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Fair Value of Derivative and Other Financial Instruments (Tables) | 12 Months Ended
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Dec. 31, 2018
Fair Value of Derivative and Other Financial Instruments [Abstract] |
Schedule of Commodity Derivatives | PNM’s commodity derivative instruments that are recorded at fair value, all of which are accounted for as economic hedges, are summarized as follows:
| Economic Hedges
| December 31,
| 2018 |  | 2017
| (In thousands)
Current assets | $ | 1,083 |  |  | $ | 1,088 |
Deferred charges | 2,511 |  |  | 3,556 |
| 3,594 |  |  | 4,644 |
Current liabilities | (1,177 | ) |  | (1,182 | )
Long-term liabilities | (2,511 | ) |  | (3,556 | )
| (3,688 | ) |  | (4,738 | )
Net | $ | (94 | ) |  | $ | (94 | )
Summary of the Effect of Mark-to-Market Commodity Derivative Instruments on Earnings | The following table presents the effect of mark-to-market commodity derivative instruments on PNM’s earnings, excluding income tax effects. Commodity derivatives had no impact on OCI for the periods presented.
| Economic Hedges
| Year Ended December 31,
| 2018 |  | 2017 |  | 2016
| (In thousands)
Electric operating revenues | $ | (50 | ) |  | $ | 5,151 |  |  | $ | (53 | )
Cost of energy | (52 | ) |  | (5,386 | ) |  | (1,208 | )
Total gain (loss) | $ | (102 | ) |  | $ | (235 | ) |  | $ | (1,261 | )
Schedule of Net Buy (Sell) Volume Positions | The table below presents PNM’s net buy (sell) volume positions:
| Economic Hedges
| MMBTU |  | MWh
December 31, 2018 | 100,000 |  |  | — |
December 31, 2017 | 100,000 |  |  | — |
Schedule of Fair Value and Unrealized Gains of Available-for-sale Securities | In January 2016, the FASB issued Accounting Standards Update 2016-01 – Financial Instruments (Subtopic 825-10), which makes targeted improvements to GAAP regarding financial instruments. ASU 2016-01 eliminates the requirement to classify investments in equity securities with readily determinable fair values into trading or available-for-sale categories and requires those equity securities to be measured at fair value with changes in fair value recognized in net income rather than in OCI. Under ASU 2016-01, the accounting for available-for-sale debt securities remains essentially unchanged. The accounting required by ASU 2016-01 is to be applied prospectively with a cumulative effect adjustment recorded as of the beginning of the year of adoption. ASU 2016-01 also revises certain presentation and disclosure requirements. Accordingly, the following information for 2018 is presented under ASU 2016-01 and the information for 2017 is presented under prior GAAP. Prior to 2018, PNM classified all debt and equity investments held in the NDT and coal mine reclamation trusts as available-for-sale securities. Unrealized losses on these securities were recorded immediately through earnings and unrealized gains were recorded in AOCI until the securities were sold. On January 1, 2018, PNM recorded an after-tax cumulative effect adjustment of $11.2 million to reclassify unrealized holding gains on equity securities held in the NDT and coal mine reclamation trusts from AOCI to retained earnings on the Consolidated Balance Sheets. After January 1, 2018, all gains and losses resulting from sales and changes in the fair value of equity securities are recognized in earnings. Gains and losses recognized on the Consolidated Statements of Earnings related to investment securities in the NDT and reclamation trusts are presented in the following table.
|  | Year Ended December 31, 2018
|  | (In thousands)
Equity securities: |  |
Net gains from equity securities sold |  | $ | 4,864 |
Net (losses) from equity securities still held |  | (10,523 | )
Total net (losses) on equity securities |  | (5,659 | )
Available-for-sale debt securities: |  |
Net (losses) on debt securities |  | (11,517 | )
Net (losses) on investment securities |  | $ | (17,176 | )
Schedule of Realized Gain (Loss) | Gains and losses recognized on the Consolidated Statements of Earnings related to investment securities in the NDT and reclamation trusts are presented in the following table.
