk-free interest rate 0.32 % 0.72 % Market-Based Shares Dividend yield 2.76 % 2.51 % Expected volatility 33.69 % 19.41 % Risk-free interest rate 0.29 % 0.72 % The following table summarizes activity in restricted stock awards, including performance-based and market-based shares for the three months ended March 31, 2021: Restricted Stock Shares Weighted- Outstanding at December 31, 2020 168,061 $ 40.77 Granted 194,075 43.68 Exercised (189,098) 42.26 Forfeited (851) 43.77 Outstanding at March 31, 2021 172,187 $ 42.41 PNMR’s current stock-based compensation program provides for performance and market targets through 2023. Included in the above table are 124,941 previously awarded shares that were earned for the 2018-2020 performance measurement period and ratified by the Board in February 2021 (based upon achieving market and performance targets at near "maximum" levels). Excluded from the table above are 142,080, 142,047 and 152,414 shares for the three-year performance periods ending in 2021, 2022 and 2023 that will be awarded if all performance and market criteria are achieved at maximum levels and all executives remain eligible. The following table provides additional information concerning restricted stock activity, including performance-based and market-based shares, and stock options: Three Months Ended March 31, Restricted Stock 2021 2020 Weighted-average grant date fair value $ 43.68 $ 36.88 Total fair value of restricted shares that vested (in thousands) $ 8,967 $ 11,269 Stock Options Total intrinsic value of options exercised (in thousands) $ — $ 84

Financing

Financing	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Financing	FinancingThe Company’s financing strategy includes both short-term and long-term borrowings. The Company utilizes short-term revolving credit facilities, as well as cash flows from operations, to provide funds for both construction and operating expenditures. Depending on market and other conditions, the Company will periodically sell long-term debt or enter into term loan arrangements and use the proceeds to reduce borrowings under the revolving credit facilities or refinance other debt. Each of the Company’s revolving credit facilities and term loans contains a single financial covenant that requires the maintenance of a debt-to-capitalization ratio. For the PNMR and PNMR Development agreements this ratio must be maintained at less than or equal to 70%, and for the PNM and TNMP agreements this ratio must be maintained at less than or equal to 65%. The Company’s revolving credit facilities and term loans generally also contain customary covenants, events of default, cross-default provisions, and change-of-control provisions. PNM must obtain NMPRC approval for any financing transaction having a maturity of more than 18 months. In addition, PNM files its annual informational financing filing and short-term financing plan with the NMPRC. Additional information concerning financing activities is contained in Note 7 of the Notes to Consolidated Financial Statements in the 2020 Annual Reports on Form 10-K. Financing Activities In August 2020, PNMR entered into letter of credit arrangements with Wells Fargo Bank, N.A. (the "WFB LOC Facility") under which letters of credit aggregating $30.3 million were issued to facilitate the posting of reclamation bonds currently held by WSJ LLC (who assumed all the obligations of SJCC post-bankruptcy). The reclamation bonds were required to be posted in connection with permits relating to the operation of the San Juan mine. On March 9, 2018, PNMR issued $300.0 million aggregate principal amount of 3.25% SUNs (the “PNMR 2018 SUNs”), which matured on March 9, 2021. The proceeds from the offering were used to repay the $150.0 million PNMR 2015 Term Loan that was due on March 9, 2018 and to reduce borrowings under the PNMR Revolving Credit Facility. On December 22, 2020, PNMR entered into the $300.0 million PNMR 2020 Delayed-Draw Term Loan that matures in January 2022 and drew $80.0 million to refinance existing indebtedness and for other corporate purposes. On March 9, 2021, PNMR utilized the remaining $220.0 million of capacity under the PNMR 2020 Delayed-Draw Term Loan to repay an equivalent amount of the PNMR 2018 SUNs. The remaining $80.0 million repayment of the PNMR 2018 SUNs was funded through borrowings under the PNMR Revolving Credit Facility. On October 20, 2020, the execution of the Merger Agreement constituted a “Change of Control” under certain PNMR, TNMP and PNMR Development debt agreements. Under each of the specified debt agreements, a “Change of Control” constitutes an “Event of Default,” pursuant to which the lender parties thereto have the right to accelerate the indebtedness under the debt agreements. The definition of Change of Control under the PNM debt agreements and PNM note purchase agreements was not triggered by the execution of the Merger Agreement. On October 26, 2020, PNMR, TNMP and PNMR Development entered into amendment agreements with the lender parties thereto to amend the definition of "Change of Control" such that the entry into the Merger Agreement would not constitute a Change of Control and to waive the Event of Default arising from entry into the Merger Agreement. The amended Change of Control definition under the PNMR, TNMP, and PNMR Development debt agreements will, however, be triggered again upon the closing of the Merger. Prior to the closing of the Merger, the Company intends to coordinate with the lenders and Avangrid to either amend the definition of Change of Control permitting Avangrid ownership of the Company; or to refinance or enter into new debt agreements that would include Avangrid as an owner of the Company. The Change of Control provisions in the PNM debt agreements and PNM note purchase agreements are not triggered by the close of the Merger. The documents governing TNMP's aggregate $750.0 million of outstanding First Mortgage Bonds ("TNMP FMBs") obligated TNMP to offer, within 30 business days following the signing of the Merger Agreement, to prepay all $750.0 million outstanding TNMP FMBs at 100% of the principal amount, plus accrued and unpaid interest thereon, but without any make-whole amount or other premium. TNMP made such offer to prepay the TNMP FMBs in accordance with the terms of the TNMP FMBs, and none of the holders of the TNMP FMBs accepted TNMP’s offer. The documents governing the TNMP FMBs require TNMP to make another offer, within 30 business days of closing of the Merger, to prepay all outstanding TNMP FMBs at par. TNMP will make such offer to prepay the TNMP FMBs in accordance with the terms of the TNMP FMBs; however, holders of the TNMP FMBs are not required to tender their TNMP FMBs and may accept or reject such offer to prepay. The information in this Quarterly Report on Form 10-Q is for informational purposes only and is neither an offer to purchase, nor a solicitation of an offer to sell, subscribe for or buy any securities in any jurisdiction pursuant to the proposed transactions or otherwise, nor shall there be any sale, issuance or transfer of securities in any jurisdiction in contravention of applicable law. Similar to the offer to prepay made after signing the Merger Agreement, the post-Merger closing offer to prepay the TNMP FMBs will be made only pursuant to an offer to prepay, which will set forth the terms and conditions of the offer to prepay. At March 31, 2021, variable interest rates were 1.07% on the PNMR 2019 Term Loan that matures in June 2021, 1.21% on the PNMR 2020 Term Loan that matures in January 2022, 1.36% on the PNMR 2020 Delayed-Draw Term Loan that matures in January 2022, 0.76% on the PNM 2019 $40.0 million Term Loan that matures in June 2021, 0.14% on the PNM Floating Rate PCRBs in the weekly mode, and 1.48% on the PNMR Development Term Loan that matures in January 2022. Short-term Debt and Liquidity Currently, the PNMR Revolving Credit Facility has a financing capacity of $300.0 million and the PNM Revolving Credit Facility has a financing capacity of $400.0 million. Both facilities currently expire on October 31, 2023 and contain options to be extended through October 2024, subject to approval by a majority of the lenders. PNM also has the $40.0 million PNM 2017 New Mexico Credit Facility that expires on December 12, 2022. The TNMP Revolving Credit Facility is a $75.0 million revolving credit facility secured by $75.0 million aggregate principal amount of TNMP first mortgage bonds that matures on September 23, 2022 and contains two one-year extension options, subject to approval by a majority of the lenders. PNMR Development has a $40.0 million revolving credit facility that expires on January 31, 2022. PNMR Development has the option to further increase the capacity of this facility to $50.0 million upon 15-days advance notice, subject to approval by the lender. The PNMR Development Revolving Credit Facility bears interest at a variable rate and contains terms similar to the PNMR Revolving Credit Facility. PNMR has guaranteed the obligations of PNMR Development under the facility. PNMR Development uses the facility to finance its participation in NMRD and for other activities. Variable interest rates under these facilities are based on LIBOR but contain provisions which allow for the replacement of LIBOR with other widely accepted interest rates. Short-term debt outstanding consists of: March 31, December 31, Short-term Debt 2021 2020 (In thousands) PNM: PNM Revolving Credit Facility $ — $ — PNM 2017 New Mexico Credit Facility — 10,000 — 10,000 TNMP Revolving Credit Facility 43,100 — PNMR: PNMR Revolving Credit Facility 114,400 12,000 PNMR Development Revolving Credit Facility 40,000 10,000 $ 197,500 $ 32,000 At March 31, 2021, the weighted average interest rate was 1.61% for the PNMR Revolving Credit Facility, 1.11% for the PNMR Development Revolving Credit Facility, and 0.86% for the TNMP Revolving Credit Facility. There were no borrowings outstanding under the PNM 2017 New Mexico Revolving Credit Facility at March 31, 2021. In addition to the above borrowings, PNMR, PNM, and TNMP had letters of credit outstanding of $3.4 million, $2.2 million, and zero at March 31, 2021 that reduce the available capacity under their respective revolving credit facilities. The above table excludes intercompany debt. As of March 31, 2021 and December 31, 2020, neither PNM nor TNMP had any intercompany borrowings from PNMR. PNMR had $32.4 million and zero in intercompany borrowings from PNMR Development at March 31, 2021 and December 31, 2020. PNMR Development had zero and $0.3 million in intercompany borrowings from PNMR at March 31, 2021 and December 31, 2020. In 2017, PNMR entered into three separate four-year hedging agreements whereby it effectively established fixed interest rates of 1.926%, 1.823%, and 1.629%, plus customary spreads over LIBOR for three separate tranches, each of $50.0 million, of its variable rate debt. On March 23, 2021 the 1.926% fixed interest rate hedge agreement expired according to its terms and the remaining agreements are expected to expire in May 2021. The hedge agreements are accounted for as cash flow hedges and had fair values of $0.3 million and $0.9 million at March 31, 2021 and December 31, 2020 that are included in other current liabilities on the Condensed Consolidated Balance Sheets. As discussed in Note 3, changes in the fair value of the cash flow hedges are deferred in AOCI and amounts reclassified to the Condensed Consolidated Statement of Earnings are recorded in interest charges. The fair values were determined using Level 2 inputs under the fair value hierarchy, including using forward LIBOR curves under the mid-market convention to discount cash flows over the remaining term of the agreement. At April 23, 2021, PNMR, PNM, TNMP, and PNMR Development had availability of $184.4 million, $395.9 million, $24.5 million, and zero under their respective revolving credit facilities, including reductions of availability due to outstanding letters of credit. PNM had $40.0 million of availability under the PNM 2017 New Mexico Credit Facility. Total availability at April 23, 2021, on a consolidated basis, was $644.8 million for PNMR. Availability under PNM's Revolving Credit Facility and total availability at PNMR, on a consolidated basis, does not reflect a reduction of $100.3 million that PNM has reserved to provide liquidity support for the PNM Floating Rate PCRBs. As of April 23, 2021, PNM, TNMP, and PNMR Development had no borrowings from PNMR under their intercompany loan agreements however, PNMR had $32.4 million in borrowings from PNMR Development. At April 23, 2021, PNMR, PNM, and TNMP had invested cash of $0.9 million, zero, and zero. The Company’s debt arrangements have various maturities and expiration dates. The PNM 2019 $40.0 million Term Loan matures in June 2021. In addition, PNM has $146.0 million of PCRBs that must be repriced and $160.0 million of SUNs that mature in October 2021, with an option to repay the SUNs at par as early as July 1, 2021. The $150.0 million PNMR 2019 Term Loan matures in June 2021. The $150.0 million PNMR 2020 Term Loan, the $300.0 million PNMR 2020 Delayed-Draw Term Loan, and the $65.0 million PNMR Development Term Loan all mature in January 2022. Additional information on debt maturities is contained in Note 7 of the Notes to Consolidated Financial Statements in the 2020 Annual Reports on Form 10-K.

Pension and Other Postretiremen

Pension and Other Postretirement Benefit Plans	3 Months Ended
	Mar. 31, 2021
Retirement Benefits [Abstract]
Pension and Other Postretirement Benefit Plans	Pension and Other Postretirement Benefit Plans PNMR and its subsidiaries maintain qualified defined benefit pension plans, postretirement benefit plans providing medical and dental benefits, and executive retirement programs (collectively, the “PNM Plans” and “TNMP Plans”). PNMR maintains the legal obligation for the benefits owed to participants under these plans. The periodic costs or income of the PNM Plans and TNMP Plans are included in regulated rates to the extent attributable to regulated operations. The Company presents the service cost component of its net periodic benefit costs in administrative and general expenses and the non-service costs components in other income (deductions), net of amounts capitalized or deferred to regulatory assets and liabilities, on the Condensed Consolidated Statements of Earnings. PNM and TNMP receive a regulated return on the amounts funded for pension and OPEB plans in excess of accumulated periodic cost or income to the extent included in retail rates (a “prepaid pension asset”). Additional information concerning pension and OPEB plans is contained in Note 11 of the Notes to Consolidated Financial Statements in the 2020 Annual Reports on Form 10-K. Annual net periodic benefit cost for the plans is actuarially determined using the methods and assumptions set forth in that note and is recognized ratably throughout the year. Differences between TNMP's annual net periodic costs (income) and amounts included in its regulated rates are deferred to regulatory assets or liabilities, for recovery or refund in future rate proceedings. PNM Plans The following table presents the components of the PNM Plans’ net periodic benefit cost: Three Months Ended March 31, Pension Plan OPEB Plan Executive Retirement Program 2021 2020 2021 2020 2021 2020 (In thousands) Components of Net Periodic Benefit Cost Service cost $ — $ — $ 6 $ 10 $ — $ — Interest cost 4,036 4,985 477 613 90 122 Expected return on plan assets (7,133) (7,363) (1,042) (1,387) — — Amortization of net loss 4,541 4,465 — 87 100 101 Amortization of prior service cost — (138) — — — — Net Periodic Benefit Cost (Income) $ 1,444 $ 1,949 $ (559) $ (677) $ 190 $ 223 PNM did not make any contributions to its pension plan trust in the three months ended March 31, 2021 and 2020 and does not anticipate making any contributions to the pension plan in 2021 or 2022 but expects to contribute $10.8 million in 2023, $11.5 million in 2024, and $10.6 million in 2025 based on current law, funding requirements, and estimates of portfolio performance. Funding assumptions were developed using a discount rate of 2.9%. Actual amounts to be funded in the future will be dependent on the actuarial assumptions at that time, including the appropriate discount rate. PNM may make additional contributions at its discretion. PNM did not make any cash contributions to the OPEB trust in the three months ended March 31, 2021 and 2020, however, a portion of the disbursements attributable to the OPEB trust are paid by PNM and are therefore considered to be contributions to the OPEB plan. Payments by PNM on behalf of the PNM OPEB plan were $0.9 million and $1.1 million in the three months ended March 31, 2021 and 2020. These payments are expected to total $3.3 million in 2021 and $13.1 million for 2022-2025. Disbursements under the executive retirement program, which are funded by PNM and considered to be contributions to the plan, were $0.4 million and $0.3 million in the three months ended March 31, 2021 and 2020 and are expected to total $1.3 million during 2021 and $4.9 million for 2022-2025. TNMP Plans The following table presents the components of the TNMP Plans’ net periodic benefit cost: Three Months Ended March 31, Pension Plan OPEB Plan Executive Retirement Program 2021 2020 2021 2020 2021 2020 (In thousands) Components of Net Periodic Benefit Cost Service cost $ — $ — $ 11 $ 12 $ — $ — Interest cost 435 544 77 93 4 6 Expected return on plan assets (795) (821) (102) (134) — — Amortization of net (gain) loss 312 315 (80) (81) 9 6 Amortization of prior service cost — — — — — — Net Periodic Benefit Cost (Income) $ (48) $ 38 $ (94) $ (110) $ 13 $ 12

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Overview There are various claims and lawsuits pending against the Company. In addition, the Company is subject to federal, state, and local environmental laws and regulations and periodically participates in the investigation and remediation of various sites. In addition, the Company periodically enters into financial commitments in connection with its business operations. Also, the Company is involved in various legal and regulatory proceedings in the normal course of its business. See Note 12. It is not possible at this time for the Company to determine fully the effect of all litigation and other legal and regulatory proceedings on its financial position, results of operations, or cash flows. With respect to some of the items listed below, the Company has determined that a loss is not probable or that, to the extent probable, cannot be reasonably estimated. In some cases, the Company is not able to predict with any degree of certainty the range of possible loss that could be incurred. The Company assesses legal and regulatory matters based on current information and makes judgments concerning their potential outcome, giving due consideration to the nature of the claim, the amount and nature of any damages sought, and the probability of success. Such judgments are made with the understanding that the outcome of any litigation, investigation, or other legal proceeding is inherently uncertain. The Company records liabilities for matters where it is probable a loss has been incurred and the amount of loss is reasonably estimable. The actual outcomes of the items listed below could ultimately differ from the judgments made and the differences could be material. The Company cannot make any assurances that the amount of reserves or potential insurance coverage will be sufficient to cover the cash obligations that might be incurred as a result of litigation or regulatory proceedings. Except as otherwise disclosed, the Company does not expect that any known lawsuits, environmental costs, and commitments will have a material effect on its financial condition, results of operations, or cash flows. Additional information concerning commitments and contingencies is contained in Note 16 of the Notes to Consolidated Financial Statements in the 2020 Annual Reports on Form 10-K. Commitments and Contingencies Related to the Environment Nuclear Spent Fuel and Waste Disposal Nuclear power plant operators are required to enter into spent fuel disposal contracts with the DOE that require the DOE to accept and dispose of all spent nuclear fuel and other high-level radioactive wastes generated by domestic power reactors. Although the Nuclear Waste Policy Act required the DOE to develop a permanent repository for the storage and disposal of spent nuclear fuel by 1998, the DOE announced that it would not be able to open the repository by 1998 and sought to excuse its performance of these requirements. In November 1997, the DC Circuit issued a decision preventing the DOE from excusing its own delay but refused to order the DOE to begin accepting spent nuclear fuel. Based on this decision and the DOE’s delay, a number of utilities, including APS (on behalf of itself and the other PVNGS owners, including PNM), filed damages actions against the DOE in the Court of Federal Claims. The lawsuits filed by APS alleged that damages were incurred due to DOE’s continuing failure to remove spent nuclear fuel and high-level waste from PVNGS. In August 2014, APS and the DOE entered into a settlement agreement that establishes a process for the payment of claims for costs incurred through December 31, 2019. In July 2020, APS accepted the DOE's extension of the settlement agreement for recovery of costs incurred through December 31, 2022. Under the settlement agreement, APS must submit claims annually for payment of allowable costs. PNM records estimated claims on a quarterly basis. The benefit from the claims is passed through to customers under the FPPAC to the extent applicable to NMPRC regulated operations. PNM estimates that it will incur approximately $59.6 million (in 2019 dollars) for its share of the costs related to the on-site interim storage of spent nuclear fuel at PVNGS during the term of the operating licenses. PNM accrues these costs as a component of fuel expense as the nuclear fuel is consumed. At both March 31, 2021 and December 31, 2020, PNM had a liability for interim storage costs of $12.8 million, which is included in other deferred credits. PVNGS has sufficient capacity at its on-site Independent Spent Fuel Storage Installation (“ISFSI”) to store all of the nuclear fuel that will be irradiated during the initial operating license period, which ends in December 2027. Additionally, PVNGS has sufficient capacity at its on-site ISFSI to store a portion of the fuel that will be irradiated during the period of extended operation, which ends in November 2047. If uncertainties regarding the U.S. government’s obligation to accept and store spent fuel are not favorably resolved, APS will evaluate alternative storage solutions that may obviate the need to expand the ISFSI to accommodate all of the fuel that will be irradiated during the period of extended operation. The Energy Transition Act In 2019, the Governor signed into New Mexico state law Senate Bill 489, known as the Energy Transition Act (“ETA”). The ETA became effective as of June 14, 2019 and sets a statewide standard that requires investor-owned electric utilities to have specified percentages of their electric-generating portfolios be from renewable and zero-carbon generating resources. The ETA amends the REA and requires utilities operating in New Mexico to have renewable portfolios equal to 40% by 2025, 50% by 2030, 80% by 2040, and 100% zero-carbon energy by 2045. The ETA also amends sections of the REA to allow for the recovery of undepreciated investments and decommissioning costs related to qualifying EGUs that the NMPRC has required be removed from retail jurisdictional rates, provided replacement resources to be included in retail rates have lower or zero-carbon emissions. The ETA requires the NMPRC to review and approve utilities’ annual renewable portfolio plans to ensure compliance with the RPS. The ETA also directs the New Mexico Environmental Improvement Board to adopt standards of performance that limit CO 2 emissions to no more than 1,100 lbs. per MWh beginning January 1, 2023 for new or existing coal-fired EGUs with original installed capacities exceeding 300 MW. The ETA provides for a transition from fossil-fuel generation resources to renewable and other carbon-free resources through certain provisions relating to the abandonment of coal-fired generating facilities. These provisions include the use of energy transition bonds, which are designed to be highly rated bonds that can be issued to finance certain costs of abandoning coal-fired facilities that are retired prior to January 1, 2023 for facilities operated by a “qualifying utility,” or prior to January 1, 2032 for facilities that are not operated by a qualifying utility. The amount of energy transition bonds that can be issued to recover abandonment costs is limited to the lesser of $375.0 million or 150% of the undepreciated investment of the facility as of the abandonment date. Proceeds provided by energy transition bonds must be used only for purposes related to providing utility service to customers and to pay energy transition costs (as defined by the ETA). These costs may include plant decommissioning and coal mine reclamation costs provided those costs have not previously been recovered from customers or disallowed by the NMPRC or by a court order. Proceeds from energy transition bonds may also be used to fund severances for employees of the retired facility and related coal mine and to promote economic development, education and job training in areas impacted by the retirement of the coal-fired facilities. Energy transition bonds must be issued under a NMPRC-approved financing order, are secured by “energy transition property,” are non-recourse to the issuing utility, and repaid by a non-bypassable charge paid by all customers of the issuing utility. These customer charges are subject to an adjustment mechanism designed to provide for timely and complete payment of principal and interest due under the energy transition bonds. The ETA also provides that utilities must obtain NMPRC approval of competitively procured replacement resources that shall be evaluated based on their cost, economic development opportunity, ability to provide jobs with comparable pay and benefits to those lost upon retirement of the facility, and that do not exceed emissions thresholds specified in the ETA. In determining whether to approve replacement resources, the NMPRC must give preference to resources with the least environmental impacts, those with higher ratios of capital costs to fuel costs, and those located in the school district of the abandoned facility. The ETA also provides for the procurement of energy storage facilities and gives utilities discretion to maintain, control, and operate these systems to ensure reliable and efficient service. The ETA will have a significant impact on PNM’s future generation portfolio, including PNM’s planned retirement of SJGS in 2022 and the planned Four Corners exit in 2024. PNM cannot predict the full impact of the ETA or the outcome of its pending and potential future generating resource abandonment and replacement resource filings with the NMPRC. See additional discussion in Note 12 of PNM’s SJGS and Four Corners Abandonment Applications. The Clean Air Act Regional Haze In 1999, EPA developed a regional haze program and regional haze rules under the CAA. The rule directs each of the 50 states to address regional haze. Pursuant to the CAA, states are required to establish goals for improving visibility in national parks and wilderness areas (also known as Class I areas) and to develop long-term strategies for reducing emissions of air pollutants that cause visibility impairment in their own states and for preventing degradation in other states. States must establish a series of interim goals to ensure continued progress by adopting a new SIP every ten years. In the first SIP planning period, states were required to conduct BART determinations for certain covered facilities, including utility boilers, built between 1962 and 1977 that have the potential to emit more than 250 tons per year of visibility impairing pollution. If it was demonstrated that the emissions from these sources caused or contributed to visibility impairment in any Class I area, BART must have been installed by the beginning of 2018. For all future SIP planning periods, states must evaluate whether additional emissions reduction measures may be needed to continue making reasonable progress toward natural visibility conditions. In 2017, EPA published revisions to the regional haze rule in the Federal Register. EPA also provided a companion draft guidance document for public comment. The new rule delayed the due date for the next cycle of SIPs from 2019 to 2021, altered the planning process that states must employ in determining whether to impose “reasonable progress” emission reduction measures, and gave new authority to federal land managers to seek additional emission reduction measures outside of the states’ planning process. Finally, the rule made several procedural changes to the regional haze program, including changes to the schedule and process for states to file 5-year progress reports. EPA’s new rule was challenged by numerous parties. On January 19, 2018, EPA filed a motion to hold the case in abeyance in light of several letters issued by EPA on January 17, 2018 to grant various petitions for reconsideration of the 2017 rule revisions. EPA’s decision to revisit the 2017 rule is not a determination on the merits of the issues raised in the petitions. On December 20, 2018, EPA released a new guidance document on tracking visibility progress for the second planning period. EPA is allowing states discretion to develop SIPs that may differ from EPA’s guidance as long as they are consistent with the CAA and other applicable regulations. On August 20, 2019, EPA finalized the draft guidance that was released in 2016 as a companion to the regional haze rule revisions. The final guidance differs from the draft in several ways but is likely to be reconsidered by the Biden Administration. SIPs for the second planning period are due in July 2021. NMED is currently preparing its SIP for the second compliance period and has notified PNM that it will not be required to submit a regional haze four-factor analysis for SJGS since PNM will retire its share of SJGS in 2022. PNM cannot predict the outcome of these matters with respect to Four Corners. Carbon Dioxide Emissions On August 3, 2015, EPA established standards to limit CO 2 emissions from power plants. EPA took three separate but related actions in which it: (1) established the Carbon Pollution Standards for new, modified, and reconstructed power plants; (2) established the Clean Power Plan to set standards for carbon emission reductions from existing power plants; and (3) released a proposed federal plan associated with the final Clean Power Plan. The Clean Power Plan was published on October 23, 2015. Multiple states, utilities, and trade groups filed petitions for review in the DC Circuit to challenge both the Carbon Pollution Standards for new sources and the Clean Power Plan for existing sources. Challengers successfully petitioned the US Supreme Court for a stay of the Clean Power Plan. However, before the DC Circuit could issue an opinion regarding either the Carbon Pollution Standards or the Clean Power Plan, the Trump Administration asked that the case be held in abeyance while the rule was being re-evaluated, which was granted. On June 19, 2019, EPA repealed the Clean Power Plan, promulgated the ACE Rule, and revised the implementing regulations for all emission guidelines. EPA set the Best System of Emissions Reduction ("BSER") for existing coal-fired power plants as heat rate efficiency improvements based on a range of "candidate technologies" that can be applied inside the fence-line. Rather than setting a specific numerical standard of performance, EPA's rule directed states to determine which of the candidate technologies to apply to each coal-fired unit and establish standards of performance based on the degree of emission reduction achievable based on the application of BSER. On September 17, 2019, the DC Circuit issued an order that granted motions by various petitioners, including industry groups and EPA, to dismiss the cases challenging the Clean Power Plan as moot due to EPA’s issuance of the ACE Rule. However, on January 19, 2021, the DC Circuit issued an opinion in American Lung Association and American Public Health Association v. EPA, et al. regarding challenges to the ACE Rule. The DC Circuit vacated the ACE Rule and remanded the record back to the EPA for further consideration consistent with its opinion, finding that EPA misinterpreted the CAA when it determined that the language of section 111 unambiguously barred consideration of emissions reductions options that were not applied at the source. An appeal via petitions for certiorari to the US Supreme Court will remain available until June 2021. While the DC Circuit did not uphold the ACE Rule, it did not reinstate the Clean Power Plan. EPA filed a motion seeking a partial stay of the mandate as to the repeal of the Clean Power Plan, to ensure the court’s order will not render effective the now out-of-date Clean Power Plan. On February 22, 2021, the U.S. Court of Appeals for the DC Circuit granted EPA’s motion, indicating that it would withhold issuance of the mandate with respect to the repeal of the Clean Power Plan until EPA responds to the court’s remand in a new rulemaking action. The litigation over the Carbon Pollution Standards remains held in abeyance but could be reactivated by the parties upon a determination by the court that the Biden Administration is unlikely to finalize the revisions proposed in 2018 and that reconsideration of the rule has concluded. While corresponding NSR reform regulations were proposed as part of the proposed ACE Rule, the final rule did not include such reform measures. Unrelated to the ACE Rule, EPA issued a proposed rule on August 1, 2019, to clarify one aspect of the pre-construction review process for evaluating whether the NSR permitting program would apply to a proposed project at an existing source of emissions. The final rule on NSR Project Emissions Accounting became effective on December 24, 2020, clarifying that both emissions increases and decreases resulting from a project are to be considered in determining whether the proposed project will result in an increase in air emissions. However, the rule may be reconsidered by the Biden Administration. On January 27, 2021, President Biden signed an extensive Executive Order aimed at addressing climate change concerns domestically and internationally. The order is intended to build on the initial climate-related actions the Biden Administration took on January 20, 2021. It addresses a wide range of issues, including establishing climate change concerns as an essential element of U.S. foreign and security policy, identifying a process to determine the U.S. INDC under the Paris Agreement, and establishing a Special Presidential Envoy for Climate that will sit on the National Security Council. On April 22, 2021, at the Earth Day Summit, as part of the U.S.’s re-entry into the Paris Agreement, President Biden unveiled the goal to cut U.S. emissions by 50% - 52% from 2005 levels by 2030, nearly double the GHG emissions reduction target set by the Obama Administration. The 2030 goal joins President Biden’s other climate goals which include a carbon pollution-free power sector by 2035 and a net-zero emissions economy by no later than 2050. PNM’s review of the GHG emission reductions standards that may occur as a result of legislation or regulation under the Biden Administration and in response to the court's ruling on the ACE Rule is ongoing. PNM cannot predict the impact these standards may have on its operations or a range of the potential costs of compliance, if any. National Ambient Air Quality Standards (“NAAQS”) The CAA requires EPA to set NAAQS for pollutants reasonably anticipated to endanger public health or welfare. EPA has set NAAQS for certain pollutants, including NOx, SO 2 , ozone, and particulate matter. NOx Standard – On April 18, 2018, EPA published the final rule to retain the current primary health-based NOx standards of which NO 2 is the constituent of greatest concern and is the indicator for the primary NAAQS. EPA concluded that the current 1-hour and annual primary NO 2 standards are requisite to protect public health with an adequate margin of safety. The rule became effective on May 18, 2018. SO 2 Standard – On May 13, 2014, EPA released the draft data requirements rule for the 1-hour SO 2 NAAQS, which directs state and tribal air agencies to characterize current air quality in areas with large SO 2 sources to identify maximum 1-hour SO 2 concentrations. This characterization requires areas be designated as attainment, nonattainment, or unclassifiable for compliance with the 1-hour SO 2 NAAQS. On August 11, 2015, EPA released the Data Requirements Rule for SO 2 , telling states how to model or monitor to determine attainment or nonattainment with the new 1-hour SO 2 NAAQS. NMED submitted the first annual report for SJGS as required by the Data Requirements Rule in June 2018. That report recommended that no further modeling was warranted due to decreased SO 2 emissions. NMED submitted the second and third annual modeling report to EPA in July 2019 and July 2020. Those reports retained the recommendation that no further modeling is needed at this time and is subject to EPA review. On February 25, 2019, EPA announced its final decision to retain without changes the primary health-based NAAQS for SO 2 . Specifically, EPA will retain the current 1-hour standard for SO 2 , which is 75 parts per billion, based on the 3-year average of the 99th percentile of daily maximum 1-hour SO 2 concentrations. On March 26, 2021, EPA published in the Federal Register the initial air quality designations for all remaining areas not yet designated under the 2010 SO2 Primary NAAQS. This is EPA’s fourth and final set of actions to designate areas of the U.S. for the 2010 SO2 NAAQS. All areas of New Mexico have been designated attainment/unclassifiable through four rounds of designations by the EPA. Ozone Standard – On October 1, 2015, EPA finalized the new ozone NAAQS and lowered both the primary and secondary 8-hour standard from 75 to 70 parts per billion. With ozone standards becoming more stringent, fossil-fueled generation units will come under increasing pressure to reduce emissions of NOx and volatile organic compounds since these are the pollutants that form ground-level ozone. On July 13, 2020, EPA proposed to retain the existing ozone NAAQS based on a review of the full body of currently available scientific evidence and exposure/risk information. EPA finalized its decision to retain the ozone NAAQS in a notice published on December 31, 2020 making it immediately effective. The Center for Biological Diversity filed a lawsuit on February 25, 2021, challenging the decision to retain the existing ozone standard, and the Biden Administration has included the decision in its list of actions that may be reconsidered. On November 10, 2015, EPA proposed a rule revising its Exceptional Events Rule, which outlines the requirements for excluding air quality data (including ozone data) from regulatory decisions if the data is affected by events outside an area’s control. The proposed rule is important in light of the more stringent ozone NAAQS final rule since western states like New Mexico and Arizona are subject to elevated background ozone transport from natural local sources, such as wildfires and stratospheric inversions, and transported via winds from distant sources in other regions or countries. EPA finalized the rule on October 3, 2016 and released related guidance in 2018 and 2019 to help implement its new exceptional events policy. During 2017 and 2018, EPA released rules establishing area designations for ozone. In those rules, San Juan County, New Mexico, where SJGS and Four Corners are located, is designated as attainment/unclassifiable and only a small area in Doña Ana County, New Mexico is designated as marginal non-attainment. Although Afton is located in Doña Ana County, it is not located within the small area designated as non-attainment for the 2015 ozone standard. The rule became effective May 8, 2018. Attainment plans for non-attainment areas are due in August 2021. NMED has responsibility for bringing the small area in Doña Ana County designated as marginal/non-attainment for ozone into compliance and will look at all sources of NOx and volatile organic compounds. On November 22, 2019, EPA issued findings that several states, including New Mexico, had failed to submit SIPs for the 8-hour ozone NAAQS. In response, in December 2019, NMED published the Public Review Draft of the New Mexico 2013 NAAQS Good Neighbor SIP that outlines the strategies and emissions control measures that are expected to improve air quality in the area by May 8, 2021. These strategies and measures would aim to reduce the amount of NOx and volatile organic compounds emitted to the atmosphere and will rely upon current or upcoming federal rules, new or revised state rules, and other programs. Comments or requests for a public hearing were required by January 21, 2020. NMED Air Quality Bureau has completed a draft retrospective demonstration showing that this area would be in attainment of the NAAQS but for international emissions. This demonstration allows the area to maintain a marginal non-attainment status and eliminates the need for additional planning requirements and emission reductions. NMED is seeking public comment on the draft document through May 14, 2021. PNM does not believe there will be material impacts to its facilities as a result of NMED’s non-attainment designation of the small area within Doña Ana County. Until EPA approves attainment designations for the Navajo Nation and releases a proposal to implement the revised ozone NAAQS, PNM is unable to predict what impact the adoption of these standards may have on Four Corners. PNM cannot predict the outcome of this matter. PM Standard – On January 30, 2020, EPA published in the Federal Register a notice announcing the availability of its final Policy Assessment for the Review of the NAAQS for Particulate Matter (the "Final PA"). The final assessment was prepared as part of the review of the primary and secondary PM NAAQS. In the assessment, EPA recommended lowering the primary annual PM2.5 standard to between 8 µg/m3 and 10 µg/m3. However, on April 30, 2020, EPA published a proposed rule to retain the current standards for PM due to uncertainties in the data relied upon in the Final PA. EPA accepted comments on the proposed rule through June 29, 2020. On December 7, 2020, EPA announced it will retain, without revision, the existing primary (health-based) and secondary (welfare-based) NAAQS for PM, and EPA published a notice of that final action on December 18, 2020, making it immediately effective. On January 14, 2021, several states and New York City filed a petition for review in the DC Circuit, challenging EPA’s final rule retaining the current primary and secondary PM NAAQS. On February 9, 2021, a similar lawsuit was filed by the Center for Biological Diversity in the DC Circuit. The Biden Administration has also included the decision in its list of actions that may be reconsidered. Navajo Nation Environmental Issues Four Corners is located on the Navajo Nation and is held under easements granted by the federal government, as well as agreements with the Navajo Nation which grant each of the owners the right to operate on the site. The Navajo Acts purport to give the Navajo Nation Environmental Protection Agency authority to promulgate regulations covering air quality, drinking water, and pesticide activities, including those activities that occur at Four Corners. In October 1995, the Four Corners participants filed a lawsuit in the District Court of the Navajo Nation challenging the applicability of the Navajo Acts to Four Corners. In May 2005, APS and the Navajo Nation signed an agreement resolving the dispute regarding the Navajo Nation’s authority to adopt operating permit regulations under the Navajo Nation Air Pollution Prevention and Control Act. As a result of this agreement, APS sought, and the court granted, dismissal of the pending litigation in the Navajo Nation Supreme Court and the Navajo Nation District Court, to the extent the claims relate to the CAA. The agreement does not address or resolve any dispute relating to other aspects of the Navajo Acts. PNM cannot currently predict the outcome of these matters or the range of their potential impacts. Cooling Water Intake Structures In 2014, EPA issued a rule establishing national standards for certain cooling water intake structures at existing power plants and other facilities under the Clean Water Act to protect fish and other aquatic organisms by minimizing impingement mortality (the capture of aquatic wildlife on intake structures or against screens) and entrainment mortality (the capture of fish or shellfish in water flow entering and passing through intake structures). To minimize impingement mortality, the rule provides operators of facilities, such as SJGS and Four Corners, seven options for meeting Best Technology Available (“BTA”) standards for reducing impingement. SJGS has a closed-cycle recirculating cooling system, which is a listed BTA and may also qualify for the “ de minimis rate of impingement” based on the design of the intake structure. The permitting authority must establish the BTA for entrainment on a site-specific basis, taking into consideration an array of factors, including endangered species and social costs and benefits. Affected sources must submit source water baseline characterization data to the permitting authority to assist in the determination. Compliance deadlines under the rule are tied to permit renewal and will be subject to a schedule of compliance established by the permitting authority. The rule is not clear as to how it applies and what the compliance timelines are for facilities like SJGS that have a cooling water intake structure and only a multi-sector general stormwater permit. However, EPA has indicated that it is contemplating a December 31, 2023 compliance deadline. PNM is working with EPA regarding this issue and does not expect material changes as a result of any requirements that may be imposed upon SJGS, particularly given the NMPRC's April 1, 2020 approval for PNM to retire its share of SJGS by June 2022. On May 23, 2018, several environmental groups sued EPA Region IX in the United States Court of Appeals for the Ninth Circuit Court over EPA’s failure to timely reissue the Four Corners NPDES permit. The petitioners asked the court to issue a writ of mandamus compelling EPA Region IX to take final action on the pending NPDES permit by a reasonable date. EPA subsequently reissued the NPDES permit on June 12, 2018. The permit did not contain conditions related to the cooling water intake structure rule as EPA determined that the facility has achieved BTA for both impingement and entrainment by operating a closed-cycle recirculation system. On July 16, 2018, several environmental groups filed a petition for review with EPA’s Environmental Appeals Board ("EAB") concerning the reissued permit. The environmental groups alleged that the permit was reissued in contravention of several requirements under the Clean Water Act and did not contain required provisions concerning certain revised effluent limitation guidelines, existing-source regulations governing cooling-water intake structures, and effluent limits for surface seepage and subsurface discharges from coal-ash disposal facilities. On December 19, 2018, EPA withdrew the Four Corners NPDES permit in order to examine issues raised by the environmental groups. Withdrawal of the permit moots the appeal pending before the EAB. EAB thereafter dismissed the environmental groups’ appeal. EPA issued an updated NPDES permit on September 30, 2019. The permit was stayed pending an appeal filed by several environmental groups on November 1, 2019 to EAB. Oral argument was heard on September 3, 2020. The EAB issued an order denying the petition for review on September 30, 2020. The denial was based on the EAB's determination that the petitioners had failed to demonstrate that review of the permit was warranted on any of the grounds presented in the petition. PNM cannot predict whether there will be further appeals of this matter or whether the outcome of any such appeal will have a material impact on PNM’s financial position, results of operations or cash flows. Effluent Limitation Guidelines On June 7, 2013, EPA published proposed revised wastewater effluent limitation guidelines establishing technology-based wastewater discharge limitations for fossil fuel-fired electric power plants. EPA signed the final Steam Electric Effluent Limitation Guidelines rule on September 30, 2015. The final rule, which became effective on January 4, 2016, phased in the new, more stringent requirements in the form of effluent limits for arsenic, mercury, selenium, and nitrogen for wastewater discharged from wet scrubber systems and zero discharge of pollutants in ash transport water that must be incorporated into plants’ NPDES permits. The 2015 rule required each plant to comply between 2018 and 2023 depending on when it needs a new or revised NPDES permit. The Steam Electric Effluent Limitation Guidelines rule was challenged in the U.S. Court of Appeals for the Fifth Circuit by numerous parties. On April 12, 2017, EPA signed a notice indicating its intent to reconsider portions of the rule, and on August 22, 2017, the Fifth Circuit issued an order severing the issues under reconsideration and holding the case in abeyance as to those issues. However, the court allowed challenges to other portions of the rule to proceed. On April 12, 2019, the Fifth Circuit granted those challenges