|  | Year Ended December 31, 2018
|  | (In thousands)
Equity securities: |  |
Net gains from equity securities sold |  | $ | 4,864 |
Net (losses) from equity securities still held |  | (10,523 | )
Total net (losses) on equity securities |  | (5,659 | )
Available-for-sale debt securities: |  |
Net (losses) on debt securities |  | (11,517 | )
Net (losses) on investment securities |  | $ | (17,176 | )
Gross realized losses shown below exclude the (increase)/decrease in realized impairment losses of $(9.4) million, $3.3 million, and $(1.2) million for the years ended December 31, 2018, 2017 and 2016.
| Year Ended December 31,
| 2018 |  | 2017 |  | 2016
| (In thousands)
Proceeds from sales | $ | 984,533 |  |  | $ | 637,492 |  |  | $ | 522,601 |
Gross realized gains | $ | 19,358 |  |  | $ | 36,896 |  |  | $ | 46,116 |
Gross realized (losses) | $ | (16,624 | ) |  | $ | (12,993 | ) |  | $ | (25,430 | )
Investments Classified by Contractual Maturity Date | At December 31, 2018, the available-for-sale debt securities held by PNM, had the following final maturities:
| Fair Value
| (In thousands)
Within 1 year | $ | 12,488 |
After 1 year through 5 years | 63,600 |
After 5 years through 10 years | 60,344 |
After 10 years through 15 years | 9,984 |
After 15 years through 20 years | 10,904 |
After 20 years | 48,418 |
| $ | 205,738 |
Schedule of Instruments Presented by Level of Hierarchy | Items recorded at fair value by PNM on the Consolidated Balance Sheets are presented below by level of the fair value hierarchy along with gross unrealized gains on investments in available-for-sale securities. Under ASU 2016-01, PNM does not classify its investments in equity instruments as available-for-sale securities beginning January 1, 2018.
|  |  | GAAP Fair Value Hierarchy |  |
| Total |  | Quoted Prices in Active Markets for Identical Assets (Level 1) |  | Significant Other Observable Inputs (Level 2) |  | Significant Unobservable Inputs (Level 3) |  | Unrealized Gains
| (In thousands)
December 31, 2018 |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | 11,472 |  |  | $ | 11,472 |  |  | $ | — |  |  | $ | — |  |  |
Equity securities: |  |  |  |  |  |  |  |  |
Corporate stocks, common | 32,997 |  |  | 32,997 |  |  | — |  |  | — |  |  |
Corporate stocks, preferred | 7,258 |  |  | 1,654 |  |  | 5,604 |  |  | — |  |  |
Mutual funds and other | 70,777 |  |  | 70,777 |  |  | — |  |  | — |  |  |
Available-for-sale debt securities: |  |  |  |  |  |  |  |  |
U.S. Government | 29,503 |  |  | 18,662 |  |  | 10,841 |  |  | — |  |  | $ | 1,098 |
International Government | 8,435 |  |  | — |  |  | 8,435 |  |  | — |  |  | 90 |
Municipals | 53,642 |  |  | — |  |  | 53,642 |  |  | — |  |  | 489 |
Corporate and other | 114,158 |  |  | 588 |  |  | 111,414 |  |  | 2,156 |  |  | 923 |
| $ | 328,242 |  |  | $ | 136,150 |  |  | $ | 189,936 |  |  | $ | 2,156 |  |  | $ | 2,600 |
Commodity derivative assets | $ | 3,594 |  |  | $ | — |  |  | $ | 3,594 |  |  | $ | — |  |  |
Commodity derivative liabilities | (3,688 | ) |  | — |  |  | (3,688 | ) |  | — |  |  |
Net | $ | (94 | ) |  | $ | — |  |  | $ | (94 | ) |  | $ | — |  |  |
December 31, 2017 |  |  |  |  |  |  |