Regulatory and Rate Matters

Regulatory and Rate Matters	3 Months Ended
	Mar. 31, 2021
Regulated Operations [Abstract]
Regulatory and Rate Matters	Regulatory and Rate Matters The Company is involved in various regulatory matters, some of which contain contingencies that are subject to the same uncertainties as those described in Note 11. Additional information concerning regulatory and rate matters is contained in Note 17 of the Notes to Consolidated Financial Statements in the 2020 Annual Reports on Form 10-K. PNM Renewable Portfolio Standard The REA provides for streamlined proceedings for approval of utilities’ renewable energy procurement plans, assures that utilities recover costs incurred consistent with approved procurement plans, and requires the NMPRC to establish a RCT for the procurement of renewable resources to prevent excessive costs being added to rates. The ETA sets a RCT of $60 per MWh using an average annual levelized resource cost basis. PNM makes renewable procurements consistent with the NMPRC approved plans and recovers certain renewable procurement costs from customers through a rate rider. See Renewable Energy Rider below. Included in PNM’s approved procurement plans are the following renewable energy resources: • 158 MW of PNM-owned solar-PV facilities • A PPA through 2044 for the output of New Mexico Wind, having a current aggregate capacity of 200 MW, and a PPA through 2035 for the output of Red Mesa Wind, having an aggregate capacity of 102 MW • A PPA through 2040 for 140 MW of output from La Joya Wind II • A PPA through 2042 for the output of the Lightning Dock Geothermal facility with a current capacity of 11 MW • Solar distributed generation, aggregating 169.5 MW at March 31, 2021, owned by customers or third parties from whom PNM purchases any net excess output and RECs Renewable Energy Rider The NMPRC has authorized PNM to recover certain renewable procurement costs through a rate rider billed on a per KWh basis. In its 2020 renewable energy procurement plan, which became effective on January 1, 2021, PNM proposed to collect $67.8 million for the year. The NMPRC approved recovery of $65.5 million through the rider, reflecting the rejection of PNM's request to recover the $2.3 million Sky Blue regulatory asset in 2021. PNM recorded revenues from the rider of $15.9 million in the three months ended March 31, 2021, and $15.1 million in the three months ended March 31, 2020. Under the renewable rider, if PNM’s earned rate of return on jurisdictional equity in a calendar year, adjusted for items not representative of normal operations, exceeds the NMPRC-approved rate by 0.5%, PNM is required to refund the excess to customers during May through December of the following year. PNM did not exceed such limitation in 2020. Energy Efficiency and Load Management Program Costs and Incentives/Disincentives The New Mexico Efficient Use of Energy Act (“EUEA”) requires public utilities to achieve specified levels of energy savings and to obtain NMPRC approval to implement energy efficiency and load management programs. The EUEA requires the NMPRC to remove utility disincentives to implementing energy efficiency and load management programs and to provide incentives for such programs. The NMPRC has adopted a rule to implement this act. PNM’s costs to implement approved programs and incentives are recovered through a rate rider. During the 2019 New Mexico legislative session, the EUEA was amended to, among other things, include a decoupling mechanism for disincentives, preclude a reduction to a utility’s ROE based on approval of disincentive or incentive mechanisms, establish energy savings targets for the period 2021 through 2025, and require that annual program funding be 3% to 5% of an electric utility's annual customer bills excluding gross receipt taxes, franchise and right-of-way access fees, provided that a customer's annual cost not exceed seventy-five thousand dollars. In 2019, PNM submitted a filing to address incentives to be earned in 2020. PNM’s proposed incentive mechanism was similar to that approved for 2018 and 2019 with minor modifications to reflect input from interested parties. The proposed incentive mechanism includes a base incentive of 7.1% of program costs, or approximately $1.8 million, based on savings of 59 GWh in 2020 with a sliding scale that provides for additional incentive if savings exceed 68 GWh. No hearings were considered necessary and PNM’s 2020 energy efficiency rider reflecting the 2020 incentive became effective beginning December 30, 2019. On, April 15, 2021 PNM filed its 2020 Energy Efficiency Annual Report which reconciles the actual 2020 profit incentive collections with the profit incentive authorized by the NMPRC resulting in an additional $0.8 million incentive to be collected during the remainder of 2021. The additional incentive was authorized for 2020 because annual energy savings for the year exceeded 87 GWh, and was the maximum level of profit incentive allowed under the approved mechanism. PNM will begin collecting the additional incentive effective May 27, 2021, unless suspended by the NMPRC. On April 15, 2020, PNM filed an application for energy efficiency and load management programs to be offered in 2021, 2022, and 2023. The proposed program portfolio consists of twelve programs with a total annual budget of $31.4 million in 2021, $31.0 million in 2022, and $29.6 million in 2023. The application also sought approval of an annual base incentive of 7.1% of the portfolio budget if PNM were to achieve energy savings of at least 80 GWh in a year. The proposed incentive would increase if PNM is able to achieve savings greater than 80 GWh in a year. The application also proposed an advanced metering infrastructure (“AMI”) pilot program, which included the installation of 5,000 AMI meters at a cost of $2.9 million. PNM proposed the pilot program to comply with an NMPRC order denying PNM’s February 2016 application to replace its existing customer metering equipment with AMI. PNM did not recommend the AMI pilot program due to the limited benefits that are cost-effective under a pilot structure. On September 17, 2020, the Hearing Examiner in the case issued a recommended decision recommending that PNM's proposed energy efficiency and load management program be approved, with the exception of the proposed AMI pilot program. On October 28, 2020, the NMPRC issued an order adopting the recommended decision in its entirety. 2020 Decoupling Petition As discussed above, the legislature amended the EUEA to, among other things, include a decoupling mechanism for disincentives. On May 28, 2020, PNM filed a petition for approval of a rate adjustment mechanism that would decouple the rates of its residential and small power rate classes. Decoupling is a rate design principle that severs the link between the recovery of fixed costs of the utility through volumetric charges. PNM proposed to record the difference between the annual revenue per customer derived from the cost of service approved in the NM 2015 Rate Case and the annual revenue per customer actually recovered from the rate classes beginning on January 1, 2021. If approved, on January 1, 2022, PNM would begin to collect the difference from customers if the revenue per customer from the NM 2015 Rate Case exceeds the actual revenue recovered in 2021, or return the difference to customers if the actual revenue per customer recovered in 2021 exceeds the revenue per customer from the NM 2015 Rate Case. On July 13, 2020, NEE, ABCWUA, the City of Albuquerque, and Bernalillo County filed motions to dismiss the petition on the grounds that approving PNM’s proposed rate adjustment mechanism outside of a general rate case would result in retroactive ratemaking and piecemeal ratemaking. The motions to dismiss also allege that PNM’s proposed rate adjustment mechanism is inconsistent with the EUEA. Responses to the motions to dismiss were filed on August 7, 2020. On September 16, 2020, ABCWUA, Bernalillo County, CCAE, the City of Albuquerque, NEE, NMAG, Staff and WRA filed testimony. CCAE and WRA support PNM's petition, but recommend that the rate adjustment mechanism not take effect until new rates are approved in PNM's next general rate case. The other parties filing testimony oppose PNM's petition. On October 2, 2020, PNM requested an order to vacate the public hearing, scheduled to begin October 13, 2020, and staying the proceeding until the NMPRC decides whether to entertain a petition to issue a declaratory order resolving the issues raised in the motions to dismiss. On October 7, 2020, the Hearing Examiner approved PNM's request to stay the proceeding and vacate the public hearing and required PNM to file a petition for declaratory order by October 30, 2020. On October 30, 2020, PNM filed a petition for declaratory order asking the NMPRC to issue an order finding that full revenue decoupling is authorized by the EUEA. On November 4, 2020, ABCWUA and Bernalillo County jointly filed a competing petition asking the NMPRC to issue a declaratory order on the EUEA’s requirements related to disincentives. On November 24, 2020, the NMAG requested that the NMPRC deny both petitions for declaratory orders and instead address disincentives under the EUEA in a rulemaking. On March 17, 2021, the NMPRC issued an order granting the petitions for declaratory order, commencing a declaratory order proceeding to address the petitions, denying the NMAG’s request to initiate a rulemaking, and appointing a hearing examiner to preside over the declaratory order proceeding. On March 30, 2021, the Hearing Examiner issued a procedural order that requires initial briefs to be filed on June 7, 2021, response briefs to be filed on June 28, 2021, and schedules an oral argument for July 15, 2021. PNM cannot predict the outcome of this matter. Integrated Resource Plans NMPRC rules require that investor owned utilities file an IRP every three years. The IRP is required to cover a 20-year planning period and contain an action plan covering the first four years of that period. 2020 IRP NMPRC rules required PNM to file its 2020 IRP in July 2020. On March 16, 2020, PNM filed a motion to extend the deadline to file its 2020 IRP to six months after the NMPRC issues a final order approving a replacement resource portfolio and closes the docket in the bifurcated SJGS Abandonment Application and replacement resource proceedings. On April 8, 2020, the NMPRC approved PNM's motion to extend the deadline to file its 2020 IRP as requested. On January 29, 2021, PNM filed its 2020 IRP addressing the 20-year planning period from 2020 through 2040. The plan focuses on a carbon-free electricity portfolio by 2040 that would eliminate coal at the end of 2024. This includes replacing the power from San Juan with a mix of approved carbon-free resources and the plan to exit Four Corners at the end of 2024. The plan highlights the need for additional investments in a diverse set of resources, including renewables to supply carbon-free power, energy storage to balance supply and demand, and efficiency and other demand-side resources to mitigate load growth. Abandonment Applications made under the ETA As discussed in Note 11, the ETA sets a statewide standard that requires investor-owned electric utilities to have specified percentages of their electric-generating portfolios be from renewable and zero-carbon generating resources. The ETA also provides for a transition from fossil-fuel generation resources to renewable and other carbon-free resources through certain provisions relating to the abandonment of coal-fired generating facilities. These provisions include the use of energy transition bonds, which are designed to be highly rated bonds that can be issued to finance certain costs of abandoning coal-fired facilities that are retired prior to January 1, 2023, for facilities operated by a “qualifying utility,” or prior to January 1, 2032, for facilities that are not operated by the qualifying utility. SJGS Abandonment Application On July 1, 2019, PNM filed a Consolidated Application for the Abandonment and Replacement of SJGS and Related Securitized Financing Pursuant to the ETA (the “SJGS Abandonment Application”). The SJGS Abandonment Application sought NMPRC approval to retire PNM’s share of SJGS after the existing coal supply and participation agreements end in June 2022, for approval of replacement resources, and for the issuance of approximately $361 million of energy transition bonds (the “Securitized Bonds”). PNM’s request for the issuance of Securitized Bonds included approximately $283 million of forecasted undepreciated investments in SJGS at June 30, 2022, an estimated $28.6 million for plant decommissioning and coal mine reclamation costs, approximately $9.6 million in upfront financing costs, and approximately $20.0 million for job training and severance costs for affected employees. Proceeds from the Securitization Bonds would also be used to fund approximately $19.8 million for economic development in the four corners area. On July 10, 2019, the NMPRC issued an order requiring the SJGS Abandonment Application be considered in two proceedings: one addressing SJGS abandonment and related financing and the other addressing replacement resources. After multiple filings, proceedings, requests for clarification and legal challenges, on January 29, 2020, the NM Supreme Court issued a ruling requiring the NMPRC to apply the ETA to all aspects of PNM’s SJGS Abandonment Application, indicating any previous NMPRC orders inconsistent with the ruling should be vacated, and denying parties’ request for stay. The NM Supreme Court issued a subsequent opinion, on July 23, 2020, more fully explaining the legal rationale for the January 29, 2020 ruling. Hearings on the abandonment and securitized financing proceedings were held in December 2019 and hearings on replacement resources were held in January 2020. On February 21, 2020, the Hearing Examiners issued two recommended decisions recommending approval of PNM’s proposed abandonment of SJGS, subject to approval of replacement resources, and approval of PNM’s proposed financing order to issue Securitized Bonds. The Hearing Examiners recommended that PNM be authorized to abandon SJGS by June 30, 2022, and to record regulatory assets for certain other abandonment costs that are not specifically addressed under the provisions of the ETA to preserve its ability to recover the costs in a future general rate case. The Hearing Examiner recommended that this authority only extend to the deferral of the costs and it not be an approval of any ratemaking treatment. The Hearing Examiners also recommended PNM be authorized to issue Securitized Bonds of up to $361 million and establish a rate rider to collect non-bypassable customer charges for repayment of the bonds and be subject to bi-annual adjustments (the “Energy Transition Charge”). The Hearing Examiners recommended an interim rate rider adjustment upon the start date of the Energy Transition Charge to provide immediate credits to customers for the full value of PNM’s revenue requirement related to SJGS until those reductions are reflected in base rates. In addition, the Hearing Examiners recommended PNM be granted authority to establish regulatory assets to recover costs that PNM will pay prior to the issuance of the Securitized Bonds, including costs associated with the bond issuances as well as for severances, job training, economic development, and workforce training. On April 1, 2020, the NMPRC unanimously approved the Hearing Examiners' recommended decisions regarding the abandonment of SJGS and the related securitized financing under the ETA. On April 10, 2020, CFRE and NEE filed a notice of appeal with the NM Supreme Court of the NMPRC's approval of PNM's request to issue securitized financing under the ETA. The NM Supreme Court granted motions to intervene filed by PNM, WRA, CCAE, and the Sierra Club. On May 8, 2020, CFRE and NEE filed a joint statement of issues with the NM Supreme Court which asserts that the NMPRC improperly applied the ETA and that the ETA violates the New Mexico Constitution. On June 19, 2020, WRA filed a motion to dismiss CFRE and NEE’s constitutional challenges to the ETA on the ground that the New Mexico Constitution provides that only New Mexico district courts have original jurisdiction over the claims. On July 24, 2020, the NM Supreme Court issued an order denying WRA’s motion to dismiss. On August 17, 2020, the appellants filed a Brief in Chief and on October 5, 2020, PNM, WRA, CCAE and Sierra Club filed Answer Briefs. PNM cannot predict the outcome of this matter. PNM evaluated the consequences of the NMPRC's April 1, 2020 orders approving the abandonment of SJGS and the related issuance of Securitized Bonds. This evaluation indicated that it is probable that PNM will be required to fund severances for PNM employees at the facility upon its retirement in 2022 and for PNMR shared services employees providing administrative and other support services to SJGS. In addition, the evaluation indicated that it is probable PNM will be obligated to fund severances and other costs for the WSJ LLC employees and to fund certain state agencies for economic development and workforce training upon the issuance of the Securitized Bonds. As a result, in March 2020, PNMR and PNM recorded obligations of $9.4 million and $8.1 million for estimated severances, $8.9 million for obligations to fund severances and other costs of WSJ LLC employees, and to fund $19.8 million to state agencies for economic development and workforce training upon the issuance of the Securitized Bonds. The total amount recorded for these estimates of $38.1 million and $36.8 million is reflected in other deferred credits and as a corresponding deferred regulatory asset on PNMR's and PNM's Condensed Consolidated Balance Sheets at December 31, 2020. These estimates may be adjusted in future periods as the Company refines its expectations. In addition, as discussed above these costs may be challenged by parties pursuant to the notices of appeal filed with the NM Supreme Court on April 10, 2020. On June 24, 2020, the Hearing Examiners issued a recommended decision on PNM's request for approval of replacement resources that addressed the entire portfolio of replacement resources, which superseded a previous partial recommended decision issued on March 27, 2020. The Hearing Examiners concluded that the ultimate selection of a portfolio of replacement resources involves policy considerations that are the province of the NMPRC and stated that they did not intend to make that decision for the NMPRC. On July 29, 2020, the NMPRC issued an order approving resource selection criteria identified in the ETA and would include PPAs for 650 MW of solar and 300 MW of battery storage. The order also granted in part PNM’s request for an extension of time for PNM to file the application to implement the replacement resource portfolio. PNM has 60 days from the date of the order to file an application in a separate docket seeking approval of the proposed final, executed contracts, for any replacement resources that are not currently in evidence that have been approved by the NMPRC. On September 28, 2020, PNM filed its application for approval of the final executed contracts for the replacement resources. In addition, PNM provided updated costs estimates of $8.1 million for the SJGS replacement resources, based on the NMPRC authorization to create regulatory assets granted in the abandonment order, which it plans to seek recovery of in a future general rate case. On November 13, 2020, the Hearing Examiner issued a recommended decision recommending approval of a 200 MW solar PPA combined with a 100 MW battery storage agreement and the 100 MW solar PPA combined with a 30 MW battery storage agreement. On December 2, 2020, the NMPRC issued an order adopting the recommended decision in its entirety. Additional information concerning the SJGS Abandonment Application is contained in Note 17 of the Notes to Consolidated Financial Statements in the 2020 Annual Reports on Form 10-K. Four Corners Abandonment Application On November 1, 2020, PNM entered into the Four Corners Purchase and Sale Agreement with NTEC, pursuant to which PNM agreed to sell its 13% ownership interest (other than certain transmission assets) in Four Corners to NTEC. The sale is contingent upon NMPRC approval and expected to close by the end of 2024. In connection with the sale, PNM would make payments of $75.0 million to NTEC for relief from its obligations under the coal supply agreement for Four Corners after December 31, 2024. Pursuant to the Four Corners Purchase and Sale Agreement, PNM will retain its current plant decommissioning and coal mine reclamation obligations, subject to the final mine reclamation study and payment at the end of 2024. PNM will have no obligation for reclamation after 2024. PNM made an initial payment to NTEC of $15.0 million in November 2020, subject to refund with interest upon termination of the Four Corners Purchase and Sale Agreement prior to closing. Under the terms of the Four Corners Purchase and Sale Agreement, upon receipt of the NMPRC approval, PNM would make a final payment of $60.0 million. The initial $15.0 million payment was recorded in other current assets on the Consolidated Balance Sheet as of December 31, 2020. On January 8, 2021, PNM filed the Four Corners Abandonment Application, which seeks NMPRC approval to exit PNM’s share of Four Corners as of December 31, 2024, and to issue approximately $300 million of energy transition bonds as provided by the ETA. PNM’s request for the issuance of Securitized Bonds included approximately $272 million of forecasted undepreciated investments in Four Corners at December 31, 2024, an estimated $4.6 million for plant decommissioning costs, estimated $7.3 million in upfront financing costs, and estimated $16.5 million in economic development. PNM intends to submit a separate application for NMPRC approval of a replacement resource portfolio following NMPRC action on this application. This deferral is authorized by the ETA and will provide for adequate time to complete a competitive bid process to develop and finalize a replacement resource portfolio from feasible replacement resources for NMPRC consideration. On January 26, 2021, Sierra Club filed a motion in the Four Corners Abandonment Application requesting that the NMPRC order PNM to file supplemental testimony addressing the prudence of Four Corners investments or alternatively that the NMPRC dismiss the Four Corners Abandonment Application and permit PNM to refile after the prudence issue is resolved. In addition, on January 28, 2021, NEE and CFRE filed a motion requesting that the NMPRC dismiss the application, stating that approval of the abandonment would be contrary to the provision of the REA that prevents the sale of carbon dioxide emitting electricity-generating resources as a means of complying with the RPS, and that the Four Corners Abandonment Application does not demonstrate that the sale of 200 MW to NTEC will not result in a net detriment to public interest. Parties filed positions on the sufficiency of PNM’s application on February 11, 2021. On February 18, 2021, PNM filed a consolidated response to the motions and the positions on the sufficiency of the application which defended the legal sufficiency of PNM’s application and addressed potential amendments to the application and testimonies. On February 26, 2021, the Hearing Examiner issued an order on the sufficiency of the Four Corners Application finding that the application was deficient on its face and fails to adequately support whether or not the sale and transfer of PNM’s interest in Four Corners to NTEC is in the public interest. However, given the NMPRC’s preference to address Four Corners issues in the case, as well as PNM’s concession on filing an amended application, the Hearing Examiner did not recommend that the case be dismissed. The order requires PNM to file an amended application by March 15, 2021; establishes that the nine-month period for review of the amended application shall start on the date of PNM’s filing of the amended application and run through December 15, 2021; requires PNM to file supplemental testimony addressing the prudence of its investment in Four Corners; requires PNM to more explicitly address the statutory standards for approval of the proposed transfer to NTEC; and requires PNM to file a motion to withdraw the January 8, 2021 Four Corners Application. On March 15, 2021, PNM filed an amended application and supplemental testimony for the approval of the abandonment and transfer of Four Corners and issuance of a financing order pursuant to the ETA and a motion to withdraw the January 8, 2021 Four Corners Application. The amended application and supplemental testimony provided additional information to support PNM's request to abandon its interest in Four Corners and transfer that interest to NTEC, and also provided additional detail explaining how the proposed sale and abandonment provides a net public benefit. On March 19, 2021, the Hearing Examiner issued a procedural order requiring Staff and intervenors to file testimony on or before July 12, 2021, requiring any rebuttal testimony be filed on or before August 2, 2021, and scheduling a hearing to begin on August 31, 2021. The procedural order also requires that if a settlement is reached, any stipulation be filed no later than July 12, 2021. On October 30, 2020, NEE filed a formal complaint with the NMPRC seeking an investigation into the reasonableness and lawfulness of PNM’s continued reliance on “climate-altering and uneconomic coal” at Four Corners. NEE explained that they withdrew their Supreme Court appeal of the NM 2016 Rate Case under the notion that PNM would be filing a rate case in 2019 and they would be able to challenge the Four Corners expenditures in that case. NEE explained that because PNM has delayed its rate case several times, Four Corners has remained “imprudently” in rates. NEE asked that PNM be required to demonstrate that PNM’s investment in Four Corners was prudent. NEE stated if the NMPRC deems PNM’s investment as imprudent, ratepayers will be held harmless and all costs including carrying charges, effective October 30, 2020, and going forward, be denied. On February 10, 2021, the NMPRC denied NEE’s complaint and stated that issues related to Four Corners prudence should be addressed in the Four Corners Abandonment Application. On February 22, 2021, NEE filed a Motion for Reconsideration of the NMPRC’s February 10, 2021 order, which was denied on March 10, 2021. On April 9, 2021, NEE filed a Notice of Appeal with the NM Supreme Court regarding their formal complaint on Four Corners. PNM cannot predict the outcome of this matter. The financial impact of an early exit of Four Corners and the NMPRC approval process are influenced by many factors outside of PNM’s control, including the overall political and economic conditions of New Mexico. See additional discussion of the ETA in Note 11. PNM cannot predict the outcome of these matters. PVNGS Leased Interest Abandonment Application On April 2, 2021, PNM filed an application with the NMPRC requesting approval for the decertification and abandonment of 114 MW of leased PVNGS capacity, sale and transfer of related assets, and approval to procure new resources ("PVNGS Leased Interest Abandonment Application"). As discussed in Note 13, PNM currently controls leased capacity in PVNGS Unit 1 and Unit 2 under five separate leases ("Leased Interest") that were approved and certificated by the predecessor agency to the NMPRC in the 1980s. Four of the five leases for 104 MW of Leased Interest terminate on January 15, 2023, while the remaining lease for 10 MW of Leased Interest terminates on January 15, 2024. Associated with the Leased Interest are certain PNM-owned assets and nuclear fuel that are necessary for the ongoing operation and maintenance of the Leased Interest and integration of the Leased Interest generation to the transmission network. PNM has determined that there will be net benefits to its customers to return the Leased Interest to the lessors in conformity with the leases, sell and transfer the related PNM-owned assets, and to replace these Leased Interest with new resources. In the application PNM is requesting NMPRC authorization to decertify and abandon its Leased Interest and to create regulatory assets for the associated remaining undepreciated investments with consideration of cost recovery of the undepreciated investments in a future rate case. PNM is also seeking NMPRC approval to sell and transfer the PNM-owned assets and nuclear fuel supply associated with the Leased Interest to SRP, which will be acquiring the Leased Interest from the lessors upon termination of the existing leases. In addition, PNM is seeking NMPRC approval for a 150 MW solar PPA combined with a 40 MW battery storage agreement, and a stand-alone 100 MW battery storage agreement to replace the Leased Interest. To ensure system reliability and load needs are met in 2023, when a majority of the leases expire, PNM is also requesting NMPRC approval for a 300 MW solar PPA combined with a 150 MW battery storage agreement. PNM's application sought a six-month regulatory time frame. On April 21, 2021, the NMPRC issued an order assigning a hearing examiner and stated PNM's request to abandon the Leased Interest does not have any statutory or rule time limitation and the six-month limit in which the NMPRC must issue an order regarding the request for approvals of the solar PPAs and battery storage agreements does not begin until after the NMPRC acts on the abandonment request. In addition to approval by the NMPRC, PNM and SRP require NRC approval for the transfer of the associated possessory licenses at the end of the term of each of the respective leases. PNM cannot predict the outcome of this matter. Facebook, Inc. Data Center Project PNM has a special service contract to provide service to Facebook, Inc. for a data center being constructed in PNM’s service area. Facebook’s service requirements include the acquisition by PNM of a sufficient amount of new renewable energy resources and RECs to match the energy and capacity requirements of the data center. The cost of renewable energy procured is passed through to Facebook under a rate rider. A special service rate is applied to Facebook’s energy consumption in those hours of the month when their consumption exceeds the energy production from the renewable resources. As of March 31, 2021, PNM is procuring energy from 130 MW of solar-PV capacity from NMRD, a 50% equity method investee of PNMR Development. See additional discussion of NMRD in Note 16. PNM has NMPRC approval for several PPAs to purchase renewable energy and RECs to supply renewable energy to the data center. Details related to these PPAs can be found in Note 17 of the Notes to Consolidated Financial Statements in the 2020 Annual Reports on Form 10-K. On February 8, 2021, PNM filed an application with the NMPRC for approval to service the data center for an additional 190 MW of solar PPA combined with 100 MW of battery storage and a 50 MW solar PPA expected to be operational in 2023. In its application, PNM filed a Motion for Expedited Consideration seeking an expedited schedule for this proceeding that would provide a Final Order by June 1, 2021, in order to facilitate timely completion of the renewable resources to meet the expected completion date of the data center expansion. On February 17, 2021, the NMPRC approved an order with a schedule targeting a final order by June 1, 2021. On April 14, 2021, Staff filed testimony recommending that the NMPRC either extend the targeted date for issuance of a final order to provide more time to review PNM’s application or, in the alternative, issue an order approving the two proposed PPAs and denying the 100 MW of battery storage. PNM filed rebuttal to Staff’s testimony on April 21, 2021. On April 28, 2021, the NMPRC issued an order finding that it requires additional time to review and that a hearing will be held with a hearing examiner presiding. The order sets a procedural schedule to endeavor to provide a Final Order by the end of June 2021. COVID-19 Regulatory Matters In March 2020, PNM and other utilities voluntarily implemented a temporary suspension of disconnections and late payment fees for non-payment of utility bills in response to the impacts of the novel coronavirus global pandemic (“COVID-19”). On March 18, 2020, the NMPRC conducted an emergency open meeting for the purpose of adopting emergen

Lease Commitments

Lease Commitments	3 Months Ended
	Mar. 31, 2021
Leases [Abstract]
Lease Commitments	Lease Commitments The Company leases office buildings, vehicles, and other equipment. In addition, PNM leases interests in PVNGS Units 1 and 2 and certain rights-of-way agreements are classified as leases. All of the Company's leases with terms in excess of one year are recorded on the balance sheet by recording a present value lease liability and a corresponding right-of-use asset. Operating lease expense is recognized within operating expenses according to the use of the asset on a straight-line basis. Financing lease costs, which are comprised primarily of fleet and office equipment leases commencing after January 1, 2019, are recognized by amortizing the right-of-use asset on a straight-line basis and by recording interest expense on the lease liability. Financing lease right-of-use assets amortization is reflected in depreciation and amortization and interest on financing lease liabilities is reflected as interest charges on the Company’s Condensed Consolidated Statements of Earnings. See additional discussion of the Company's leasing activities in Note 8 of the Notes to Consolidated Financial Statements in the 2020 Annual Reports on Form 10-K. PVNGS PNM leases interests in Units 1 and 2 of PVNGS. The PVNGS leases were entered into in 1985 and 1986 and initially were scheduled to expire on January 15, 2015 for the four Unit 1 leases and January 15, 2016 for the four Unit 2 leases. Following procedures set forth in the PVNGS leases, PNM notified four of the lessors under the Unit 1 leases and one lessor under the Unit 2 lease that it would elect to renew those leases on the expiration date of the original leases. The four Unit 1 leases now expire on January 15, 2023 and the one Unit 2 lease now expires on January 15, 2024. The annual lease payments during the renewal periods aggregate $16.5 million for PVNGS Unit 1 and $1.6 million for Unit 2. The terms of each of the extended leases do not provide for additional renewal options beyond their currently scheduled expiration dates. PNM had the option to purchase the assets underlying each of the extended leases at their fair market value or to return the lease interests to the lessors on the expiration dates. On June 11, 2020, PNM provided notice to the lessors and the NMPRC of its intent to return the assets underlying both the PVNGS Unit 1 and Unit 2 leases upon their expiration in January 2023 and 2024. Although PNM elected to return the assets underlying the extended leases, PNM retains certain obligations related to PVNGS, including costs to decommission the facility. PNM is depreciating its capital improvements related to the extended leases using NMPRC approved rates through the end of the NRC license period for each unit, which expire in June 2045 for Unit 1 and in June 2046 for Unit 2. On April 5, 2021, PNM and SRP entered into an Asset Purchase and Sale Agreement, pursuant to which PNM agreed to sell to SRP certain PNM-owned assets and nuclear fuel necessary to the ongoing operation and maintenance of leased capacity in PVNGS Unit 1 and Unit 2, which SRP has agreed to acquire from the lessors upon termination of the existing leases. The proposed transaction between PNM and SRP is subject to receipt by PNM of approval by the NMPRC and PNM and SRP require NRC approval for the transfer of the associated possessory licenses at the end of the term of each of the respective leases. If the proposed transaction is not consummated, PNM may be required to retain all or a portion of its currently leased capacity in PVNGS or be exposed to other claims for damages by the lessors. PNM will seek to recover its undepreciated investments, as well as any other obligations related to PVNGS from NM retail customers. See PVNGS Leased Interest Abandonment Application discussion in Note 12. PNM is exposed to loss under the PVNGS lease arrangements upon the occurrence of certain events that PNM does not consider reasonably likely to occur. Under certain circumstances (for example, the NRC issuing specified violation orders with respect to PVNGS or the occurrence of specified nuclear events), PNM would be required to make specified payments to the lessors and take title to the Leased Interests. If such an event had occurred as of March 31, 2021, amounts due to the lessors under the circumstances described above would be up to $146.5 million, payable on July 15, 2021 in addition to the scheduled lease payments due on that date. Land Easements and Rights-of-Ways Many of PNM’s electric transmission and distribution facilities are located on lands that require the grant of rights-of-way from governmental entities, Native American tribes, or private parties. PNM has completed several renewals of rights-of-way, the largest of which is a renewal with the Navajo Nation. PNM is obligated to pay the Navajo Nation annual payments of $6.0 million, subject to adjustment each year based on the Consumer Price Index, through 2029. PNM’s April 2021 payment for the amount due under the Navajo Nation right-of-way lease was $7.3 million, which included amounts due under the Consumer Price Index adjustment. Changes in the Consumer Price Index subsequent to January 1, 2019 are considered variable lease payments. PNM has other prepaid rights-of-way agreements that are not accounted for as leases or recognized as a component of plant in service. PNM reflects the unamortized balance of these prepayments in other deferred charges on the Condensed Consolidated Balance Sheets and recognizes amortization expense associated with these agreements in the Condensed Consolidated Statement of Earnings over their term. As of March 31, 2021 and December 31, 2020, the unamortized balance of these rights-of-ways was $55.1 million and $55.8 million. PNM recognized amortization expense associated with these agreements of $1.0 million and $0.9 million in the three ended March 31, 2021 and 2020. Fleet Vehicles and Equipment Fleet vehicle and equipment leases commencing on or after January 1, 2019 are classified as financing leases. Fleet vehicle and equipment leases existing as of December 31, 2018 are classified as operating leases. The Company’s fleet vehicle and equipment lease agreements include non-lease components for insignificant administrative and other costs that are billed over the life of the agreement. At March 31, 2021, residual value guarantees on fleet vehicle and equipment leases are $0.9 million, $1.4 million, and $2.3 million for PNM, TNMP, and PNMR Consolidated. Information related to the Company’s operating leases recorded on the Condensed Consolidated Balance Sheets is presented below: March 31, 2021 December 31, 2020 PNM TNMP PNMR Consolidated PNM TNMP PNMR Consolidated (In thousands) Operating leases: Operating lease assets, net of amortization $ 91,652 $ 6,937 $ 99,017 $ 97,461 $ 7,206 $ 105,133 Current portion of operating lease liabilities 25,868 2,185 28,160 25,130 2,193 27,460 Long-term portion of operating lease liabilities 66,657 4,515 71,492 75,941 4,779 81,065 As discussed above, the Company classifies its fleet vehicle and equipment leases and its office equipment leases commencing on or after January 1, 2019 as financing leases. Information related to the Company’s financing leases recorded on the Condensed Consolidated Balance Sheets is presented below: March 31, 2021 December 31, 2020 PNM TNMP PNMR Consolidated PNM TNMP PNMR Consolidated (In thousands) Financing leases: Non-utility property $ 12,140 $ 13,535 $ 25,997 $ 11,453 $ 13,299 $ 25,055 Accumulated depreciation (2,575) (2,833) (5,528) (2,044) (2,241) (4,383) Non-utility property, net 9,565 10,702 20,469 9,409 11,058 20,672 Other current liabilities 2,119 2,436 4,641 1,993 2,397 4,470 Other deferred credits 7,225 8,272 15,616 7,176 8,669 15,972 Information concerning the weighted average remaining lease terms and the weighted average discount rates used to determine the Company’s lease liabilities as of March 31, 2021 is presented below: PNM TNMP PNMR Consolidated Weighted average remaining lease term (years): Operating leases 6.07 3.41 5.89 Financing leases 4.70 4.69 4.67 Weighted average discount rate: Operating leases 3.96 % 3.94 % 3.96 % Financing leases 2.71 % 2.81 % 2.76 % Information for the components of lease expense is as follows: Three Months Ended March 31, 2021 PNM TNMP PNMR Consolidated (In thousands) Operating lease cost: $ 6,735 $ 653 $ 7,429 Amounts capitalized (226) (559) (785) Total operating lease expense $ 6,509 $ 94 $ 6,644 Financing lease cost: Amortization of right-of-use assets 532 613 1,167 Interest on lease liabilities 62 76 139 Amounts capitalized (368) (625) (993) Total financing lease expense 226 64 313 Variable lease expense 63 — 63 Short-term lease expense 124 2 132 Total lease expense for the period $ 6,922 $ 160 $ 7,152 Three Months Ended March 31, 2020 PNM TNMP PNMR Consolidated (In thousands) Operating lease cost: $ 6,893 $ 774 $ 7,735 Amounts capitalized (291) (634) (925) Total operating lease expense $ 6,602 $ 140 $ 6,810 Financing lease cost: Amortization of right-of-use assets 247 289 553 Interest on lease liabilities 45 56 103 Amounts capitalized (175) (283) (458) Total financing lease expense 117 62 198 Variable lease expense 32 — 32 Short-term lease expense 85 1 86 Total lease expense for the period $ 6,836 $ 203 $ 7,126 Supplemental cash flow information related to the Company’s leases is as follows: Three Months Ended Three Months Ended March 31, 2021 March 31, 2020 PNM TNMP PNMR Consolidated PNM TNMP PNMR Consolidated (In thousands) Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 9,246 $ 97 $ 9,401 $ 9,351 $ 166 $ 9,658 Operating cash flows from financing leases 21 8 30 16 9 27 Finance cash flows from financing leases 186 71 278 80 51 147 Non-cash information related to right-of-use assets obtained in exchange for lease obligations: Operating leases $ — $ 317 $ 317 $ — $ — $ — Financing leases 758 387 1,164 1,463 2,802 4,272 Capitalized costs excluded from the operating and financing cash paid for leases above for the three months ended March 31, 2021, are $0.2 million and $0.4 million at PNM, $0.6 million and $0.6 million at TNMP, and $0.8 million and $1.0 million at PNMR. For the three months ended March 31, 2020, capitalized costs excluded are $0.3 million and $0.2 million at PNM, $0.6 million and $0.3 million at TNMP, and $0.9 million and $0.5 million at PNMR. These capitalized costs are reflected as investing activities on the Company’s Condensed Consolidated Statements of Cash Flows for the three months ended March 31, 2021 and 2020. Future expected lease payments are shown below: As of March 31, 2021 PNM TNMP PNMR Consolidated Financing Operating Financing Operating Financing Operating (In thousands) Remainder of 2021 $ 1,760 $ 17,099 $ 2,032 $ 1,831 $ 3,858 $ 19,025 2022 2,296 26,544 2,613 2,039 4,995 28,653 2023 2,229 17,477 2,431 1,548 4,710 19,063 2024 1,565 7,915 1,956 945 3,529 8,897 2025 935 6,919 1,233 763 2,168 7,721 Later years 1,156 27,521 1,153 76 2,308 27,815 Total minimum lease payments 9,941 103,475 11,418 7,202 21,568 111,174 Less: Imputed interest 597 10,950 710 502 1,311 11,522 Lease liabilities as of March 31, 2021 $ 9,344 $ 92,525 $ 10,708 $ 6,700 $ 20,257 $ 99,652
Lease Commitments	Lease Commitments The Company leases office buildings, vehicles, and other equipment. In addition, PNM leases interests in PVNGS Units 1 and 2 and certain rights-of-way agreements are classified as leases. All of the Company's leases with terms in excess of one year are recorded on the balance sheet by recording a present value lease liability and a corresponding right-of-use asset. Operating lease expense is recognized within operating expenses according to the use of the asset on a straight-line basis. Financing lease costs, which are comprised primarily of fleet and office equipment leases commencing after January 1, 2019, are recognized by amortizing the right-of-use asset on a straight-line basis and by recording interest expense on the lease liability. Financing lease right-of-use assets amortization is reflected in depreciation and amortization and interest on financing lease liabilities is reflected as interest charges on the Company’s Condensed Consolidated Statements of Earnings. See additional discussion of the Company's leasing activities in Note 8 of the Notes to Consolidated Financial Statements in the 2020 Annual Reports on Form 10-K. PVNGS PNM leases interests in Units 1 and 2 of PVNGS. The PVNGS leases were entered into in 1985 and 1986 and initially were scheduled to expire on January 15, 2015 for the four Unit 1 leases and January 15, 2016 for the four Unit 2 leases. Following procedures set forth in the PVNGS leases, PNM notified four of the lessors under the Unit 1 leases and one lessor under the Unit 2 lease that it would elect to renew those leases on the expiration date of the original leases. The four Unit 1 leases now expire on January 15, 2023 and the one Unit 2 lease now expires on January 15, 2024. The annual lease payments during the renewal periods aggregate $16.5 million for PVNGS Unit 1 and $1.6 million for Unit 2. The terms of each of the extended leases do not provide for additional renewal options beyond their currently scheduled expiration dates. PNM had the option to purchase the assets underlying each of the extended leases at their fair market value or to return the lease interests to the lessors on the expiration dates. On June 11, 2020, PNM provided notice to the lessors and the NMPRC of its intent to return the assets underlying both the PVNGS Unit 1 and Unit 2 leases upon their expiration in January 2023 and 2024. Although PNM elected to return the assets underlying the extended leases, PNM retains certain obligations related to PVNGS, including costs to decommission the facility. PNM is depreciating its capital improvements related to the extended leases using NMPRC approved rates through the end of the NRC license period for each unit, which expire in June 2045 for Unit 1 and in June 2046 for Unit 2. On April 5, 2021, PNM and SRP entered into an Asset Purchase and Sale Agreement, pursuant to which PNM agreed to sell to SRP certain PNM-owned assets and nuclear fuel necessary to the ongoing operation and maintenance of leased capacity in PVNGS Unit 1 and Unit 2, which SRP has agreed to acquire from the lessors upon termination of the existing leases. The proposed transaction between PNM and SRP is subject to receipt by PNM of approval by the NMPRC and PNM and SRP require NRC approval for the transfer of the associated possessory licenses at the end of the term of each of the respective leases. If the proposed transaction is not consummated, PNM may be required to retain all or a portion of its currently leased capacity in PVNGS or be exposed to other claims for damages by the lessors. PNM will seek to recover its undepreciated investments, as well as any other obligations related to PVNGS from NM retail customers. See PVNGS Leased Interest Abandonment Application discussion in Note 12. PNM is exposed to loss under the PVNGS lease arrangements upon the occurrence of certain events that PNM does not consider reasonably likely to occur. Under certain circumstances (for example, the NRC issuing specified violation orders with respect to PVNGS or the occurrence of specified nuclear events), PNM would be required to make specified payments to the lessors and take title to the Leased Interests. If such an event had occurred as of March 31, 2021, amounts due to the lessors under the circumstances described above would be up to $146.5 million, payable on July 15, 2021 in addition to the scheduled lease payments due on that date. Land Easements and Rights-of-Ways Many of PNM’s electric transmission and distribution facilities are located on lands that require the grant of rights-of-way from governmental entities, Native American tribes, or private parties. PNM has completed several renewals of rights-of-way, the largest of which is a renewal with the Navajo Nation. PNM is obligated to pay the Navajo Nation annual payments of $6.0 million, subject to adjustment each year based on the Consumer Price Index, through 2029. PNM’s April 2021 payment for the amount due under the Navajo Nation right-of-way lease was $7.3 million, which included amounts due under the Consumer Price Index adjustment. Changes in the Consumer Price Index subsequent to January 1, 2019 are considered variable lease payments. PNM has other prepaid rights-of-way agreements that are not accounted for as leases or recognized as a component of plant in service. PNM reflects the unamortized balance of these prepayments in other deferred charges on the Condensed Consolidated Balance Sheets and recognizes amortization expense associated with these agreements in the Condensed Consolidated Statement of Earnings over their term. As of March 31, 2021 and December 31, 2020, the unamortized balance of these rights-of-ways was $55.1 million and $55.8 million. PNM recognized amortization expense associated with these agreements of $1.0 million and $0.9 million in the three ended March 31, 2021 and 2020. Fleet Vehicles and Equipment Fleet vehicle and equipment leases commencing on or after January 1, 2019 are classified as financing leases. Fleet vehicle and equipment leases existing as of December 31, 2018 are classified as operating leases. The Company’s fleet vehicle and equipment lease agreements include non-lease components for insignificant administrative and other costs that are billed over the life of the agreement. At March 31, 2021, residual value guarantees on fleet vehicle and equipment leases are $0.9 million, $1.4 million, and $2.3 million for PNM, TNMP, and PNMR Consolidated. Information related to the Company’s operating leases recorded on the Condensed Consolidated Balance Sheets is presented below: March 31, 2021 December 31, 2020 PNM TNMP PNMR Consolidated PNM TNMP PNMR Consolidated (In thousands) Operating leases: Operating lease assets, net of amortization $ 91,652 $ 6,937 $ 99,017 $ 97,461 $ 7,206 $ 105,133 Current portion of operating lease liabilities 25,868 2,185 28,160 25,130 2,193 27,460 Long-term portion of operating lease liabilities 66,657 4,515 71,492 75,941 4,779 81,065 As discussed above, the Company classifies its fleet vehicle and equipment leases and its office equipment leases commencing on or after January 1, 2019 as financing leases. Information related to the Company’s financing leases recorded on the Condensed Consolidated Balance Sheets is presented below: March 31, 2021 December 31, 2020 PNM TNMP PNMR Consolidated PNM TNMP PNMR Consolidated (In thousands) Financing leases: Non-utility property $ 12,140 $ 13,535 $ 25,997 $ 11,453 $ 13,299 $ 25,055 Accumulated depreciation (2,575) (2,833) (5,528) (2,044) (2,241) (4,383) Non-utility property, net 9,565 10,702 20,469 9,409 11,058 20,672 Other current liabilities 2,119 2,436 4,641 1,993 2,397 4,470 Other deferred credits 7,225 8,272 15,616 7,176 8,669 15,972 Information concerning the weighted average remaining lease terms and the weighted average discount rates used to determine the Company’s lease liabilities as of March 31, 2021 is presented below: PNM TNMP PNMR Consolidated Weighted average remaining lease term (years): Operating leases 6.07 3.41 5.89 Financing leases 4.70 4.69 4.67 Weighted average discount rate: Operating leases 3.96 % 3.94 % 3.96 % Financing leases 2.71 % 2.81 % 2.76 % Information for the components of lease expense is as follows: Three Months Ended March 31, 2021 PNM TNMP PNMR Consolidated (In thousands) Operating lease cost: $ 6,735 $ 653 $ 7,429 Amounts capitalized (226) (559) (785) Total operating lease expense $ 6,509 $ 94 $ 6,644 Financing lease cost: Amortization of right-of-use assets 532 613 1,167 Interest on lease liabilities 62 76 139 Amounts capitalized (368) (625) (993) Total financing lease expense 226 64 313 Variable lease expense 63 — 63 Short-term lease expense 124 2 132 Total lease expense for the period $ 6,922 $ 160 $ 7,152 Three Months Ended March 31, 2020 PNM TNMP PNMR Consolidated (In thousands) Operating lease cost: $ 6,893 $ 774 $ 7,735 Amounts capitalized (291) (634) (925) Total operating lease expense $ 6,602 $ 140 $ 6,810 Financing lease cost: Amortization of right-of-use assets 247 289 553 Interest on lease liabilities 45 56 103 Amounts capitalized (175) (283) (458) Total financing lease expense 117 62 198 Variable lease expense 32 — 32 Short-term lease expense 85 1 86 Total lease expense for the period $ 6,836 $ 203 $ 7,126 Supplemental cash flow information related to the Company’s leases is as follows: Three Months Ended Three Months Ended March 31, 2021 March 31, 2020 PNM TNMP PNMR Consolidated PNM TNMP PNMR Consolidated (In thousands) Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 9,246 $ 97 $ 9,401 $ 9,351 $ 166 $ 9,658 Operating cash flows from financing leases 21 8 30 16 9 27 Finance cash flows from financing leases 186 71 278 80 51 147 Non-cash information related to right-of-use assets obtained in exchange for lease obligations: Operating leases $ — $ 317 $ 317 $ — $ — $ — Financing leases 758 387 1,164 1,463 2,802 4,272 Capitalized costs excluded from the operating and financing cash paid for leases above for the three months ended March 31, 2021, are $0.2 million and $0.4 million at PNM, $0.6 million and $0.6 million at TNMP, and $0.8 million and $1.0 million at PNMR. For the three months ended March 31, 2020, capitalized costs excluded are $0.3 million and $0.2 million at PNM, $0.6 million and $0.3 million at TNMP, and $0.9 million and $0.5 million at PNMR. These capitalized costs are reflected as investing activities on the Company’s Condensed Consolidated Statements of Cash Flows for the three months ended March 31, 2021 and 2020. Future expected lease payments are shown below: As of March 31, 2021 PNM TNMP PNMR Consolidated Financing Operating Financing Operating Financing Operating (In thousands) Remainder of 2021 $ 1,760 $ 17,099 $ 2,032 $ 1,831 $ 3,858 $ 19,025 2022 2,296 26,544 2,613 2,039 4,995 28,653 2023 2,229 17,477 2,431 1,548 4,710 19,063 2024 1,565 7,915 1,956 945 3,529 8,897 2025 935 6,919 1,233 763 2,168 7,721 Later years 1,156 27,521 1,153 76 2,308 27,815 Total minimum lease payments 9,941 103,475 11,418 7,202 21,568 111,174 Less: Imputed interest 597 10,950 710 502 1,311 11,522 Lease liabilities as of March 31, 2021 $ 9,344 $ 92,525 $ 10,708 $ 6,700 $ 20,257 $ 99,652

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes In December 2017, comprehensive changes in United States federal income taxes were enacted through legislation commonly known as the Tax Cuts and Jobs Act (the “Tax Act”). The Tax Act made many significant modifications to the tax laws, including reducing the federal corporate income tax rate from 35% to 21% effective January 1, 2018. The Tax Act also eliminated federal bonus depreciation for utilities, limited interest deductibility for non-utility businesses and limited the deductibility of officer compensation. During 2020, the IRS issued final regulations related to certain officer compensation and, in January 2021, issued final regulations on interest deductibility that provide a 10% “de minimis” exception that allows entities with predominantly regulated activities to fully deduct interest expenses. In addition, in 2019, the IRS issued regulations interpreting Tax Act amendments to depreciation provisions of the IRC that allow the Company to claim a bonus depreciation deduction on certain construction projects placed in service subsequent to the third quarter of 2017. See additional discussion of the impacts of the Tax Act in Note 18 of the Notes to Consolidated Financial Statements in the 2020 Annual Reports on Form 10-K. On March 27, 2020, the Coronavirus Aid, Relief and Economic Security Act (the “CARES Act”) was enacted. Among other things, the CARES Act includes tax provisions that generally loosen restrictions on NOL utilization and business interest deductions, and accelerate refunds of previously generated alternative minimum tax credits. In addition, the CARES Act includes a temporary provision allowing businesses to defer payments to the government for some payroll taxes. In 2020, the Company applied for $5.2 million of accelerated refunds of previously generated alternative minimum tax credits and deferred $7.0 million of payments for certain payroll taxes. The CARES Act provisions related to NOL utilization and business interest deductions are not applicable for the Company. Beginning February 2018, PNM’s NM 2016 Rate Case reflects the reduction in the federal corporate income tax rate, including amortization of excess deferred federal and state income taxes. In accordance with the order in that case, PNM is returning the protected portion of excess deferred federal income taxes to customers over the average remaining life of plant in service as of December 31, 2017, the unprotected portion of excess deferred federal income taxes to customers over a period of approximately twenty-three million, $15.2 million, and $9.3 million in 2021. See additional discussion of PNM’s NM 2016 Rate Case and TNMP’s 2018 Rate Case in Note 17 of the Notes to Consolidated Financial Statements in the 2020 Annual Reports on Form 10-K. The Company makes an estimate of its anticipated effective tax rate for the year as of the end of each quarterly period within its fiscal year. In interim periods, income tax expense is calculated by applying the anticipated annual effective tax rate to year-to-date earnings before income taxes. Certain unusual or infrequently occurring items, including excess tax benefits related to stock awards and taxes on Merger-related costs are excluded from the estimated annual effective tax rate calculation. At March 31, 2021, PNMR, PNM, and TNMP estimated their effective income tax rates for the year ended December 31, 2021 would be 12.91%, 15.40%, and 10.67%. The primary difference between the statutory income tax rates and the effective tax rates is the effect of the reduction in income tax expense resulting from the amortization of excess deferred federal income taxes. During the three months ended March 31, 2021, income tax expense calculated by applying the expected annual effective income tax rate to earnings before income taxes was further reduced by excess tax benefits related to stock awards of $0.7 million for PNMR, of which $0.5 million was allocated to PNM and $0.2 million was allocated to TNMP, and by tax benefits of $1.2 million on Merger-related costs for PNMR.