Available-for-sale securities |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | 52,636 |  |  | $ | 52,636 |  |  | $ | — |  |  | $ | — |  |  |
Equity securities: |  |  |  |  |  |  |  |  |
Domestic value | 40,032 |  |  | 40,032 |  |  | — |  |  | — |  |  | $ | 4,011 |
Domestic growth | 35,456 |  |  | 35,456 |  |  | — |  |  | — |  |  | 3,995 |
International and other | 45,867 |  |  | 42,332 |  |  | 3,535 |  |  | — |  |  | 6,810 |
Fixed income securities: |  |  |  |  |  |  |  |  |
U.S. Government | 34,317 |  |  | 33,645 |  |  | 672 |  |  | — |  |  | 273 |
Municipals | 48,076 |  |  | — |  |  | 48,076 |  |  | — |  |  | 1,225 |
Corporate and other | 67,140 |  |  | — |  |  | 67,140 |  |  | — |  |  | 1,714 |
| $ | 323,524 |  |  | $ | 204,101 |  |  | $ | 119,423 |  |  | $ | — |  |  | $ | 18,028 |
Commodity derivative assets | $ | 4,644 |  |  | $ | — |  |  | $ | 4,644 |  |  | $ | — |  |  |
Commodity derivative liabilities | (4,738 | ) |  | — |  |  | (4,738 | ) |  | — |  |  |
Net | $ | (94 | ) |  | $ | — |  |  | $ | (94 | ) |  | $ | — |  |  |
Summary of Carrying Amounts and Fair Value of Instruments | The carrying amounts and fair values of investments in the Westmoreland Loan, other investments, and long-term debt, which are not recorded at fair value on the Consolidated Balance Sheets are presented below:
|  |  |  |  | GAAP Fair Value Hierarchy
| Carrying Amount |  | Fair Value |  | Quoted Prices in Active Markets for Identical Assets (Level 1) |  | Significant Other Observable Inputs (Level 2) |  | Significant Unobservable Inputs (Level 3)
December 31, 2018 | (In thousands)
PNMR |  |  |  |  |  |  |  |  |
Long-term debt | $ | 2,670,111 |  |  | $ | 2,703,810 |  |  | $ | — |  |  | $ | 2,703,810 |  |  | $ | — |
Other investments | $ | 297 |  |  | $ | 297 |  |  | $ | 297 |  |  | $ | — |  |  | $ | — |
PNM |  |  |  |  |  |  |  |  |
Long-term debt | $ | 1,656,490 |  |  | $ | 1,668,736 |  |  | $ | — |  |  | $ | 1,668,736 |  |  | $ | — |
Other investments | $ | 91 |  |  | $ | 91 |  |  | $ | 91 |  |  | $ | — |  |  | $ | — |
TNMP |  |  |  |  |  |  |  |  |
Long-term debt | $ | 575,398 |  |  | $ | 597,236 |  |  | $ | — |  |  | $ | 597,236 |  |  | $ | — |
Other investments | $ | 206 |  |  | $ | 206 |  |  | $ | 206 |  |  | $ | — |  |  | $ | — |
December 31, 2017 |  |  |  |  |  |  |  |  |
PNMR |  |  |  |  |  |  |  |  |
Long-term debt | $ | 2,437,645 |  |  | $ | 2,554,836 |  |  | $ | — |  |  | $ | 2,554,836 |  |  | $ | — |
Westmoreland Loan | $ | 56,640 |  |  | $ | 66,588 |  |  | $ | — |  |  | $ | — |  |  | $ | 66,588 |
Other investments | $ | 503 |  |  | $ | 503 |  |  | $ | 503 |  |  | $ | — |  |  | $ | — |
PNM |  |  |  |  |  |  |  |  |
Long-term debt | $ | 1,657,910 |  |  | $ | 1,727,135 |  |  | $ | — |  |  | $ | 1,727,135 |  |  | $ | — |
Other investments | $ | 283 |  |  | $ | 283 |  |  | $ | 283 |  |  | $ | — |  |  | $ | — |
TNMP |  |  |  |  |  |  |  |  |
Long-term debt | $ | 480,620 |  |  | $ | 527,563 |  |  | $ | — |  |  | $ | 527,563 |  |  | $ | — |
Other investments | $ | 220 |  |  | $ | 220 |  |  | $ | 220 |  |  | $ | — |  |  | $ | — |
Schedule of Investments Held by the Employee Benefit Plans | The fair values of investments held by the employee benefit plans are as follows:
|  |  | GAAP Fair Value Hierarchy
| Total |  | Quoted Prices in Active Markets for Identical Assets (Level 1) |  | Significant Other Observable Inputs (Level 2) |  | Significant Unobservable Inputs (Level 3)
December 31, 2018 |  |  | (In thousands) |  |
PNM Pension Plan |  |  |  |  |  |  |
Participation in PNMR Master Trust Investments: |  |  |  |  |  |  |
Investments categorized within fair value hierarchy | $ | 412,790 |  |  | $ | 139,673 |  |  | $ | 272,829 |  |  | $ | 288 |
Uncategorized investments | 76,874 |  |  |  |  |  |  |
Total Master Trust Investments | $ | 489,664 |  |  |  |  |  |  |
TNMP Pension Plan |  |  |  |  |  |  |
Participation in PNMR Master Trust Investments: |  |  |  |  |  |  |
Investments categorized within fair value hierarchy | $ | 45,283 |  |  | $ | 15,149 |  |  | $ | 30,101 |  |  | $ | 33 |
Uncategorized investments | 9,378 |  |  |  |  |  |  |
Total Master Trust Investments | $ | 54,661 |  |  |  |  |  |  |
PNM OPEB Plan |  |  |  |  |  |  |
Cash and cash equivalents | $ | 190 |  |  | $ | 190 |  |  | $ | — |  |  | $ | — |
Equity securities: |  |  |  |  |  |  |
Mutual funds | 69,513 |  |  | 32,325 |  |  | 37,188 |  |  | — |
| $ | 69,703 |  |  | $ | 32,515 |  |  | $ | 37,188 |  |  | $ | — |
TNMP OPEB Plan |  |  |  |  |  |  |
Cash and cash equivalents | $ | 66 |  |  | $ | 66 |  |  | $ | — |  |  | $ | — |
Equity securities: |  |  |  |  |  |  |
Mutual funds | 8,725 |  |  | 3,723 |  |  | 5,002 |  |  | — |
| $ | 8,791 |  |  | $ | 3,789 |  |  | $ | 5,002 |  |  | $ | — |
|  |  | GAAP Fair Value Hierarchy
| Total |  | Quoted Prices in Active Markets for Identical Assets (Level 1) |  | Significant Other Observable Inputs (Level 2) |  | Significant Unobservable Inputs (Level 3)
December 31, 2017 | (In thousands)
PNM Pension Plan |  |  |  |  |  |  |
Participation in PNMR Master Trust Investments: |  |  |  |  |  |  |
Investments categorized within fair value hierarchy | $ | 487,498 |  |  | $ | 140,218 |  |  | $ | 347,089 |  |  | $ | 191 |
Uncategorized investments | 74,768 |  |  |  |  |  |  |
Total Master Trust Investments | $ | 562,266 |  |  |  |  |  |  |
TNMP Pension Plan |  |  |  |  |  |  |
Participation in PNMR Master Trust Investments: |  |  |  |  |  |  |
Investments categorized within fair value hierarchy | $ | 53,273 |  |  | $ | 15,244 |  |  | $ | 38,008 |  |  | $ | 21 |
Uncategorized investments | 10,260 |  |  |  |  |  |  |
Total Master Trust Investments | $ | 63,533 |  |  |  |  |  |  |
PNM OPEB Plan |  |  |  |  |  |  |
Cash and cash equivalents | $ | 437 |  |  | $ | 437 |  |  | $ | — |  |  | $ | — |
Equity securities: |  |  |  |  |  |  |
International funds | 10,636 |  |  | — |  |  | 10,636 |  |  | — |
Domestic value | 10,816 |  |  | 10,816 |  |  | — |  |  | — |
Domestic growth | 6,710 |  |  | 6,710 |  |  | — |  |  | — |
Other funds | 31,660 |  |  | — |  |  | 31,660 |  |  | — |
Fixed income securities: |  |  |  |  |  |  |
Mutual funds | 20,918 |  |  | 20,918 |  |  | — |  |  | — |
| $ | 81,177 |  |  | $ | 38,881 |  |  | $ | 42,296 |  |  | $ | — |
TNMP OPEB Plan |  |  |  |  |  |  |
Cash and cash equivalents | $ | 149 |  |  | $ | 149 |  |  | $ | — |  |  | $ | — |
Equity securities: |  |  |  |  |  |  |
International funds | 1,597 |  |  | — |  |  | 1,597 |  |  | — |