Related Party Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2021
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions PNMR, PNM, TNMP, and NMRD are considered related parties, as is PNMR Services Company, a wholly-owned subsidiary of PNMR that provides corporate services to PNMR and its subsidiaries in accordance with shared services agreements. These services are billed at cost on a monthly basis to the business units. In addition, PNMR provides construction and operations and maintenance services to NMRD, a 50% owned subsidiary of PNMR Development. PNM purchases renewable energy from certain NMRD-owned facilities at a fixed price per MWh of energy produced. PNM also provides interconnection services to PNMR Development and NMRD. See Note 16 for additional discussion of NMRD. The table below summarizes the nature and amount of related party transactions of PNMR, PNM, TNMP, and NMRD: Three Months Ended March 31, 2021 2020 (In thousands) Services billings: PNMR to PNM $ 26,225 $ 22,123 PNMR to TNMP 10,365 8,727 PNM to TNMP 118 76 TNMP to PNMR 12 35 PNMR to NMRD 55 76 Renewable energy purchases: PNM from NMRD 2,585 1,519 Interconnection billings: PNM to NMRD — 220 PNM to PNMR — — NMRD to PNM 1,276 — Interest billings: PNMR to PNM — — PNM to PNMR 36 81 PNMR to TNMP — 1 Income tax sharing payments: PNMR to PNM — — TNMP to PNMR — —

Equity Method Investment

Equity Method Investment	3 Months Ended
	Mar. 31, 2021
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments	Equity Method InvestmentAs discussed in Note 1 of the Company's 2020 Annual Reports on Form 10-K, PNMR Development and AEP OnSite Partners created NMRD in September 2017 to pursue the acquisition, development, and ownership of renewable energy generation projects, primarily in the state of New Mexico. As of March 31, 2021, NMRD’s renewable energy capacity in operation was 135.1 MW. PNMR Development and AEP OnSite Partners each have a 50% ownership interest in NMRD. The investment in NMRD is accounted for using the equity method of accounting because PNMR’s ownership interest results in significant influence, but not control, over NMRD and its operations. In the three months ended March 31, 2021 and 2020, PNMR Development made cash contributions of zero and $10.0 million to NMRD to be used primarily for its construction activities. In February 2021, NMRD paid PNMR Development a dividend of $3.0 million of which, $2.4 million represents PNMR Development's cumulative equity in earnings of NMRD as of March 31, 2021 and is presented as cash flows from operating activities on the Condensed Consolidated Statement of Cash Flows. The portion of the dividend in excess of PNMR Development's cumulative equity in earnings of NMRD amounting to $0.6 million is presented as cash flows from investing activities. PNMR presents its share of net earnings from NMRD in other income on the Condensed Consolidated Statements of Earnings. Summarized financial information for NMRD is as follows: Results of Operations Three Months Ended March 31, 2021 2020 (In thousands) Operating revenues $ 2,750 $ 1,667 Operating expenses 2,522 1,580 Net earnings $ 228 $ 87 Financial Position March 31, December 31, 2021 2020 (In thousands) Current assets $ 5,005 $ 8,046 Net property, plant, and equipment 170,032 172,585 Non-current assets 2,133 1,900 Total assets 177,170 182,531 Current liabilities 1,249 841 Non-current liabilities 383 380 Owners’ equity $ 175,538 $ 181,310

Merger

Merger	3 Months Ended
	Mar. 31, 2021
Business Combinations [Abstract]
Merger	Merger On October 20, 2020, PNMR, Avangrid, and Merger Sub, entered into the Merger Agreement pursuant to which Merger Sub will merge with and into PNMR, with PNMR surviving the Merger as a wholly-owned subsidiary of Avangrid. Pursuant to the Merger Agreement, each issued and outstanding share of the common stock of PNMR (other than (i) the issued shares of PNMR common stock that are owned by Avangrid, Merger Sub, PNMR or any wholly-owned subsidiary of Avangrid or PNMR, which will be automatically cancelled at the time the Merger is consummated (the "Effective Time") and (ii) shares of PNMR common stock outstanding immediately prior to the Effective Time and held by a holder who has not voted in favor of, or consented in writing to, the Merger who is entitled to, and who has demanded, payment for fair value of such shares) will be converted into the right to receive $50.30 in cash. The proposed Merger has been unanimously approved by the Boards of Directors of PNMR, Avangrid and Merger Sub and approved by PNMR shareholders at the Special Meeting of Shareholders held on February 12, 2021. On January 20, 2021, the FTC notified PNMR and Avangrid that early termination of the waiting period under the HSR Act in connection with the Merger was granted. CFIUS completed its review of the Merger on February 2, 2021, and has concluded that there are no unresolved national security concerns with respect to the Merger. On March 10, 2021 PNMR and Avangrid received FCC approval of the transfer of operating licenses related to the Merger. If the Merger is not completed within 180 days of March 10, 2021, then extension of FCC approval will be required. On April 20, 2021 FERC issued an order authorizing the Merger. Consummation of the Merger remains subject to the satisfaction or waiver of certain customary closing conditions, including, without limitation, the absence of any material adverse effect on PNMR, the receipt of required regulatory approvals (including the PUCT, the NMPRC, and the NRC) and the agreements relating to the divestiture of Four Corners being in full force and effect and all applicable regulatory filings associated therewith being made. The agreement related to the divestiture has been entered into and related filings have been made with the NMPRC. The Merger is currently expected to close in the second half of 2021. On March 30, 2021 TNMP, Merger Sub, Avangrid and all parties to the stipulation (the "Signatories") filed a unanimous stipulation and agreement in its Joint Application for approval of the Merger. The Signatories to the unanimous stipulation agree that a negotiated resolution of this proceeding is in the public interest, will conserve the parties' resources, and will eliminate controversy. The approval of the unanimous stipulation is included on the PUCT's May 6, 2021 open meeting agenda. On April 20, 2021, PNM, PNMR, Merger Sub, Avangrid (the "Joint Applicants"), the NMAG, WRA, the International Brotherhood of Electrical Workers Local 611, Dine, Nava Education Project, the San Juan Citizens Alliance and To Nizhoni Ani, entered into a stipulation and agreement in the Joint Application for approval of Merger pending before the NMPRC. On April 23, 2021, an amended stipulation was filed, which joined CCAE in the stipulation and updated certain stipulated regulatory requirements. On April 25, 2021, the Hearing Examiner in the case issued an order vacating the pre-hearing conference and procedural schedule. The order requires the Joint Applicants to meet with all parties to discuss and negotiate, in good faith, a potential stipulation and establishes a deadline of May 7, 2021 for the Joint Applicants to file a stipulation and a proposed procedural schedule. In connection with the Merger, Iberdrola, S.A., a corporation organized under the laws of the Kingdom of Spain (“Iberdrola”), which owns 81.5% of the outstanding common stock of Avangrid, has provided Avangrid a commitment letter (the "Iberdrola Funding Commitment Letter"), pursuant to which Iberdrola has unilaterally agreed to provide to Avangrid, or arrange the provision to Avangrid of, funds to the extent necessary for Avangrid to consummate the Merger, including the payment of the aggregate Merger consideration. To the extent Avangrid wishes to effect a funding transaction under the Iberdrola Funding Commitment Letter in order to pay the Merger consideration, the specific terms of any such transaction will be negotiated between Iberdrola and Avangrid on an arm's length basis and must be approved by both (i) a majority of the members of the unaffiliated committee of the board of directors of Avangrid, and (ii) the entire board of directors of Avangrid. Under the terms of such commitment letter, Iberdrola has agreed to negotiate with Avangrid the specific terms of any transaction effecting such funding commitment promptly and in good faith, with the objective that such terms shall be commercially reasonable and approved by Avangrid. Avangrid’s and Merger Sub’s obligations under the Merger Agreement are not conditioned upon Avangrid obtaining financing. The Merger Agreement provides for certain customary termination rights including the right of either party to terminate the Merger Agreement if the Merger is not completed on or before January 20, 2022 (subject to a three-month extension by either party if all of the conditions to the closing, other than the conditions related to obtaining regulatory approvals, have been satisfied or waived). The Merger Agreement further provides that, upon termination of the Merger Agreement under certain specified circumstances (including if Avangrid terminates the Merger Agreement due to a change in recommendation of the Board or if PNMR terminates the Merger Agreement to accept a superior proposal (as defined in the Merger Agreement)), PNMR will be required to pay Avangrid a termination fee of $130.0 million. In addition, the Merger Agreement provides that (i) if the Merger Agreement is terminated by either party due to a failure of a regulatory closing condition and such failure is the result of Avangrid’s breach of its regulatory covenants or (ii) Avangrid fails to effect the closing when all closing conditions have been satisfied and it is otherwise obligated to do so under the Merger Agreement, then, in either such case, upon termination of the Merger Agreement, Avangrid will be required to pay PNMR a termination fee of $184.0 million as the sole and exclusive remedy. Upon the termination of the Merger Agreement under certain specified circumstances involving a breach of the Merger Agreement, either PNMR or Avangrid will be required to reimburse the other party’s reasonable and documented out-of-pocket fees and expenses up to $10.0 million (which amount will be credited toward, and offset against, the payment of any applicable termination fee).

Significant Accounting Polici_2

Significant Accounting Policies and Responsibility for Financial Statements (Policies)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Principles of Consolidation	The Condensed Consolidated Financial Statements of each of PNMR, PNM, and TNMP include their accounts and those of subsidiaries in which that entity owns a majority voting interest. PNM also consolidates Valencia. See Note 6. PNM owns undivided interests in several jointly-owned power plants and records its pro-rata share of the assets, liabilities, and expenses for those plants. The agreements for the jointly-owned plants provide that if an owner were to default on its payment obligations, the non-defaulting owners would be responsible for their proportionate share of the obligations of the defaulting owner. In exchange, the non-defaulting owners would be entitled to their proportionate share of the generating capacity of the defaulting owner. There have been no such payment defaults under any of the agreements for the jointly-owned plants.PNMR Services Company expenses, which represent costs that are primarily driven by corporate level activities, are charged to the business segments. These services are billed at cost and are reflected as general and administrative expenses in the business segments. Other significant intercompany transactions between PNMR, PNM, and TNMP include interest and income tax sharing payments, as well as equity transactions, and interconnection billings. See Note 15. All intercompany transactions and balances have been eliminated.

Segment Information (Tables)

Segment Information (Tables)	3 Months Ended
	Mar. 31, 2021
Segment Reporting [Abstract]
Summary of Financial Information by Segment	The following tables present summarized financial information for PNMR by segment. PNM and TNMP each operate in only one segment. Therefore, tabular segment information is not presented for PNM and TNMP. PNMR SEGMENT INFORMATION PNM TNMP Corporate PNMR Consolidated (In thousands) Three Months Ended March 31, 2021 Electric operating revenues $ 271,213 $ 93,494 $ — $ 364,707 Cost of energy 88,886 26,510 — 115,396 Utility margin 182,327 66,984 — 249,311 Other operating expenses 107,328 27,769 1,174 136,271 Depreciation and amortization 41,949 22,190 5,735 69,874 Operating income (loss) 33,050 17,025 (6,909) 43,166 Interest income 3,595 — (36) 3,559 Other income 1,244 1,062 (376) 1,930 Interest charges (12,893) (8,475) (4,516) (25,884) Segment earnings (loss) before income taxes 24,996 9,612 (11,837) 22,771 Income taxes (benefit) 2,834 877 (2,145) 1,566 Segment earnings (loss) 22,162 8,735 (9,692) 21,205 Valencia non-controlling interest (3,494) — — (3,494) Subsidiary preferred stock dividends (132) — — (132) Segment earnings (loss) attributable to PNMR $ 18,536 $ 8,735 $ (9,692) $ 17,579 At March 31, 2021: Total Assets $ 5,561,146 $ 2,163,250 $ 218,913 $ 7,943,309 Goodwill $ 51,632 $ 226,665 $ — $ 278,297 PNM TNMP Corporate PNMR Consolidated (In thousands) Three Months Ended March 31, 2020 Electric operating revenues $ 248,133 $ 85,489 $ — $ 333,622 Cost of energy 74,524 24,186 — 98,710 Utility margin 173,609 61,303 — 234,912 Other operating expenses 98,555 25,122 (5,476) 118,201 Depreciation and amortization 41,449 21,836 5,688 68,973 Operating income (loss) 33,605 14,345 (212) 47,738 Interest income 3,496 — (73) 3,423 Other income (deductions) (34,027) 561 (540) (34,006) Interest charges (17,629) (7,172) (5,633) (30,434) Segment earnings (loss) before income taxes (14,555) 7,734 (6,458) (13,279) Income taxes (benefit) (2,359) 642 (163) (1,880) Segment earnings (loss) (12,196) 7,092 (6,295) (11,399) Valencia non-controlling interest (3,729) — — (3,729) Subsidiary preferred stock dividends (132) — — (132) Segment earnings (loss) attributable to PNMR $ (16,057) $ 7,092 $ (6,295) $ (15,260) At March 31, 2020: Total Assets $ 5,260,528 $ 1,913,270 $ 201,321 $ 7,375,119 Goodwill $ 51,632 $ 226,665 $ — $ 278,297

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Loss) (Tables)	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss)	Information regarding accumulated other comprehensive income (loss) for the three months ended March 31, 2021 and 2020 is as follows: Accumulated Other Comprehensive Income (Loss) PNM Corporate and Other PNMR Consolidated Unrealized Pension Fair Value Total Total (In thousands) Balance at December 31, 2020 $ 20,403 $ (98,914) $ (78,511) $ (672) $ (79,183) Amounts reclassified from AOCI (pre-tax) (3,618) 2,087 (1,531) (624) (2,155) Income tax impact of amounts reclassified 919 (530) 389 158 547 Other OCI changes (pre-tax) (3,326) — (3,326) 1,247 (2,079) Income tax impact of other OCI changes 845 — 845 (317) 528 Net after-tax change (5,180) 1,557 (3,623) 464 (3,159) Balance at March 31, 2021 $ 15,223 $ (97,357) $ (82,134) $ (208) $ (82,342) Balance at December 31, 2019 $ 10,638 $ (109,693) $ (99,055) $ (322) $ (99,377) Amounts reclassified from AOCI (pre-tax) (1,185) 2,075 890 (38) 852 Income tax impact of amounts reclassified 301 (527) (226) 10 (216) Other OCI changes (pre-tax) (4,283) — (4,283) (1,998) (6,281) Income tax impact of other OCI changes 1,088 — 1,088 507 1,595 Net after-tax change (4,079) 1,548 (2,531) (1,519) (4,050) Balance at March 31, 2020 $ 6,559 $ (108,145) $ (101,586) $ (1,841) $ (103,427)

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
Computation of Earnings Per Share	Information regarding the computation of earnings per share is as follows: Three Months Ended March 31, 2021 2020 (In thousands, except per share amounts) Net Earnings (Loss) Attributable to PNMR $ 17,579 $ (15,260) Average Number of Common Shares: Outstanding during period 85,835 79,654 Vested awards of restricted stock 196 217 Average Shares – Basic 86,031 79,871 Dilutive Effect of Common Stock Equivalents: Restricted stock 24 — Average Shares – Diluted 86,055 79,871 Net Earnings (Loss) Per Share of Common Stock: Basic $ 0.20 $ (0.19) Diluted $ 0.20 $ (0.19) (1) No potentially dilutive restricted stock or PNMR common stock under the PNMR 2020 Forward Equity Sale Agreements have been included in the computation of Average Shares – Diluted for the three months ended March 31, 2020 since the effect would be anti-dilutive.

Electric Operating Revenues (Ta

Electric Operating Revenues (Tables)	3 Months Ended
	Mar. 31, 2021
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	A disaggregation of revenues from contracts with customers by the type of customer is presented in the table below. The table also reflects alternative revenue program revenues ("ARP") and other revenues. PNM TNMP PNMR Consolidated Three Months Ended March 31, 2021 (In thousands) Electric Operating Revenues: Contracts with customers: Retail electric revenue Residential $ 114,669 $ 35,094 $ 149,763 Commercial 81,934 29,429 111,363 Industrial 18,900 7,293 26,193 Public authority 4,587 1,482 6,069 Economy energy service 10,581 — 10,581 Transmission 17,503 21,121 38,624 Miscellaneous 3,032 960 3,992 Total revenues from contracts with customers 251,206 95,379 346,585 Alternative revenue programs 976 (1,885) (909) Other electric operating revenues 19,031 — 19,031 Total Electric Operating Revenues $ 271,213 $ 93,494 $ 364,707 Three Months Ended March 31, 2020 Electric Operating Revenues: Contracts with customers: Retail electric revenue Residential $ 102,809 $ 31,898 $ 134,707 Commercial 86,349 28,685 115,034 Industrial 19,466 6,533 25,999 Public authority 4,347 1,423 5,770 Economy energy service 5,253 — 5,253 Transmission 14,167 18,012 32,179 Miscellaneous 3,368 673 4,041 Total revenues from contracts with customers 235,759 87,224 322,983 Alternative revenue programs 2,161 (1,735) 426 Other electric operating revenues 10,213 — 10,213 Total Electric Operating Revenues $ 248,133 $ 85,489 $ 333,622

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	3 Months Ended
	Mar. 31, 2021
Variable Interest Entities [Abstract]
Summarized Financial Information	Summarized financial information for Valencia is as follows: Results of Operations Three Months Ended March 31, 2021 2020 (In thousands) Operating revenues $ 5,127 $ 5,353 Operating expenses 1,633 1,624 Earnings attributable to non-controlling interest $ 3,494 $ 3,729 Financial Position March 31, December 31, 2021 2020 (In thousands) Current assets $ 3,282 $ 3,911 Net property, plant, and equipment 55,035 55,744 Total assets 58,317 59,655 Current liabilities 1,057 646 Owners’ equity – non-controlling interest $ 57,260 $ 59,009

Fair Value of Derivative and _2

Fair Value of Derivative and Other Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2021
Fair Value of Derivative and Other Financial Instruments [Abstract]
Summary of Derivatives	PNM’s commodity derivative instruments that are recorded at fair value, all of which are accounted for as economic hedges and considered Level 2 fair value measurements, are presented in the following line items on the Condensed Consolidated Balance Sheets: Economic Hedges March 31, December 31, (In thousands) Other current assets $ 1,097 $ 1,096 Other deferred charges 183 455 1,280 1,551 Other current liabilities (1,097) (1,096) Other deferred credits (183) (455) (1,280) (1,551) Net $ — $ —
Schedule of Gross Realized Gains and Losses	Gains and losses recognized on the Condensed Consolidated Statements of Earnings related to investment securities in the NDT and reclamation trusts are presented in the following table: Three Months Ended March 31, 2021 2020 (In thousands) Equity securities: Net gains (losses) from equity securities sold $ 2,022 $ (1,315) Net gains (losses) from equity securities still held (3,166) (18,931) Total net gains (losses) on equity securities (1,144) (20,246) Available-for-sale debt securities: Net gains (losses) on debt securities 2,112 (12,603) Net gains (losses) on investment securities $ 968 $ (32,849) The proceeds and gross realized gains and losses on the disposition of securities held in the NDT and coal mine reclamation trusts are shown in the following table. Realized gains and losses are determined by specific identification of costs of securities sold. Gross realized losses shown below exclude the (increase)/decrease in realized impairment losses of $1.1 million and $(12.7) million for the three months ended March 31, 2021 and 2020. Three Months Ended March 31, 2021 2020 (In thousands) Proceeds from sales $ 123,596 $ 149,355 Gross realized gains $ 8,692 $ 5,825 Gross realized (losses) $ (3,443) $ (7,035)
Investments Classified by Contractual Maturity Date	At March 31, 2021, the available-for-sale debt securities held by PNM, had the following final maturities: Fair Value (In thousands) Within 1 year $ 31,510 After 1 year through 5 years 71,643 After 5 years through 10 years 103,946 After 10 years through 15 years 18,105 After 15 years through 20 years 11,804 After 20 years 34,529 $ 271,537
Schedule of Investments	Items recorded at fair value by PNM on the Condensed Consolidated Balance Sheets are presented below by level of the fair value hierarchy along with gross unrealized gains on investments in available-for-sale debt securities: GAAP Fair Value Hierarchy Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Unrealized Gains (In thousands) March 31, 2021 Cash and cash equivalents $ 11,590 $ 11,590 $ — Equity securities: Corporate stocks, common 86,527 86,527 — Corporate stocks, preferred 9,835 3,456 6,379 Mutual funds and other 57,539 57,498 41 Available-for-sale debt securities: U.S. government 58,575 31,193 27,382 $ 388 International government 15,380 — 15,380 1,641 Municipals 47,188 — 47,188 2,080 Corporate and other 150,394 — 150,394 16,334 $ 437,028 $ 190,264 $ 246,764 $ 20,443 December 31, 2020 Cash and cash equivalents $ 6,107 $ 6,107 $ — Equity securities: Corporate stocks, common 85,271 85,271 — Corporate stocks, preferred 9,910 3,608 6,302 Mutual funds and other 58,817 58,762 55 Available-for-sale debt securities: U.S. government 55,839 29,579 26,260 $ 950 International government 16,032 — 16,032 2,537 Municipals 50,139 — 50,139 2,779 Corporate and other 158,000 3 157,997 21,121 $ 440,115 $ 183,330 $ 256,785 $ 27,387
Schedule of Carrying Amount and Fair Value of Items Not Recorded at Fair Value	The carrying amounts and fair values of long-term debt, all of which are considered Level 2 fair value measurements and are not recorded at fair value on the Condensed Consolidated Balance Sheets, are presented below: Carrying Amount Fair Value March 31, 2021 (In thousands) PNMR $ 3,215,692 $ 3,157,858 PNM $ 1,697,195 $ 1,561,816 TNMP $ 853,639 $ 931,042 December 31, 2020 PNMR $ 3,295,150 $ 3,355,761 PNM $ 1,696,620 $ 1,602,547 TNMP $ 853,673 $ 1,006,722

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2021
Share-based Payment Arrangement [Abstract]
Summary of Activity	The following table summarizes the weighted-average assumptions used to determine the awards grant date fair value: Three Months Ended March 31, Restricted Shares and Performance Based Shares 2021 2020 Expected quarterly dividends per share $ 0.3275 $ 0.3075 Risk-free interest rate 0.32 % 0.72 % Market-Based Shares Dividend yield 2.76 % 2.51 % Expected volatility 33.69 % 19.41 % Risk-free interest rate 0.29 % 0.72 % The following table summarizes activity in restricted stock awards, including performance-based and market-based shares for the three months ended March 31, 2021: Restricted Stock Shares Weighted- Outstanding at December 31, 2020 168,061 $ 40.77 Granted 194,075 43.68 Exercised (189,098) 42.26 Forfeited (851) 43.77 Outstanding at March 31, 2021 172,187 $ 42.41 The following table provides additional information concerning restricted stock activity, including performance-based and market-based shares, and stock options: Three Months Ended March 31, Restricted Stock 2021 2020 Weighted-average grant date fair value $ 43.68 $ 36.88 Total fair value of restricted shares that vested (in thousands) $ 8,967 $ 11,269 Stock Options Total intrinsic value of options exercised (in thousands) $ — $ 84

Financing (Tables)

Financing (Tables)	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Schedule of Short-term Debt	Short-term debt outstanding consists of: March 31, December 31, Short-term Debt 2021 2020 (In thousands) PNM: PNM Revolving Credit Facility $ — $ — PNM 2017 New Mexico Credit Facility — 10,000 — 10,000 TNMP Revolving Credit Facility 43,100 — PNMR: PNMR Revolving Credit Facility 114,400 12,000 PNMR Development Revolving Credit Facility 40,000 10,000 $ 197,500 $ 32,000

Pension and Other Postretirem_2

Pension and Other Postretirement Benefit Plans (Tables)	3 Months Ended
	Mar. 31, 2021
Retirement Benefits [Abstract]
Schedule of Net Benefit Costs	The following table presents the components of the PNM Plans’ net periodic benefit cost: Three Months Ended March 31, Pension Plan OPEB Plan Executive Retirement Program 2021 2020 2021 2020 2021 2020 (In thousands) Components of Net Periodic Benefit Cost Service cost $ — $ — $ 6 $ 10 $ — $ — Interest cost 4,036 4,985 477 613 90 122 Expected return on plan assets (7,133) (7,363) (1,042) (1,387) — — Amortization of net loss 4,541 4,465 — 87 100 101 Amortization of prior service cost — (138) — — — — Net Periodic Benefit Cost (Income) $ 1,444 $ 1,949 $ (559) $ (677) $ 190 $ 223 The following table presents the components of the TNMP Plans’ net periodic benefit cost: Three Months Ended March 31, Pension Plan OPEB Plan Executive Retirement Program 2021 2020 2021 2020 2021 2020 (In thousands) Components of Net Periodic Benefit Cost Service cost $ — $ — $ 11 $ 12 $ — $ — Interest cost 435 544 77 93 4 6 Expected return on plan assets (795) (821) (102) (134) — — Amortization of net (gain) loss 312 315 (80) (81) 9 6 Amortization of prior service cost — — — — — — Net Periodic Benefit Cost (Income) $ (48) $ 38 $ (94) $ (110) $ 13 $ 12

Regulatory and Rate Matters (Ta

Regulatory and Rate Matters (Tables)	3 Months Ended
	Mar. 31, 2021
Regulated Operations [Abstract]
Schedule of Rate Increases for Transmission Costs	The following sets forth TNMP’s recent interim transmission cost rate increases: Effective Date Approved Increase in Rate Base Annual Increase in Revenue (In millions) March 27, 2020 59.2 7.8 October 7, 2020 10.8 2.0 March 12, 2021 112.6 14.1

Lease Commitments (Tables)