Domestic value | 293 |  |  | 293 |  |  | — |  |  | — |
Domestic growth | 1,410 |  |  | 1,410 |  |  | — |  |  | — |
Other funds | 4,011 |  |  | — |  |  | 4,011 |  |  | — |
Fixed income securities: |  |  |  |  |  |  |
Mutual funds | 2,685 |  |  | 2,685 |  |  | — |  |  | — |
| $ | 10,145 |  |  | $ | 4,537 |  |  | $ | 5,608 |  |  | $ | — |
The fair values of investments in the PNMR Master Trust are as follows:
|  |  | GAAP Fair Value Hierarchy
| Total |  | Quoted Prices in Active Markets for Identical Assets (Level 1) |  | Significant Other Observable Inputs (Level 2) |  | Significant Unobservable Inputs (Level 3)
December 31, 2018 | (In thousands)
PNMR Master Trust |  |  |  |  |  |  |
Cash and cash equivalents | $ | 20,120 |  |  | $ | 20,120 |  |  | $ | — |  |  | $ | — |
Equity securities: |  |  |  |  |  |  |
Corporate stocks, common | 54,270 |  |  | 54,270 |  |  | — |  |  | — |
Corporate stocks, preferred | 874 |  |  | — |  |  | 874 |  |  | — |
Mutual funds and other | 143,517 |  |  | — |  |  | 143,517 |  |  | — |
| — |  |  | — |  |  | — |  |  | — |
Fixed income securities: |  |  |  |  |  |  |
U.S. government | 84,459 |  |  | 80,482 |  |  | 3,977 |  |  | — |
International government | 5,721 |  |  | — |  |  | 5,721 |  |  | — |
Municipals | 9,558 |  |  | — |  |  | 9,558 |  |  | — |
Corporate and other | 139,554 |  |  | (50 | ) |  | 139,283 |  |  | 321 |
Total investments categorized within fair value hierarchy | 458,073 |  |  | $ | 154,822 |  |  | $ | 302,930 |  |  | $ | 321 |
Uncategorized investments: |  |  |  |  |  |  |
Private equity funds | 18,021 |  |  |  |  |  |  |
Hedge funds | 45,589 |  |  |  |  |  |  |
Real estate funds | 22,642 |  |  |  |  |  |  |
| $ | 544,325 |  |  |  |  |  |  |
December 31, 2017 |
PNMR Master Trust |  |  |  |  |  |  |
Cash and cash equivalents | $ | 7,697 |  |  | $ | 7,697 |  |  | $ | — |  |  | $ | — |
Equity securities: |  |  |  |  |  |  |
International | 42,048 |  |  | — |  |  | 42,048 |  |  | — |
Domestic value | 37,026 |  |  | 37,026 |  |  | — |  |  | — |
Domestic growth | 19,136 |  |  | 19,136 |  |  | — |  |  | — |
Other funds | 25,099 |  |  | — |  |  | 25,099 |  |  | — |
Fixed income securities: |  |  |  |  |  |  |
Corporate | 215,535 |  |  | — |  |  | 215,323 |  |  | 212 |
U.S. Government | 117,572 |  |  | 91,603 |  |  | 25,969 |  |  | — |
Municipals | 11,438 |  |  | — |  |  | 11,438 |  |  | — |
Other funds | 65,220 |  |  | — |  |  | 65,220 |  |  | — |
Total investments categorized within fair value hierarchy | 540,771 |  |  | $ | 155,462 |  |  | $ | 385,097 |  |  | $ | 212 |
Uncategorized investments: |  |  |  |  |  |  |
Private equity funds | 22,281 |  |  |  |  |  |  |
Hedge funds | 45,615 |  |  |  |  |  |  |
Real estate funds | 17,132 |  |  |  |  |  |  |
| $ | 625,799 |  |  |  |  |  |  |
Summary of Level 3 Measurements | A reconciliation of the changes in Level 3 fair value measurements is as follows:
| Fixed Income - Corporate
PNMR Master Trust | PNM Pension |  | TNMP Pension |  | Total Master Trust
| (In thousands)
Balance at December 31, 2016 | $ | 352 |  |  | $ | 38 |  |  | $ | 390 |
Actual return on assets sold during the period | 1 |  |  | — |  |  | 1 |