Lease Commitments (Tables)	3 Months Ended
	Mar. 31, 2021
Leases [Abstract]
Assets and Liabilities, Lessee	Information related to the Company’s operating leases recorded on the Condensed Consolidated Balance Sheets is presented below: March 31, 2021 December 31, 2020 PNM TNMP PNMR Consolidated PNM TNMP PNMR Consolidated (In thousands) Operating leases: Operating lease assets, net of amortization $ 91,652 $ 6,937 $ 99,017 $ 97,461 $ 7,206 $ 105,133 Current portion of operating lease liabilities 25,868 2,185 28,160 25,130 2,193 27,460 Long-term portion of operating lease liabilities 66,657 4,515 71,492 75,941 4,779 81,065 March 31, 2021 December 31, 2020 PNM TNMP PNMR Consolidated PNM TNMP PNMR Consolidated (In thousands) Financing leases: Non-utility property $ 12,140 $ 13,535 $ 25,997 $ 11,453 $ 13,299 $ 25,055 Accumulated depreciation (2,575) (2,833) (5,528) (2,044) (2,241) (4,383) Non-utility property, net 9,565 10,702 20,469 9,409 11,058 20,672 Other current liabilities 2,119 2,436 4,641 1,993 2,397 4,470 Other deferred credits 7,225 8,272 15,616 7,176 8,669 15,972 Information concerning the weighted average remaining lease terms and the weighted average discount rates used to determine the Company’s lease liabilities as of March 31, 2021 is presented below: PNM TNMP PNMR Consolidated Weighted average remaining lease term (years): Operating leases 6.07 3.41 5.89 Financing leases 4.70 4.69 4.67 Weighted average discount rate: Operating leases 3.96 % 3.94 % 3.96 % Financing leases 2.71 % 2.81 % 2.76 %
Lease, Cost	Information for the components of lease expense is as follows: Three Months Ended March 31, 2021 PNM TNMP PNMR Consolidated (In thousands) Operating lease cost: $ 6,735 $ 653 $ 7,429 Amounts capitalized (226) (559) (785) Total operating lease expense $ 6,509 $ 94 $ 6,644 Financing lease cost: Amortization of right-of-use assets 532 613 1,167 Interest on lease liabilities 62 76 139 Amounts capitalized (368) (625) (993) Total financing lease expense 226 64 313 Variable lease expense 63 — 63 Short-term lease expense 124 2 132 Total lease expense for the period $ 6,922 $ 160 $ 7,152 Three Months Ended March 31, 2020 PNM TNMP PNMR Consolidated (In thousands) Operating lease cost: $ 6,893 $ 774 $ 7,735 Amounts capitalized (291) (634) (925) Total operating lease expense $ 6,602 $ 140 $ 6,810 Financing lease cost: Amortization of right-of-use assets 247 289 553 Interest on lease liabilities 45 56 103 Amounts capitalized (175) (283) (458) Total financing lease expense 117 62 198 Variable lease expense 32 — 32 Short-term lease expense 85 1 86 Total lease expense for the period $ 6,836 $ 203 $ 7,126
Schedule of Leases, Supplemental Cash Flows	Supplemental cash flow information related to the Company’s leases is as follows: Three Months Ended Three Months Ended March 31, 2021 March 31, 2020 PNM TNMP PNMR Consolidated PNM TNMP PNMR Consolidated (In thousands) Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 9,246 $ 97 $ 9,401 $ 9,351 $ 166 $ 9,658 Operating cash flows from financing leases 21 8 30 16 9 27 Finance cash flows from financing leases 186 71 278 80 51 147 Non-cash information related to right-of-use assets obtained in exchange for lease obligations: Operating leases $ — $ 317 $ 317 $ — $ — $ — Financing leases 758 387 1,164 1,463 2,802 4,272
Lessee, Operating Lease, Liability, Maturity	Future expected lease payments are shown below: As of March 31, 2021 PNM TNMP PNMR Consolidated Financing Operating Financing Operating Financing Operating (In thousands) Remainder of 2021 $ 1,760 $ 17,099 $ 2,032 $ 1,831 $ 3,858 $ 19,025 2022 2,296 26,544 2,613 2,039 4,995 28,653 2023 2,229 17,477 2,431 1,548 4,710 19,063 2024 1,565 7,915 1,956 945 3,529 8,897 2025 935 6,919 1,233 763 2,168 7,721 Later years 1,156 27,521 1,153 76 2,308 27,815 Total minimum lease payments 9,941 103,475 11,418 7,202 21,568 111,174 Less: Imputed interest 597 10,950 710 502 1,311 11,522 Lease liabilities as of March 31, 2021 $ 9,344 $ 92,525 $ 10,708 $ 6,700 $ 20,257 $ 99,652
Finance Lease, Liability, Maturity	Future expected lease payments are shown below: As of March 31, 2021 PNM TNMP PNMR Consolidated Financing Operating Financing Operating Financing Operating (In thousands) Remainder of 2021 $ 1,760 $ 17,099 $ 2,032 $ 1,831 $ 3,858 $ 19,025 2022 2,296 26,544 2,613 2,039 4,995 28,653 2023 2,229 17,477 2,431 1,548 4,710 19,063 2024 1,565 7,915 1,956 945 3,529 8,897 2025 935 6,919 1,233 763 2,168 7,721 Later years 1,156 27,521 1,153 76 2,308 27,815 Total minimum lease payments 9,941 103,475 11,418 7,202 21,568 111,174 Less: Imputed interest 597 10,950 710 502 1,311 11,522 Lease liabilities as of March 31, 2021 $ 9,344 $ 92,525 $ 10,708 $ 6,700 $ 20,257 $ 99,652

Related Party Transactions (Tab

Related Party Transactions (Tables)	3 Months Ended
	Mar. 31, 2021
Related Party Transactions [Abstract]
Schedule of Related Party Transactions	The table below summarizes the nature and amount of related party transactions of PNMR, PNM, TNMP, and NMRD: Three Months Ended March 31, 2021 2020 (In thousands) Services billings: PNMR to PNM $ 26,225 $ 22,123 PNMR to TNMP 10,365 8,727 PNM to TNMP 118 76 TNMP to PNMR 12 35 PNMR to NMRD 55 76 Renewable energy purchases: PNM from NMRD 2,585 1,519 Interconnection billings: PNM to NMRD — 220 PNM to PNMR — — NMRD to PNM 1,276 — Interest billings: PNMR to PNM — — PNM to PNMR 36 81 PNMR to TNMP — 1 Income tax sharing payments: PNMR to PNM — — TNMP to PNMR — —

Equity Method Investment (Table

Equity Method Investment (Tables)	3 Months Ended
	Mar. 31, 2021
Equity Method Investments and Joint Ventures [Abstract]
Marketable Securities	Summarized financial information for NMRD is as follows: Results of Operations Three Months Ended March 31, 2021 2020 (In thousands) Operating revenues $ 2,750 $ 1,667 Operating expenses 2,522 1,580 Net earnings $ 228 $ 87 Financial Position March 31, December 31, 2021 2020 (In thousands) Current assets $ 5,005 $ 8,046 Net property, plant, and equipment 170,032 172,585 Non-current assets 2,133 1,900 Total assets 177,170 182,531 Current liabilities 1,249 841 Non-current liabilities 383 380 Owners’ equity $ 175,538 $ 181,310

Significant Accounting Polici_3

Significant Accounting Policies and Responsibility for Financial Statements (Details) - USD ($)	1 Months Ended		3 Months Ended
	Mar. 31, 2021	Feb. 29, 2020	Mar. 31, 2021	Mar. 31, 2020
Business Acquisition [Line Items]
Payment defaults under agreements	$ 0		$ 0
Dividends declared per common share (dollars per share)	$ 0.3275	$ 0.3075	$ 0.3275	$ 0.3075
Dividends declared on common stock			$ 28,111,000	$ 24,493,000
PNM
Business Acquisition [Line Items]
Dividends declared on common stock				40,654,000
Texas-New Mexico Power Company
Business Acquisition [Line Items]
Dividends declared on common stock				$ 11,347,000

Segment Information - Summarize

Segment Information - Summarized Financial Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)segment	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)
Segment Reporting Information [Line Items]
Number of operating segments | segment	1
Segment Reporting Information, Profit (Loss) [Abstract]
Electric operating revenues	$ 364,707	$ 333,622
Other operating expenses	136,271	118,201
Depreciation and amortization	69,874	68,973
Operating income	43,166	47,738
Interest income	3,559	3,423
Other income (deductions)	1,930	(34,006)
Interest charges	(25,884)	(30,434)
Earnings (Loss) before Income Taxes	22,771	(13,279)
Income taxes (benefit)	1,566	(1,880)
Net Earnings (Loss)	21,205	(11,399)
Valencia non-controlling interest	(3,494)	(3,729)
Subsidiary preferred stock dividends	(132)	(132)
Net Earnings (Loss) Available for PNM Common Stock	17,579	(15,260)
Total Assets	7,943,309	7,375,119	$ 7,939,854
Goodwill	278,297	278,297	$ 278,297
PNM
Segment Reporting Information, Profit (Loss) [Abstract]
Other operating expenses	107,328	98,555
Depreciation and amortization	41,949	41,449
Operating income	33,050	33,605
Interest income	3,595	3,496
Other income (deductions)	1,244	(34,027)
Interest charges	(12,893)	(17,629)
Earnings (Loss) before Income Taxes	24,996	(14,555)
Income taxes (benefit)	2,834	(2,359)
Net Earnings (Loss)	22,162	(12,196)
Valencia non-controlling interest	(3,494)	(3,729)
Subsidiary preferred stock dividends	(132)	(132)
Net Earnings (Loss) Available for PNM Common Stock	18,536	(16,057)
Total Assets	5,561,146	5,260,528
Goodwill	51,632	51,632
TNMP
Segment Reporting Information, Profit (Loss) [Abstract]
Other operating expenses	27,769	25,122
Depreciation and amortization	22,190	21,836
Operating income	17,025	14,345
Interest income	0	0
Other income (deductions)	1,062	561
Interest charges	(8,475)	(7,172)
Earnings (Loss) before Income Taxes	9,612	7,734
Income taxes (benefit)	877	642
Net Earnings (Loss)	8,735	7,092
Valencia non-controlling interest	0	0
Subsidiary preferred stock dividends	0	0
Net Earnings (Loss) Available for PNM Common Stock	8,735	7,092
Total Assets	2,163,250	1,913,270
Goodwill	226,665	226,665
Corporate and Other
Segment Reporting Information, Profit (Loss) [Abstract]
Other operating expenses	1,174	(5,476)
Depreciation and amortization	5,735	5,688
Operating income	(6,909)	(212)
Interest income	(36)	(73)
Other income (deductions)	(376)	(540)
Interest charges	(4,516)	(5,633)
Earnings (Loss) before Income Taxes	(11,837)	(6,458)
Income taxes (benefit)	(2,145)	(163)
Net Earnings (Loss)	(9,692)	(6,295)
Valencia non-controlling interest	0	0
Subsidiary preferred stock dividends	0	0
Net Earnings (Loss) Available for PNM Common Stock	(9,692)	(6,295)
Total Assets	218,913	201,321
Goodwill	0	0
Cost of energy
Segment Reporting Information, Profit (Loss) [Abstract]
Electric operating revenues	364,707	333,622
Cost of energy	115,396	98,710
Utility margin	249,311	234,912
Cost of energy | PNM
Segment Reporting Information, Profit (Loss) [Abstract]
Electric operating revenues	271,213	248,133
Cost of energy	88,886	74,524
Utility margin	182,327	173,609
Cost of energy | TNMP
Segment Reporting Information, Profit (Loss) [Abstract]
Electric operating revenues	93,494	85,489
Cost of energy	26,510	24,186
Utility margin	66,984	61,303
Cost of energy | Corporate and Other
Segment Reporting Information, Profit (Loss) [Abstract]
Electric operating revenues	0	0
Cost of energy	0	0
Utility margin	$ 0	$ 0

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$ 2,108,474	$ 1,741,750
Total Other Comprehensive Income (Loss)	(3,159)	(4,050)
Ending balance	2,088,226	1,687,569
Total
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(79,183)	(99,377)
Amounts reclassified from AOCI (pre-tax)	(2,155)	852
Income tax impact of amounts reclassified	547	(216)
Other OCI changes (pre-tax)	(2,079)	(6,281)
Income tax impact of other OCI changes	528	1,595
Total Other Comprehensive Income (Loss)	(3,159)	(4,050)
Ending balance	(82,342)	(103,427)
Fair Value Adjustment for Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(672)	(322)
Amounts reclassified from AOCI (pre-tax)	(624)	(38)
Income tax impact of amounts reclassified	158	10
Other OCI changes (pre-tax)	1,247	(1,998)
Income tax impact of other OCI changes	(317)	507
Total Other Comprehensive Income (Loss)	464	(1,519)
Ending balance	(208)	(1,841)
PNM
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	1,863,752	1,512,431
Total Other Comprehensive Income (Loss)	(3,623)	(2,531)
Ending balance	1,876,916	1,450,484
PNM | Total
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(78,511)	(99,055)
Amounts reclassified from AOCI (pre-tax)	(1,531)	890
Income tax impact of amounts reclassified	389	(226)
Other OCI changes (pre-tax)	(3,326)	(4,283)
Income tax impact of other OCI changes	845	1,088
Total Other Comprehensive Income (Loss)	(3,623)	(2,531)
Ending balance	(82,134)	(101,586)
PNM | Unrealized Gains on Available-for-Sale Securities
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	20,403	10,638
Amounts reclassified from AOCI (pre-tax)	(3,618)	(1,185)
Income tax impact of amounts reclassified	919	301
Other OCI changes (pre-tax)	(3,326)	(4,283)
Income tax impact of other OCI changes	845	1,088
Total Other Comprehensive Income (Loss)	(5,180)	(4,079)
Ending balance	15,223	6,559
PNM | Pension Liability Adjustment
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(98,914)	(109,693)
Amounts reclassified from AOCI (pre-tax)	2,087	2,075
Income tax impact of amounts reclassified	(530)	(527)
Total Other Comprehensive Income (Loss)	1,557	1,548
Ending balance	$ (97,357)	$ (108,145)

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Earnings Per Share [Abstract]
Net Earnings (Loss) Attributable to PNMR	$ 17,579	$ (15,260)
Average Number of Common Shares:
Outstanding during period (in shares)	85,835	79,654
Vested awards of restricted stock (in shares)	196	217
Average Shares – Basic (in shares)	86,031	79,871
Dilutive Effect of Common Stock Equivalents:
Restricted stock (in shares)	24	0
Average Shares – Diluted (in shares)	86,055	79,871
Net Earnings (Loss) Per Share of Common Stock:
Basic (in dollars per share)	$ 0.20	$ (0.19)
Diluted (in dollars per share)	$ 0.20	$ (0.19)

Electric Operating Revenues - N

Electric Operating Revenues - Narrative (Details)	3 Months Ended
	Mar. 31, 2021USD ($)utility	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)
Disaggregation of Revenue [Line Items]
Number of regulated utilities | utility	2
Accounts receivable, allowance for credit loss, period increase (decrease)	$ 1,600,000	$ 300,000
Contract assets	0		$ 0
Texas-New Mexico Power Company
Disaggregation of Revenue [Line Items]
Accounts receivable, allowance for credit loss	1,400,000
PNM
Disaggregation of Revenue [Line Items]
Accounts receivable	$ 73,200,000		$ 86,200,000

Electric Operating Revenues - D

Electric Operating Revenues - Disaggregation of revenues (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	$ 346,585	$ 322,983
Alternative revenue programs	(909)	426
Other electric operating revenue	19,031	10,213
Revenues	364,707	333,622
PNM
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	251,206	235,759
Alternative revenue programs	976	2,161
Other electric operating revenue	19,031	10,213
Revenues	271,213	248,133
TNMP
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	95,379	87,224
Alternative revenue programs	(1,885)	(1,735)
Other electric operating revenue	0	0
Revenues	93,494	85,489
Cost of energy
Disaggregation of Revenue [Line Items]
Revenues	364,707	333,622
Cost of energy | Residential
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	149,763	134,707
Cost of energy | Commercial
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	111,363	115,034
Cost of energy | Industrial
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	26,193	25,999
Cost of energy | Public authority
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	6,069	5,770
Cost of energy | Economy energy service
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	10,581	5,253
Cost of energy | PNM | Residential
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	114,669	102,809
Cost of energy | PNM | Commercial
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	81,934	86,349
Cost of energy | PNM | Industrial
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	18,900	19,466
Cost of energy | PNM | Public authority
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	4,587	4,347
Cost of energy | PNM | Economy energy service
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	10,581	5,253
Cost of energy | TNMP | Residential
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	35,094	31,898
Cost of energy | TNMP | Commercial
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	29,429	28,685
Cost of energy | TNMP | Industrial
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	7,293	6,533
Cost of energy | TNMP | Public authority
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	1,482	1,423
Cost of energy | TNMP | Economy energy service
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	0	0
Transmission
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	38,624	32,179
Transmission | PNM
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	17,503	14,167
Transmission | TNMP
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	21,121	18,012
Miscellaneous
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	3,992	4,041
Miscellaneous | PNM
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	3,032	3,368
Miscellaneous | TNMP
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	$ 960	$ 673

Variable Interest Entities (Det

Variable Interest Entities (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)MW	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)	Jan. 31, 2016USD ($)
Results of Operations
Operating revenues	$ 364,707	$ 333,622
Operating expenses	321,541	285,884
Earnings attributable to non-controlling interest	3,494	3,729
Financial Position
Current assets	328,478		$ 377,479
Assets	7,943,309	7,375,119	7,939,854
Current liabilities	1,511,120		977,662
Owners’ equity – non-controlling interest	57,260		59,009
PNM
Results of Operations
Operating revenues	271,213	248,133
Operating expenses	238,163	214,528
Earnings attributable to non-controlling interest	3,494	3,729
Financial Position
Current assets	292,085		322,128
Assets	5,561,146		5,581,033
Current liabilities	562,919		594,332
Owners’ equity – non-controlling interest	57,260		59,009
PNM | Valencia
Variable Interest Entity [Line Items]
Payment for fixed costs	4,900	5,000
Payment for variable costs	$ 200	400
Long-term contract option to purchase, ownership percentage (up to)	50.00%
Long-term contract option to purchase, purchase price - percentage of adjusted NBV	50.00%
Long-term contract option to purchase, purchase price - percentage of FMV	50.00%
Results of Operations
Operating revenues	$ 5,127	5,353
Operating expenses	1,633	1,624
Earnings attributable to non-controlling interest	3,494	$ 3,729
Financial Position
Current assets	3,282		3,911
Net property, plant, and equipment	55,035		55,744
Assets	58,317		59,655
Current liabilities	1,057		646
Owners’ equity – non-controlling interest	$ 57,260		$ 59,009
PNM | Purchased through May 2028 | Valencia
Variable Interest Entity [Line Items]
Number of megawatts purchased (in megawatts) | MW	155
NM Capital | San Juan Generating Station | Coal supply
Variable Interest Entity [Line Items]
Cash used to support bank letter or credit arrangement	$ 30,300			$ 30,300

Fair Value of Derivative and _3

Fair Value of Derivative and Other Financial Instruments - Narrative (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2021USD ($)MMBTUMW	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)MMBTU
Debt Securities, Available-for-sale [Line Items]
Obligations to return cash	$ 900,000		$ 900,000
Contract in a liability position	0		0
Debt securities, available-for-sale, unrealized loss position	0		0
Other than temporary impairments	$ 0		0
PNM
Debt Securities, Available-for-sale [Line Items]
Expected exposure to market risk (in megawatts) | MW	65
Power to be sold to third party (in megawatts) | MW	36
Amounts recognized for right to reclaim cash	$ 0		0
Cash collateral under margin arrangements	500,000		$ 500,000
(Increase)/decrease in other than temporary losses of available-for-sale securities, net portion recognized in earnings	1,100,000	$ (12,700,000)
PNM | Electricity, Purchased | Unusual Weather
Debt Securities, Available-for-sale [Line Items]
Cost of energy	20,000,000
PNM | Natural Gas Cost | Unusual Weather
Debt Securities, Available-for-sale [Line Items]
Cost of energy	$ 8,000,000
PNM | Commodity derivatives | Fair value hedging
Debt Securities, Available-for-sale [Line Items]
Economic Hedges (in mmbtu and mwh) | MMBTU	0		0
PNM | Commodity derivatives | Designated as Hedging Instrument
Debt Securities, Available-for-sale [Line Items]
Other current assets	$ 1,097,000		$ 1,096,000
PNM | Commodity derivatives | Designated as Hedging Instrument | Cost of energy
Debt Securities, Available-for-sale [Line Items]
Total gain	100,000	$ 100,000
PNM | Fuel and purchased power costs | Commodity derivatives | Designated as Hedging Instrument
Debt Securities, Available-for-sale [Line Items]
Other current assets	$ 0		0
PNM | Tri-State
Debt Securities, Available-for-sale [Line Items]
Power to be sold to third party (in megawatts) | MW	100
Recurring | PNM
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities	$ 437,028,000		440,115,000
Nuclear Decommissioning Trust | Recurring | PNM
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities	376,800,000		379,200,000
Mine Reclamation Trust | Recurring | PNM
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities	$ 60,200,000		$ 60,900,000

Fair Value of Derivative and _4

Fair Value of Derivative and Other Financial Instruments - Overview and Commodity Derivatives (Details) - PNM - Designated as Hedging Instrument - Commodity derivatives - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Other current assets	$ 1,097	$ 1,096
Other deferred charges	183	455
Derivative asset	1,280	1,551
Other current liabilities	(1,097)	(1,096)
Other deferred credits	(183)	(455)
Derivative liability	(1,280)	(1,551)
Net	$ 0	$ 0

Fair Value of Derivative and _5

Fair Value of Derivative and Other Financial Instruments - Investments in NDT and Gross Realized Losses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Equity securities:
Net gains (losses) from equity securities sold	$ 2,022	$ (1,315)
Net gains (losses) from equity securities still held	(3,166)	(18,931)
Total net gains (losses) on equity securities	(1,144)	(20,246)
Available-for-sale debt securities:
Net gains (losses) on debt securities	2,112	(12,603)
Net gains (losses) on investment securities	968	(32,849)
PNM
Available-for-sale debt securities:
Proceeds from sales	123,596	149,355
Gross realized gains	8,692	5,825
Gross realized (losses)	$ (3,443)	$ (7,035)

Fair Value of Derivative and _6

Fair Value of Derivative and Other Financial Instruments - Maturities of Debt Securities (Details) - PNMR and PNM $ in Thousands	Mar. 31, 2021USD ($)
Available-for-Sale
Within 1 year	$ 31,510
After 1 year through 5 years	71,643
After 5 years through 10 years	103,946
After 10 years through 15 years	18,105
After 15 years through 20 years	11,804
After 20 years	34,529
Available-for-sale debt securities	$ 271,537

Fair Value of Derivative and _7

Fair Value of Derivative and Other Financial Instruments - Items Recorded and Presented by Level of Hierarchy (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
PNMR	$ 3,157,858	$ 3,355,761
Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
PNMR	3,215,692	3,295,150
PNM
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
PNMR	1,561,816	1,602,547
PNM | Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
PNMR	1,697,195	1,696,620
TNMP
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
PNMR	931,042	1,006,722
TNMP | Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
PNMR	853,639	853,673
Recurring | PNM
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities	437,028	440,115
Investments, unrealized gain	20,443	27,387
Recurring | PNM | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities	190,264	183,330
Recurring | PNM | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities	246,764	256,785
Recurring | PNM | Cash and cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	11,590	6,107
Recurring | PNM | Cash and cash equivalents | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	11,590	6,107
Recurring | PNM | Cash and cash equivalents | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Recurring | PNM | Corporate stocks, common
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	86,527	85,271
Recurring | PNM | Corporate stocks, common | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	86,527	85,271
Recurring | PNM | Corporate stocks, common | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0	0
Recurring | PNM | Corporate stocks, preferred
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	9,835	9,910
Recurring | PNM | Corporate stocks, preferred | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	3,456	3,608
Recurring | PNM | Corporate stocks, preferred | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	6,379	6,302
Recurring | PNM | Mutual funds and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	57,539	58,817
Recurring | PNM | Mutual funds and other | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	57,498	58,762
Recurring | PNM | Mutual funds and other | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	41	55
Recurring | PNM | Corporate stocks, common
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, unrealized gain
Recurring | PNM | Corporate stocks, preferred
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, unrealized gain
Recurring | PNM | Mutual funds and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, unrealized gain
Recurring | PNM | U.S. government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities	58,575	55,839
Investments, unrealized gain	388	950
Recurring | PNM | U.S. government | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities	31,193	29,579
Recurring | PNM | U.S. government | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities	27,382	26,260
Recurring | PNM | International government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities	15,380	16,032
Investments, unrealized gain	1,641	2,537
Recurring | PNM | International government | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities	0	0
Recurring | PNM | International government | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities	15,380	16,032
Recurring | PNM | Municipals
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities	47,188	50,139
Investments, unrealized gain	2,080	2,779
Recurring | PNM | Municipals | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities	0	0
Recurring | PNM | Municipals | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities	47,188	50,139
Recurring | PNM | Corporate and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities	150,394	158,000
Investments, unrealized gain	16,334	21,121
Recurring | PNM | Corporate and other | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities	0	3
Recurring | PNM | Corporate and other | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities	$ 150,394	$ 157,997

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Details) $ in Millions	3 Months Ended	123 Months Ended
	Mar. 31, 2021USD ($)shares	Mar. 31, 2021USD ($)shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)		0
Restricted Shares and Performance Based Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized expense related to stock awards | $	$ 6.7	$ 6.7
Period of time stock expense is expected to be recognized	2 years 1 month 6 days
Executive | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares awarded in year one (in shares)	142,080	142,080
Maximum number of shares awarded in year two (in shares)	142,047	142,047
Maximum number of shares awarded in year three (in shares)	152,414	152,414
Performance period	3 years
Executive | Performance Shares | Achieved performance target for 2017 through 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares awarded in year one (in shares)	124,941	124,941
Performance Equity Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Vesting rate	100.00%
Performance Equity Plan | Non-employee Members of the Board of Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year