Actual return on assets still held at period end | (7 | ) |  | (1 | ) |  | (8 | )
Purchases | 92 |  |  | 10 |  |  | 102 |
Sales | (247 | ) |  | (26 | ) |  | (273 | )
Balance at December 31, 2017 | 191 |  |  | 21 |  |  | 212 |
Actual return on assets sold during the period | (7 | ) |  | (1 | ) |  | (8 | )
Actual return on assets still held at period end | (1 | ) |  | — |  |  | (1 | )
Purchases | 192 |  |  | 23 |  |  | 215 |
Sales | (87 | ) |  | (10 | ) |  | (97 | )
Balance at December 31, 2018 | $ | 288 |  |  | $ | 33 |  |  | $ | 321 |
The following table presents information about the PBO, fair value of plan assets, and funded status of the plans:
| PNM |  | TNMP
| Year Ended December 31, |  | Year Ended December 31,
| 2018 |  | 2017 |  | 2018 |  | 2017
| (In thousands)
PBO at beginning of year | $ | 623,983 |  |  | $ | 621,751 |  |  | $ | 68,423 |  |  | $ | 67,061 |
Service cost | — |  |  | — |  |  | — |  |  | — |
Interest cost | 24,270 |  |  | 26,908 |  |  | 2,625 |  |  | 2,887 |
Actuarial (gain) loss | (41,025 | ) |  | 26,298 |  |  | (5,216 | ) |  | 3,050 |
Benefits paid | (42,970 | ) |  | (50,974 | ) |  | (5,245 | ) |  | (4,575 | )
PBO at end of year | 564,258 |  |  | 623,983 |  |  | 60,587 |  |  | 68,423 |
Fair value of plan assets at beginning of year | 562,016 |  |  | 543,601 |  |  | 63,499 |  |  | 60,624 |
Actual return on plan assets | (29,068 | ) |  | 69,389 |  |  | (3,180 | ) |  | 7,450 |
Employer contributions | — |  |  | — |  |  | — |  |  | — |
Benefits paid | (42,970 | ) |  | (50,974 | ) |  | (5,245 | ) |  | (4,575 | )
Fair value of plan assets at end of year | 489,978 |  |  | 562,016 |  |  | 55,074 |  |  | 63,499 |
Funded status – asset (liability) for pension benefits | $ | (74,280 | ) |  | $ | (61,967 | ) |  | $ | (5,513 | ) |  | $ | (4,924 | )
The following table presents information about the APBO, the fair value of plan assets, and the funded status of the plans:
| PNM |  | TNMP
| Year Ended December 31, |  | Year Ended December 31,
| 2018 |  | 2017 |  | 2018 |  | 2017
| (In thousands)
APBO at beginning of year | $ | 89,897 |  |  | $ | 94,269 |  |  | $ | 12,279 |  |  | $ | 12,830 |
Service cost | 83 |  |  | 96 |  |  | 134 |  |  | 143 |
Interest cost | 3,439 |  |  | 4,025 |  |  | 477 |  |  | 556 |
Participant contributions | 2,390 |  |  | 3,069 |  |  | 174 |  |  | 379 |
Actuarial (gain) loss | (12,206 | ) |  | (1,601 | ) |  | (2,213 | ) |  | (381 | )
Benefits paid | (8,298 | ) |  | (9,961 | ) |  | (787 | ) |  | (1,248 | )
APBO at end of year | 75,305 |  |  | 89,897 |  |  | 10,064 |  |  | 12,279 |
Fair value of plan assets at beginning of year | 80,356 |  |  | 72,694 |  |  | 10,002 |  |  | 8,544 |
Actual return on plan assets | (7,669 | ) |  | 14,222 |  |  | (988 | ) |  | 1,642 |
Employer contributions | 2,924 |  |  | 332 |  |  | 343 |  |  | 685 |
Participant contributions | 2,390 |  |  | 3,069 |  |  | 174 |  |  | 379 |
Benefits paid | (8,298 | ) |  | (9,961 | ) |  | (787 | ) |  | (1,248 | )
Fair value of plan assets at end of year | 69,703 |  |  | 80,356 |  |  | 8,744 |  |  | 10,002 |
Funded status – asset (liability) | $ | (5,602 | ) |  | $ | (9,541 | ) |  | $ | (1,320 | ) |  | $ | (2,277 | )

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