Stock-Based Compensation (Detai

Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Total intrinsic value of options exercised	$ 0	$ 84
Restricted Shares and Performance Based Shares
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected quarterly dividends per share (in dollars per share)	$ 0.3275	$ 0.3075
Risk-free interest rate	0.32%	0.72%
Restricted Stock
Restricted Stock, Shares
Outstanding at beginning of period (in shares)	168,061
Granted (in shares)	194,075
Exercised (in shares)	(189,098)
Forfeited (in shares)	(851)
Outstanding at end of period (in shares)	172,187
Restricted Stock, Weighted- Average Grant Date Fair Value
Outstanding at beginning of period (in dollars per share)	$ 40.77
Granted (in dollars per share)	43.68	$ 36.88
Exercised (in dollars per share)	42.26
Forfeited (in dollars per share)	43.77
Outstanding at end of period (in dollars per share)	42.41
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted-average grant date fair value (in dollars per share)	$ 43.68	$ 36.88
Total fair value of restricted shares that vested	$ 8,967	$ 11,269
Market-Based Shares
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Risk-free interest rate	0.29%	0.72%
Dividend yield	2.76%	2.51%
Expected volatility	33.69%	19.41%

Financing - Financing Activitie

Financing - Financing Activities (Details) - USD ($)	Mar. 09, 2021	Dec. 22, 2020	Apr. 14, 2020	Mar. 31, 2021	Aug. 31, 2020	Mar. 09, 2018
PNMR Revolving Credit Facility
Debt Instrument [Line Items]
Proceeds from short-term debt	$ 80,000,000
PNMR 2015 Term Loan Agreement
Debt Instrument [Line Items]
Term loans						$ 150,000,000
PNMR 2020 Delayed-Draw Term Loan
Debt Instrument [Line Items]
Aggregate principal amount		$ 300,000,000
Term loans				$ 300,000,000
Proceeds from issuance of debt		$ 80,000,000
Variable interest rate				1.36%
PNMR 2019 Term Loan
Debt Instrument [Line Items]
Variable interest rate				1.07%
PNMR 2020 Term Loan
Debt Instrument [Line Items]
Variable interest rate				1.21%
PNM | PNM 2019 40 Million Term Loan
Debt Instrument [Line Items]
Aggregate principal amount				$ 40,000,000
Variable interest rate				0.76%
PNM | Maximum
Debt Instrument [Line Items]
Maturity term over which financings require regulator approval (more than)				18 months
PNMR | PNMR 2020 Delayed-Draw Term Loan
Debt Instrument [Line Items]
Remaining borrowing capacity	$ 220,000,000
PNMR | PNMR 2020 Term Loan
Debt Instrument [Line Items]
Term loans				$ 150,000,000
PNMR | PNMR Development Term Loan
Debt Instrument [Line Items]
Term loans				$ 65,000,000
Texas-New Mexico Power Company
Debt Instrument [Line Items]
Proceeds from short-term debt			$ 500,000
Line of credit | PNMR and PNMR Development
Debt Instrument [Line Items]
Ratio of debt to capital (less than or equal to)				70.00%
Line of credit | PNM and TNMP
Debt Instrument [Line Items]
Ratio of debt to capital (less than or equal to)				65.00%
Letter of credit | PNMR | WFB LOC Facility
Debt Instrument [Line Items]
Aggregate principal amount					$ 30,300,000
Unsecured Debt | PNMR 2018 SUNS 3.25 percent due March 2021
Debt Instrument [Line Items]
Aggregate principal amount						$ 300,000,000
Stated interest rate						3.25%
Unsecured Debt | PNM | PNM 2019 40 Million Term Loan
Debt Instrument [Line Items]
Term loans				$ 40,000,000
Mortgage Bonds | Texas-New Mexico Power Company | TNMP First Mortgage Bonds
Debt Instrument [Line Items]
Aggregate principal amount				$ 750,000,000
Debt instrument, prepayment period				30 days
Debt instrument, redemption price, percentage of principal amount redeemed				100.00%
Bonds | Pollution Control Revenue Bonds
Debt Instrument [Line Items]
Variable interest rate				0.14%
Term loan agreement with banks | Texas-New Mexico Power Company | PNMR Development Term Loan
Debt Instrument [Line Items]
Variable interest rate				1.48%

Financing - Short-term Debt and

Financing - Short-term Debt and Liquidity (Details)	Jul. 22, 2019USD ($)	Mar. 31, 2021USD ($)extension_option	Dec. 31, 2017USD ($)derivative	Apr. 23, 2021USD ($)	Mar. 23, 2021	Mar. 09, 2021USD ($)	Dec. 31, 2020USD ($)	Dec. 22, 2020USD ($)	Jul. 21, 2019USD ($)
Short-term Debt [Line Items]
Financing capacity	$ 50,000,000								$ 40,000,000
Advanced notice period prior to increasing capacity of the facility	15 days
Short-term debt		$ 197,500,000					$ 32,000,000
Letters of credit outstanding		3,400,000
Notes payable, related parties		32,400,000					0
Variable Rate Short-Term Debt
Short-term Debt [Line Items]
Term of derivatives			4 years
Aggregate principal amount			$ 50,000,000
PNMR 2020 Delayed-Draw Term Loan
Short-term Debt [Line Items]
Aggregate principal amount								$ 300,000,000
Long-term debt		$ 300,000,000
TNMP Revolving Credit Facility
Short-term Debt [Line Items]
Line of credit facility, interest rate at period end		0.86%
PNMR Revolving Credit Facility
Short-term Debt [Line Items]
Short-term debt		$ 114,400,000					12,000,000
PNMR Revolving Credit Facility | PNMR
Short-term Debt [Line Items]
Line of credit facility, interest rate at period end		1.61%
PNMR Development Revolving Credit Facility
Short-term Debt [Line Items]
Short-term debt		$ 40,000,000					10,000,000
Line of credit facility, interest rate at period end		1.11%
PNM
Short-term Debt [Line Items]
Short-term debt		$ 0					10,000,000
Letters of credit outstanding		2,200,000
Notes payable, related parties		0					0
PNM | Lines of credit
Short-term Debt [Line Items]
NMPRC approved credit facility		40,000,000
PNM | PNM 2019 40 Million Term Loan
Short-term Debt [Line Items]
Aggregate principal amount		40,000,000
PNM | PNM 2019 40 Million Term Loan | Unsecured Debt
Short-term Debt [Line Items]
Long-term debt		40,000,000
PNM | Senior Unsecured Notes, PCRB due 2033 at 1.875% | Senior Unsecured Notes, Pollution Control Revenue Bonds
Short-term Debt [Line Items]
Unsecured long-term debt, noncurrent		146,000,000
PNM | Senior Unsecured Notes, due 2021, at 5.35% | Unsecured Debt
Short-term Debt [Line Items]
Unsecured long-term debt, noncurrent		160,000,000
PNM | PNM Revolving Credit Facility
Short-term Debt [Line Items]
Short-term debt		0					0
PNM | PNM 2017 New Mexico Credit Facility
Short-term Debt [Line Items]
Short-term debt		0					10,000,000
PNM | PNMR Development Revolving Credit Facility
Short-term Debt [Line Items]
Letters of credit outstanding		0
TNMP
Short-term Debt [Line Items]
Short-term debt		43,100,000					0
Letters of credit outstanding		0
Notes payable, related parties		0					0
TNMP | TNMP Revolving Credit Facility
Short-term Debt [Line Items]
Short-term debt		43,100,000					0
PNMR Development
Short-term Debt [Line Items]
Notes payable, related parties		0					300,000
PNMR | PNM 2019 Term Loan
Short-term Debt [Line Items]
Long-term debt		150,000,000
PNMR | PNMR 2020 Term Loan
Short-term Debt [Line Items]
Long-term debt		150,000,000
PNMR | PNMR 2020 Delayed-Draw Term Loan
Short-term Debt [Line Items]
Remaining borrowing capacity						$ 220,000,000
PNMR | PNMR Development Term Loan
Short-term Debt [Line Items]
Long-term debt		65,000,000
Revolving credit facility
Short-term Debt [Line Items]
Financing capacity		300,000,000
Revolving credit facility | PNM
Short-term Debt [Line Items]
Financing capacity		400,000,000
Revolving credit facility | TNMP
Short-term Debt [Line Items]
Financing capacity		75,000,000
Revolving credit facility | TNMP | First mortgage bonds
Short-term Debt [Line Items]
Collateral amount		$ 75,000,000
Number of extension options | extension_option		2
Extension option period		1 year
Interest rate contract
Short-term Debt [Line Items]
Number of derivatives | derivative			3
Interest rate 1 | Variable Rate Short-Term Debt
Short-term Debt [Line Items]
Fixed interest rate			1.926%		1.926%
Interest rate 2 | Variable Rate Short-Term Debt
Short-term Debt [Line Items]
Fixed interest rate			1.823%
Interest rate 3 | Variable Rate Short-Term Debt
Short-term Debt [Line Items]
Fixed interest rate			1.629%
Interest rate 3 | Level 2 | Cash Flow Hedge
Short-term Debt [Line Items]
Current derivative liability		$ 300,000					$ 900,000
Subsequent event
Short-term Debt [Line Items]
Notes payable, related parties				$ 32,400,000
Remaining borrowing capacity				644,800,000
Subsequent event | PNMR
Short-term Debt [Line Items]
Remaining borrowing capacity				184,400,000
Consolidated invested cash				900,000
Subsequent event | Pollution Control Revenue Bonds | Bonds
Short-term Debt [Line Items]
Aggregate principal amount				100,300,000
Subsequent event | PNM
Short-term Debt [Line Items]
Notes payable, related parties				0
Remaining borrowing capacity				395,900,000
Consolidated invested cash				0
Subsequent event | PNM | Lines of credit
Short-term Debt [Line Items]
Remaining borrowing capacity				40,000,000
Subsequent event | TNMP
Short-term Debt [Line Items]
Notes payable, related parties				0
Remaining borrowing capacity				24,500,000
Consolidated invested cash				0
Subsequent event | PNMR Development
Short-term Debt [Line Items]
Notes payable, related parties				0
Remaining borrowing capacity				$ 0

Pension and Other Postretirem_3

Pension and Other Postretirement Benefit Plans (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
PNM | Pension Plan
Components of Net Periodic Benefit Cost
Service cost	$ 0	$ 0
Interest cost	4,036,000	4,985,000
Expected return on plan assets	(7,133,000)	(7,363,000)
Amortization of net loss	4,541,000	4,465,000
Amortization of prior service cost	0	(138,000)
Net Periodic Benefit Cost (Income)	1,444,000	1,949,000
Contributions by employer	0	0
Expected employer contributions, remainder of fiscal year	0
Expected employer contributions in year 2	10,800,000
Expected employer contributions in year 3	11,500,000
Expected employer contributions in year 4	$ 10,600,000
PNM | Pension Plan | Maximum
Components of Net Periodic Benefit Cost
Assumptions used calculating net periodic benefit cost, discount rate	2.90%
PNM | OPEB Plan
Components of Net Periodic Benefit Cost
Service cost	$ 6,000	10,000
Interest cost	477,000	613,000
Expected return on plan assets	(1,042,000)	(1,387,000)
Amortization of net loss	0	87,000
Amortization of prior service cost	0	0
Net Periodic Benefit Cost (Income)	(559,000)	(677,000)
Contributions by employer	0	0
Disbursements by employer	900,000	1,100,000
Expected employer disbursements for remainder of fiscal year	3,300,000
Expected employer disbursements in year 2 through 5	13,100,000
PNM | Executive Retirement Program
Components of Net Periodic Benefit Cost
Service cost	0	0
Interest cost	90,000	122,000
Expected return on plan assets	0	0
Amortization of net loss	100,000	101,000
Amortization of prior service cost	0	0
Net Periodic Benefit Cost (Income)	190,000	223,000
Disbursements by employer	400,000	300,000
Expected employer disbursements for remainder of fiscal year	1,300,000
Expected employer disbursements in year 2 through 5	4,900,000
TNMP | Pension Plan
Components of Net Periodic Benefit Cost
Service cost	0	0
Interest cost	435,000	544,000
Expected return on plan assets	(795,000)	(821,000)
Amortization of net loss	312,000	315,000
Amortization of prior service cost	0	0
Net Periodic Benefit Cost (Income)	(48,000)	38,000
Contributions by employer	0	0
Estimated employer contributions remainder of fiscal year through year two	$ 0
TNMP | Pension Plan | Maximum
Components of Net Periodic Benefit Cost
Assumptions used calculating net periodic benefit cost, discount rate	2.90%
TNMP | OPEB Plan
Components of Net Periodic Benefit Cost
Service cost	$ 11,000	12,000
Interest cost	77,000	93,000
Expected return on plan assets	(102,000)	(134,000)
Amortization of net loss	(80,000)	(81,000)
Amortization of prior service cost	0	0
Net Periodic Benefit Cost (Income)	(94,000)	(110,000)
Contributions by employer	0	0
Estimated employer contributions for remainder of fiscal year through year 5	0
TNMP | Executive Retirement Program
Components of Net Periodic Benefit Cost
Service cost	0	0
Interest cost	4,000	6,000
Expected return on plan assets	0	0
Amortization of net loss	9,000	6,000
Amortization of prior service cost	0	0
Net Periodic Benefit Cost (Income)	13,000	12,000
Expected employer disbursements for remainder of fiscal year	100,000
Expected employer disbursements in year 2 through 5	300,000
TNMP | Executive Retirement Program | Maximum
Components of Net Periodic Benefit Cost
Disbursements by employer	$ 0	$ 0

Commitments and Contingencies -

Commitments and Contingencies - Nuclear Spent Fuel and Waste Disposal (Details) - PNM - Nuclear spent fuel and waste disposal - Palo Verde Nuclear Generating Station - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Public Utilities, Commitments And Contingencies [Line Items]
Estimate of possible loss	$ 59.6
Other deferred credits
Public Utilities, Commitments And Contingencies [Line Items]
Loss contingency accrual	$ 12.8	$ 12.8

Commitments and Contingencies_2

Commitments and Contingencies - The Energy Transition Act (Details) - Electric-Generation Portfolio Standard - Energy Transition Act	Jun. 14, 2019
Required Percentage by 2025
Public Utilities, Commitments And Contingencies [Line Items]
Renewable energy, percentage	0.40
Required Percentage by 2030
Public Utilities, Commitments And Contingencies [Line Items]
Renewable energy, percentage	0.50
Required Percentage by 2040
Public Utilities, Commitments And Contingencies [Line Items]
Renewable energy, percentage	0.80
Required Percentage by 2045
Public Utilities, Commitments And Contingencies [Line Items]
Renewable energy, percentage	1

Commitments and Contingencies_3

Commitments and Contingencies - The Clean Air Act (Details)	3 Months Ended
	Mar. 31, 2021optionT	Feb. 25, 2019parts_per_billion	Oct. 01, 2015parts_per_billion	Sep. 30, 2015parts_per_billion	Dec. 31, 1999state
Public Utilities, Commitments And Contingencies [Line Items]
Number of options for meeting BTA standards | option	7
Clean Air Act related to regional haze
Public Utilities, Commitments And Contingencies [Line Items]
Number of states to address regional haze (in states) | state					50
Potential to emit tons per year of visibility impairing pollution (in tons, more than) | T	250
Maximum | PNM | San Juan Generating Station and Four Corners
Public Utilities, Commitments And Contingencies [Line Items]
Government standard emission limit (in ozone parts per million) | parts_per_billion		75	70	75

Commitments and Contingencies_4

Commitments and Contingencies - Coal Supply (Details) - USD ($)	1 Months Ended	3 Months Ended	12 Months Ended
	Dec. 31, 2020	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Mar. 31, 2020	Jan. 31, 2016
Public Utilities, Commitments And Contingencies [Line Items]
Other current assets	$ 64,549,000	$ 60,764,000	$ 64,549,000
PNM
Public Utilities, Commitments And Contingencies [Line Items]
Other current assets	51,908,000	50,441,000	51,908,000
PNM | Loss on long-term purchase commitment | Surface
Public Utilities, Commitments And Contingencies [Line Items]
Loss contingency accrual	71,700,000	70,400,000	71,700,000
PNM | Loss on long-term purchase commitment | Underground
Public Utilities, Commitments And Contingencies [Line Items]
Loss contingency accrual	26,100,000	26,600,000	26,100,000
PNM | Loss on long-term purchase commitment | San Juan Generating Station | Surface
Public Utilities, Commitments And Contingencies [Line Items]
Estimate of possible loss		78,400,000
PNM | Loss on long-term purchase commitment | San Juan Generating Station | Underground
Public Utilities, Commitments And Contingencies [Line Items]
Estimate of possible loss		35,100,000
Coal supply | Four Corners
Public Utilities, Commitments And Contingencies [Line Items]
Payments for relief from obligations		75,000,000
Coal supply | PNM | San Juan Generating Station
Public Utilities, Commitments And Contingencies [Line Items]
Other current assets	26,300,000	24,800,000	26,300,000
Coal supply | NM Capital | San Juan Generating Station
Public Utilities, Commitments And Contingencies [Line Items]
Requirement to post reclamation bonds		118,700,000
Cash used to support bank letter or credit arrangement		30,300,000				$ 30,300,000
Increase in coal mine decommissioning liability | PNM
Public Utilities, Commitments And Contingencies [Line Items]
Regulatory disallowance, additional amount recorded				$ 800,000
Increase in coal mine decommissioning liability | PNM | Surface
Public Utilities, Commitments And Contingencies [Line Items]
Regulatory disallowance, additional amount recorded	3,600,000
Decrease in coal mine decommissioning liability | PNM | Underground
Public Utilities, Commitments And Contingencies [Line Items]
Regulatory disallowance, additional amount recorded	$ 100,000
Decrease in coal mine decommissioning liability | PNM | Four Corners
Public Utilities, Commitments And Contingencies [Line Items]
Regulatory disallowance, additional amount recorded			2,500,000
Mine Reclamation Trust | PNM
Public Utilities, Commitments And Contingencies [Line Items]
Required contribution to reclamation trust, current fiscal year		5,500,000
Reclamation trust funding, year 2		6,200,000
Reclamation trust funding, year 3		0
Four Corners CSA | PNM
Public Utilities, Commitments And Contingencies [Line Items]
Other commitment, due in first year					$ 2,000,000
Other commitment, due in second year		2,100,000
Other commitment, due in third year		2,100,000
Other commitment, due in fourth year		2,100,000
Other commitment, due in fifth year		$ 2,100,000
San Juan Generating Station | Loss on long-term purchase commitment | PNM
Public Utilities, Commitments And Contingencies [Line Items]
Annual funding post-term reclamation trust			$ 3,200,000

Commitments and Contingencies_5

Commitments and Contingencies - Royalty Rates, Tax Assessment, Insurance and Other Matters (Details)	1 Months Ended	3 Months Ended
	Sep. 30, 2012landowner	Mar. 31, 2021USD ($)lawsuitplaintiffgenerating_unitshareholder	Dec. 01, 2015Allotment_Parcel	Jul. 13, 2015a	Jan. 22, 2015Allotment_Parcel	Aug. 31, 2013
Continuous highwall mining | San Juan Generating Station
Public Utilities, Commitments And Contingencies [Line Items]
Proposed retroactive surface mining royalty rate						12.50%
Surface mining royalty rate applied		8.00%
Estimated underpaid surface mining royalties under proposed rate change		$ 5,000,000
PNM's share estimated underpaid surface mining royalties under proposed rate change		46.30%
Merger-Related Litigation
Public Utilities, Commitments And Contingencies [Line Items]
Number of shareholders involved in lawsuit | shareholder		6
Number of lawsuits for the Southern District of New York | lawsuit		5
Number of lawsuits filed for the Eastern District of New York | lawsuit		1
Number of plaintiffs who filed notices of voluntary dismissal | plaintiff		5
PNM | Navajo Nation Allottee Matters
Public Utilities, Commitments And Contingencies [Line Items]
Number of landowners involved in the appeal | landowner	43
Number of allotments where landowners are revoking rights of way renewal consents (in allotment parcels) | Allotment_Parcel			2		10
Area of land (in acres) | a				15.49
Number of allotment parcels at issue that are not to be condemned | Allotment_Parcel			2
Number of allotment parcels at issue | Allotment_Parcel			5
PNM | Palo Verde Nuclear Generating Station | Nuclear plant
Public Utilities, Commitments And Contingencies [Line Items]
Ownership percentage in nuclear reactor		10.20%
Number of units | generating_unit		3
Maximum potential assessment per incident		$ 42,100,000
Annual payment limitation related to incident		6,200,000
Aggregate amount of all risk insurance		2,800,000,000
Maximum amount under Nuclear Electric Insurance Limited		5,400,000
PNM | Maximum | Palo Verde Nuclear Generating Station | Nuclear plant
Public Utilities, Commitments And Contingencies [Line Items]
Liability insurance coverage		13,700,000,000
Liability insurance coverage sublimit		2,250,000,000
Commercial providers | PNM | Palo Verde Nuclear Generating Station | Nuclear plant
Public Utilities, Commitments And Contingencies [Line Items]
Liability insurance coverage		450,000,000
Industry Wide Retrospective Assessment Program | PNM | Palo Verde Nuclear Generating Station | Nuclear plant
Public Utilities, Commitments And Contingencies [Line Items]
Liability insurance coverage		$ 13,200,000,000

Regulatory and Rate Matters - P

Regulatory and Rate Matters - PNM (Details)	Apr. 15, 2021USD ($)GWh	Jan. 29, 2021	Jan. 01, 2021USD ($)	Apr. 15, 2020USD ($)MMBTUmeter	Mar. 31, 2021USD ($)MW	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)GWh	Jul. 29, 2020MW
Public Utilities, Commitments And Contingencies [Line Items]
Excess return on jurisdictional equity that would require refund					0.50%
PNM
Public Utilities, Commitments And Contingencies [Line Items]
Solar generation capacity (in megawatts) | MW								650
Renewable Portfolio Standard | PNM
Public Utilities, Commitments And Contingencies [Line Items]
Number of megawatts of Solar PV facilities | MW					158
Current output in the geothermal facility (in megawatts) | MW					11
Solar generation capacity (in megawatts) | MW					169.5
Energy Efficiency and Load Management Program | PNM
Public Utilities, Commitments And Contingencies [Line Items]
Energy efficiency and load management programs targeted energy savings (in Gigawatts) | MMBTU				80
Program costs related to energy efficiency, in year two				$ 31,400,000
Program costs related to energy efficiency, in year three				31,000,000
Program costs related to energy efficiency, in year four				$ 29,600,000
Number of AMI meters to be installed | meter				5,000
Program costs related to meter installation				$ 2,900,000
Integrated Resource Plan, 2011 | PNM
Public Utilities, Commitments And Contingencies [Line Items]
Frequency of IRP filings					3 years
Planning period covered of IRP					20 years
Integrated Resource Plan, 2020 | PNM
Public Utilities, Commitments And Contingencies [Line Items]
Planning period covered of IRP		20 years
NMPRC
Public Utilities, Commitments And Contingencies [Line Items]
Action plan, covered period					4 years
NMPRC | PNM
Public Utilities, Commitments And Contingencies [Line Items]
Proposed revision to rider that will allow for recovery			$ 67,800,000
NMPRC | Renewable Energy Rider | PNM
Public Utilities, Commitments And Contingencies [Line Items]
Renewable energy procurement plan, approved recovery, amount			65,500,000
Recorded revenues from renewable rider					$ 15,900,000	$ 15,100,000
NMPRC | Renewable Energy Rider, Sky Blue Energy Program | PNM
Public Utilities, Commitments And Contingencies [Line Items]
Proposed revision to rider that will allow for recovery			$ 2,300,000
Maximum | Renewable Portfolio Standard | PNM
Public Utilities, Commitments And Contingencies [Line Items]
Reasonable cost threshold in megawatts per hour					$ 60
Minimum | Renewable Portfolio Standard | PNM
Public Utilities, Commitments And Contingencies [Line Items]
Profit incentive sliding scale multiplier				0.071			0.071
Energy efficiency and load management programs targeted energy savings (in Gigawatts) | MMBTU				80
New Mexico Wind | Renewable Portfolio Standard 2014 | PNM
Public Utilities, Commitments And Contingencies [Line Items]
Number of megawatts for wind energy | MW					200
Red Mesa Wind | Renewable Portfolio Standard 2014 | PNM
Public Utilities, Commitments And Contingencies [Line Items]
Number of megawatts for wind energy | MW					102
La Joya Wind | Renewable Portfolio Standard | PNM
Public Utilities, Commitments And Contingencies [Line Items]
Number of megawatts for wind energy | MW					140
Disincentives and Incentives Added | 2017 Energy Efficiency and Load Management Program | PNM
Public Utilities, Commitments And Contingencies [Line Items]
Energy efficiency and load management programs profit incentive, minimum							$ 1,800,000
Energy efficiency and load management programs targeted energy savings (in Gigawatts) | GWh							59
Energy efficiency and load management programs additional incentive targeted energy savings (in Gigawatts) | GWh							68
Disincentives and Incentives Added | 2020 Energy Efficiency Annual Report | PNM | Subsequent event
Public Utilities, Commitments And Contingencies [Line Items]
Energy efficiency and load management programs additional incentive targeted energy savings (in Gigawatts) | GWh	87
Energy efficiency and load management programs	$ 800,000

Regulatory and Rate Matters - S

Regulatory and Rate Matters - SJGS, Fours Corners and PVNGS Leased Interest Abandonment Applications (Details) $ in Thousands

Apr. 02, 2021leaseMW

Feb. 03, 2021

Jan. 08, 2021USD ($)

Nov. 01, 2020USD ($)

Jul. 01, 2019USD ($)

Nov. 30, 2020USD ($)

Apr. 14, 2021MW

Mar. 31, 2021USD ($)MW

Mar. 12, 2021MW

Feb. 08, 2021MW

Jan. 28, 2021MW

Dec. 31, 2020USD ($)

Dec. 18, 2020USD ($)

Nov. 13, 2020MW

Sep. 28, 2020USD ($)

Jul. 29, 2020MW

Mar. 31, 2020USD ($)

Feb. 21, 2020USD ($)

Public Utilities, General Disclosures [Line Items]

Ownership percentage

50.00%

Regulatory assets

$ 555,150

$ 557,790

Regulatory liabilities

854,748

850,228

Subsequent event

Public Utilities, General Disclosures [Line Items]

Regulatory time frame for proposed PPAs and battery storage agreements

6 months

COVID-19

Public Utilities, General Disclosures [Line Items]

Temporary mandatory moratorium on disconnection period

100 days

Disconnection transition period

90 days

Facebook Data Center

Public Utilities, General Disclosures [Line Items]

Solar generation capacity (in megawatts) | MW

190

Number of megawatts in battery storage facilities (in megawatts) | MW

100

Solar generation capacity expected to be operational (in megawatts) | MW

50

Facebook Data Center | Subsequent event

Public Utilities, General Disclosures [Line Items]

Number of megawatts in battery storage facilities (in megawatts) | MW

100

PNM

Public Utilities, General Disclosures [Line Items]

Solar generation capacity (in megawatts) | MW

650

Number of megawatts in battery storage facilities (in megawatts) | MW

300

Regulatory assets

456,374

457,953

Regulatory liabilities

663,429

664,873

Solar generation capacity related to unexecuted transmission service agreement (in megawatts) | MW

145

PNM | Four Corners

Public Utilities, General Disclosures [Line Items]

Request issuance of energy transition bonds

$ 300,000

Forecasted undepreciated investment

272,000

Plant decommissioning and coal mine reclamation costs

4,600

Upfront financing costs

7,300

Proceeds from securitization bonds

$ 16,500

Solar generation capacity (in megawatts) | MW

200

Payments for relief from obligations

$ 75,000

$ 15,000

Final payment for relief from obligations

60,000

Initial payment for relief from obligations

$ 15,000

PNM | Four Corners | PNM

Public Utilities, General Disclosures [Line Items]

Noncontrolling interest, ownership percentage by noncontrolling owners

13.00%

PNM | COVID-19 | COVID-19 Costs Savings

Public Utilities, General Disclosures [Line Items]

Regulatory liabilities

900

900

PNM | Deferred COVID-19 Costs | COVID-19

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 10,700

8,800

PNM | Subsequent event

Public Utilities, General Disclosures [Line Items]

Number of leases under which lease term was extended | lease

5

PNM | NMPRC | Subsequent event

Public Utilities, General Disclosures [Line Items]

Solar generation capacity, amount requested for approval to abandon (in megawatts) | MW

114

PNM | Leased Interest Termination on January 15, 2023 | Subsequent event

Public Utilities, General Disclosures [Line Items]

Number of leases under which lease term was extended | lease

4

PNM | Leased Interest Termination on January 15, 2023 | NMPRC | Subsequent event

Public Utilities, General Disclosures [Line Items]

Solar generation capacity (in megawatts) | MW

104

PNM | Leased Interest Termination on January 15, 2024 | NMPRC | Subsequent event

Public Utilities, General Disclosures [Line Items]

Solar generation capacity (in megawatts) | MW

10

PNM | Replacement Resource Portfolio One

Public Utilities, General Disclosures [Line Items]

Solar generation capacity (in megawatts) | MW

200

Number of megawatts in battery storage facilities (in megawatts) | MW

100

PNM | Replacement Resource Portfolio One | Subsequent event

Public Utilities, General Disclosures [Line Items]

Solar generation capacity (in megawatts) | MW

150

Number of megawatts in battery storage facilities (in megawatts) | MW

40

PNM | Replacement Resource Portfolio Two

Public Utilities, General Disclosures [Line Items]

Solar generation capacity (in megawatts) | MW

100

Number of megawatts in battery storage facilities (in megawatts) | MW

30

PNM | Replacement Resource Portfolio Two | Subsequent event

Public Utilities, General Disclosures [Line Items]

Number of megawatts in battery storage facilities (in megawatts) | MW

100

PNM | Replacement Resource Portfolio Three | Subsequent event

Public Utilities, General Disclosures [Line Items]

Solar generation capacity (in megawatts) | MW

300

Number of megawatts in battery storage facilities (in megawatts) | MW

150

PNM | Transportation Electrification Program

Public Utilities, General Disclosures [Line Items]

Expected budgeted expenditures

$ 8,400

Budget flexibility (percent)

25.00%

Budget portion dedicated to low and moderate income customers (percent)

25.00%

PNMR Development

Public Utilities, General Disclosures [Line Items]

Solar generation capacity (in megawatts) | MW

130

Ownership percentage

50.00%

San Juan Generating Station

Public Utilities, General Disclosures [Line Items]

Estimated costs of replacement resources

$ 8,100

San Juan Generating Station | Other deferred credits

Public Utilities, General Disclosures [Line Items]

Restructuring reserve

38,100

San Juan Generating Station | Employee Severance

Public Utilities, General Disclosures [Line Items]

Restructuring reserve

$ 9,400

San Juan Generating Station | PNM

Public Utilities, General Disclosures [Line Items]

Request issuance of energy transition bonds

$ 361,000

Forecasted undepreciated investment

283,000

$ 361,000

Plant decommissioning and coal mine reclamation costs

28,600

Upfront financing costs

9,600

Severance costs

20,000

Proceeds from securitization bonds

$ 19,800

San Juan Generating Station | PNM | Other deferred credits

Public Utilities, General Disclosures [Line Items]

Restructuring reserve

$ 36,800

San Juan Generating Station | PNM | Employee Severance

Public Utilities, General Disclosures [Line Items]

Restructuring reserve

8,100

San Juan Generating Station | PNM | Other Restructuring

Public Utilities, General Disclosures [Line Items]

Restructuring reserve

8,900

San Juan Generating Station | PNM | Economic Development and Workforce Training Costs

Public Utilities, General Disclosures [Line Items]

Restructuring reserve

$ 19,800

Regulatory and Rate Matters - T

Regulatory and Rate Matters - TNMP Narrative (Details) - TNMP $ in Millions

Apr. 05, 2021USD ($)

Jun. 26, 2020USD ($)

Apr. 14, 2020USD ($)

Apr. 06, 2020USD ($)

Oct. 31, 2019USD ($)

Aug. 31, 2019USD ($)

Mar. 31, 2021USD ($)

Mar. 01, 2021USD ($)

Dec. 31, 2020USD ($)

Oct. 02, 2020USD ($)

Mar. 30, 2020MWh

Mar. 01, 2020USD ($)

Dec. 31, 2019USD ($)

Public Utilities, Commitments And Contingencies [Line Items]

Requested increase in annual distribution revenue

$ 14.7

Incremental distribution investments

$ 149.2

Annual distribution revenue requirement

$ 14.3

Energy efficiency cost recovery, requested change amount

$ 5.9

$ 5.9

Energy efficiency cost recovery, requested bonus

$ 1

$ 0.8

Rider charge from electricity relief program (per MWh) | MWh

0.33

Proceeds from short-term debt

$ 0.5

Public utilities, estimate of possible upgrades

$ 46

Subsequent event

Public Utilities, Commitments And Contingencies [Line Items]

Requested increase in annual distribution revenue

$ 14

Increase in revenue base rate

$ 104.5

COVID-19

Public Utilities, Commitments And Contingencies [Line Items]

Regulatory liability

$ 0.1

$ 0.1

Other COVID-19 related costs

$ 0.8

$ 0.7

2018 TNMP Rate Case

Public Utilities, Commitments And Contingencies [Line Items]

Recovery of costs incurred

$ 3.3

$ 3.8

Recovery costs collection period

3 years

Write off of regulatory disallowance

$ 0.5

Regulatory and Rate Matters -_2

Regulatory and Rate Matters - Transmission Cost of Service Rates (Details) - PUCT - TNMP - USD ($) $ in Millions	Mar. 12, 2021	Oct. 07, 2020	Mar. 27, 2020
Public Utilities, General Disclosures [Line Items]
Approved Increase in Rate Base	$ 112.6	$ 10.8	$ 59.2
Annual Increase in Revenue	$ 14.1	$ 2	$ 7.8

Lease Commitments - Narrative (

Lease Commitments - Narrative (Details) $ in Millions	1 Months Ended	3 Months Ended
	Apr. 30, 2021USD ($)	Mar. 31, 2021USD ($)	Mar. 31, 2020USD ($)	Apr. 02, 2021lease	Dec. 31, 2020USD ($)	Jan. 15, 2016lease	Jan. 15, 2015lease
Operating Leased Assets [Line Items]
Operating lease, payments to lessor upon occurrence of certain events		$ 146.5
Unamortized cost, right-of-way lease payments		55.1			$ 55.8
Operating lease, right-of-use assets, amortization expense		1	$ 0.9
Operating leases, capitalized financing costs, investing activities		0.8	0.9
Finance leases, capitalized financing costs, investing activities		1	0.5
Lessee, operating lease, unguaranteed residual value		26.1
PNM
Operating Leased Assets [Line Items]
Operating leases, capitalized financing costs, investing activities		0.2	0.3
Finance leases, capitalized financing costs, investing activities		0.4	0.2
Lessee, operating lease, unguaranteed residual value		11
PNM | Subsequent event
Operating Leased Assets [Line Items]
Number of leases under which lease term was extended | lease				5
PNM | Palo Verde Nuclear Generating Station, Unit 1 and 4 Leases
Operating Leased Assets [Line Items]
Number of leases, expiring | lease							4
Number of leases under which lease term was extended | lease							4
Annual lease payments during renewal period		16.5
PNM | Palo Verde Nuclear Generating Station, Unit 2 Leases
Operating Leased Assets [Line Items]
Number of leases, expiring | lease						4
Number of leases under which lease term was extended | lease						1
Annual lease payments during renewal period		1.6
PNM | Navajo Nation
Operating Leased Assets [Line Items]
Annual lease payments		6
PNM | Navajo Nation | Subsequent event
Operating Leased Assets [Line Items]
Right-of-way lease payments	$ 7.3
TNMP
Operating Leased Assets [Line Items]
Operating leases, capitalized financing costs, investing activities		0.6	0.6
Finance leases, capitalized financing costs, investing activities		0.6	$ 0.3
Lessee, operating lease, unguaranteed residual value		15.1
Equipment
Operating Leased Assets [Line Items]
Operating lease, residual value of leased asset		2.3
Equipment | PNM
Operating Leased Assets [Line Items]
Operating lease, residual value of leased asset		0.9
Equipment | TNMP
Operating Leased Assets [Line Items]
Operating lease, residual value of leased asset		$ 1.4

Lease Commitments - Operating L

Lease Commitments - Operating Lease Balance Sheet Information (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Operating leases:
Operating lease assets, net of amortization	$ 99,017	$ 105,133
Current portion of operating lease liabilities	28,160	27,460
Long-term portion of operating lease liabilities	71,492	81,065
PNM
Operating leases:
Operating lease assets, net of amortization	91,652	97,461
Current portion of operating lease liabilities	25,868	25,130
Long-term portion of operating lease liabilities	66,657	75,941
TNMP
Operating leases:
Operating lease assets, net of amortization	6,937	7,206
Current portion of operating lease liabilities	2,185	2,193
Long-term portion of operating lease liabilities	$ 4,515	$ 4,779

Lease Commitments - Finance Lea

Lease Commitments - Finance Lease Balance Sheet Information (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financing leases:
Non-utility property	$ 25,997	$ 25,055
Accumulated depreciation	(5,528)	(4,383)
Non-utility property, net	20,469	20,672
Other current liabilities	4,641	4,470
Other deferred credits	15,616	15,972
PNM
Financing leases:
Non-utility property	12,140	11,453
Accumulated depreciation	(2,575)	(2,044)
Non-utility property, net	9,565	9,409
Other current liabilities	2,119	1,993
Other deferred credits	7,225	7,176
TNMP
Financing leases:
Non-utility property	13,535	13,299
Accumulated depreciation	(2,833)	(2,241)
Non-utility property, net	10,702	11,058
Other current liabilities	2,436	2,397
Other deferred credits	$ 8,272	$ 8,669

Lease Commitments - Schedule of

Lease Commitments - Schedule of Weighted Average Remaining Lease Terms and Discount Rates (Details)	Mar. 31, 2021
Weighted average remaining lease term (years):
Operating leases	5 years 10 months 20 days
Financing leases	4 years 8 months 1 day
Weighted average discount rate:
Operating leases	3.96%
Financing leases	2.76%
PNM
Weighted average remaining lease term (years):
Operating leases	6 years 25 days
Financing leases	4 years 8 months 12 days
Weighted average discount rate:
Operating leases	3.96%
Financing leases	2.71%
TNMP
Weighted average remaining lease term (years):
Operating leases	3 years 4 months 28 days
Financing leases	4 years 8 months 8 days
Weighted average discount rate:
Operating leases	3.94%
Financing leases	2.81%

Lease Commitments - Components

Lease Commitments - Components of Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Lease, Cost [Line Items]
Operating lease cost:	$ 7,429	$ 7,735
Amounts capitalized	(785)	(925)
Total operating lease expense	6,644	6,810
Financing lease cost:
Amortization of right-of-use assets	1,167	553
Interest on lease liabilities	139	103
Amounts capitalized	(993)	(458)
Total financing lease expense	313	198
Variable lease expense	63	32
Short-term lease expense	132	86
Total lease expense for the period	7,152	7,126
PNM
Lease, Cost [Line Items]
Operating lease cost:	6,735	6,893
Amounts capitalized	(226)	(291)
Total operating lease expense	6,509	6,602
Financing lease cost:
Amortization of right-of-use assets	532	247
Interest on lease liabilities	62	45
Amounts capitalized	(368)	(175)
Total financing lease expense	226	117
Variable lease expense	63	32
Short-term lease expense	124	85
Total lease expense for the period	6,922	6,836
TNMP
Lease, Cost [Line Items]
Operating lease cost:	653	774
Amounts capitalized	(559)	(634)
Total operating lease expense	94	140
Financing lease cost:
Amortization of right-of-use assets	613	289
Interest on lease liabilities	76	56
Amounts capitalized	(625)	(283)
Total financing lease expense	64	62
Variable lease expense	0	0
Short-term lease expense	2	1
Total lease expense for the period	$ 160	$ 203

Lease Commitments - Schedule _2

Lease Commitments - Schedule of Supplemental Cash Flows Related to Leases (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 9,401	$ 9,658
Operating cash flows from financing leases	30	27
Finance cash flows from financing leases	278	147
Non-cash information related to right-of-use assets obtained in exchange for lease obligations:
Operating leases	317	0
Financing leases	1,164	4,272
PNM
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	9,246	9,351
Operating cash flows from financing leases	21	16
Finance cash flows from financing leases	186	80
Non-cash information related to right-of-use assets obtained in exchange for lease obligations:
Operating leases	0	0
Financing leases	758	1,463
TNMP
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	97	166
Operating cash flows from financing leases	8	9
Finance cash flows from financing leases	71	51
Non-cash information related to right-of-use assets obtained in exchange for lease obligations:
Operating leases	317	0
Financing leases	$ 387	$ 2,802

Lease Commitments - Schedule _3

Lease Commitments - Schedule of Future Expected Lease Payments (Details) $ in Thousands	Mar. 31, 2021USD ($)
Financing
Remainder of 2021	$ 3,858
2022	4,995
2023	4,710
2024	3,529
2025	2,168
Later years	2,308
Total minimum lease payments	21,568
Less: Imputed interest	1,311
Lease liabilities as of March 31, 2021	20,257
Operating
Remainder of 2021	19,025
2022	28,653
2023	19,063
2024	8,897
2025	7,721
Later years	27,815
Total minimum lease payments	111,174
Less: Imputed interest	11,522
Lease liabilities as of March 31, 2021	99,652
PNM
Financing
Remainder of 2021	1,760
2022	2,296
2023	2,229
2024	1,565
2025	935
Later years	1,156
Total minimum lease payments	9,941
Less: Imputed interest	597
Lease liabilities as of March 31, 2021	9,344
Operating
Remainder of 2021	17,099
2022	26,544
2023	17,477
2024	7,915
2025	6,919
Later years	27,521
Total minimum lease payments	103,475
Less: Imputed interest	10,950
Lease liabilities as of March 31, 2021	92,525
TNMP
Financing
Remainder of 2021	2,032
2022	2,613
2023	2,431
2024	1,956
2025	1,233
Later years	1,153
Total minimum lease payments	11,418
Less: Imputed interest	710
Lease liabilities as of March 31, 2021	10,708
Operating
Remainder of 2021	1,831
2022	2,039
2023	1,548
2024	945
2025	763
Later years	76
Total minimum lease payments	7,202
Less: Imputed interest	502
Lease liabilities as of March 31, 2021	$ 6,700

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2017	Dec. 31, 2020
Income Tax Contingency [Line Items]
Accelerated refund application amount of AMT tax, CARES act			$ 5.2
Deferred tax assets, tax deferred expense, payroll taxes, CARES Act			$ 7
Deferred federal, state and local, income tax expense (benefit)	$ 24.5
Effective tax rate	12.91%
Tax benefits related to stock awards	$ 0.7
Tax benefits on merger-related costs	1.2
PNM
Income Tax Contingency [Line Items]
Deferred federal, state and local, income tax expense (benefit)	$ 15.2
Effective tax rate	15.40%
Tax benefits related to stock awards	$ 0.5
TNMP
Income Tax Contingency [Line Items]
Deferred federal, state and local, income tax expense (benefit)	$ 9.3
Effective tax rate	10.67%
Tax benefits related to stock awards	$ 0.2
NMPRC
Income Tax Contingency [Line Items]
Period of time for proposed return to customers the benefit of the reduction in federal corporate income tax rate		23 years
Period of time for proposed return to customers the benefit of the reduction in New Mexico's corporate income tax rate		3 years

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Related Party Transaction [Line Items]
Ownership percentage	50.00%
Services billings: | PNMR to PNM
Related Party Transaction [Line Items]
Amount of related party transaction	$ 26,225	$ 22,123
Services billings: | PNMR to TNMP
Related Party Transaction [Line Items]
Amount of related party transaction	10,365	8,727
Services billings: | PNM to TNMP
Related Party Transaction [Line Items]
Amount of related party transaction	118	76
Services billings: | TNMP to PNMR
Related Party Transaction [Line Items]
Amount of related party transaction	12	35
Services billings: | PNMR to NMRD
Related Party Transaction [Line Items]
Amount of related party transaction	55	76
Renewable energy purchases: | PNM from NMRD
Related Party Transaction [Line Items]
Amount of related party transaction	2,585	1,519
Interconnection billings: | PNM from NMRD
Related Party Transaction [Line Items]
Amount of related party transaction	0	220
Interconnection billings: | PNM to PNMR
Related Party Transaction [Line Items]
Amount of related party transaction	0	0
Interconnection billings: | NMRD to PNM
Related Party Transaction [Line Items]
Amount of related party transaction	1,276	0
Interest billings: | PNMR to PNM
Related Party Transaction [Line Items]
Amount of related party transaction	0	0
Interest billings: | PNMR to TNMP
Related Party Transaction [Line Items]
Amount of related party transaction	0	1
Interest billings: | PNM to PNMR
Related Party Transaction [Line Items]
Amount of related party transaction	36	81
Income tax sharing payments: | PNMR to PNM
Related Party Transaction [Line Items]
Amount of related party transaction	0	0
Income tax sharing payments: | TNMP to PNMR
Related Party Transaction [Line Items]
Amount of related party transaction	$ 0	$ 0

Equity Method Investment (Detai

Equity Method Investment (Details) $ in Thousands	1 Months Ended	3 Months Ended
	Feb. 28, 2021USD ($)	Mar. 31, 2021USD ($)MW	Mar. 31, 2020USD ($)
Business Acquisition [Line Items]
Ownership percentage		50.00%
Distributions from NMRD		$ 572	$ 0
NMRD
Business Acquisition [Line Items]
Renewable energy capacity in operating (in mw) | MW		135.1
PNMR Development
Business Acquisition [Line Items]
Ownership percentage		50.00%
PNMR Development | NMRD
Business Acquisition [Line Items]
Ownership percentage		50.00%
Contribution to construction activities		$ 0	$ 10,000
Distributions from NMRD	$ 3,000
Earnings from equity method investments, net of dividends or distributions	2,400
Proceeds from equity method investment, distribution, return of capital	$ 600
AEP OnSite Partners | NMRD
Business Acquisition [Line Items]
Ownership percentage		50.00%

Equity Method Investment - Summ

Equity Method Investment - Summarized Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Results of Operations
Revenues	$ 364,707	$ 333,622
Financial Position
Construction work in progress	282,704		$ 218,719
Assets	7,943,309	7,375,119	7,939,854
Total stockholders' equity	2,030,966		2,049,465
NMRD
Results of Operations
Revenues	2,750	1,667
Operating Expenses	2,522	1,580
Net Earnings (Loss) Attributable to PNMR	228	$ 87
Financial Position
Current assets	5,005		8,046
Construction work in progress	170,032		172,585
Non-current assets	2,133		1,900
Assets	177,170		182,531
Current liabilities	1,249		841
Non-current liabilities	383		380
Total stockholders' equity	$ 175,538		$ 181,310

Merger (Details)

Merger (Details) - Forecast - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Jun. 30, 2022	Dec. 31, 2022
Avangrid | Iberdrola, S.A.
Business Acquisition [Line Items]
Noncontrolling interest, ownership percentage by parent		81.50%
Merger Agreement
Business Acquisition [Line Items]
Business combination, cash right per common share (in dollars per share)		$ 50.30
Out-of-pocket fees and expenses reimbursement	$ 10
Merger Agreement | PNMR
Business Acquisition [Line Items]
Termination fees	130
Merger Agreement | Avangrid
Business Acquisition [Line Items]
Termination fees	$ 184