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Income Taxes (Tables) | 12 Months Ended
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Dec. 31, 2017
Income Tax Disclosure [Abstract] |
Summary of Tax Reform Adjustments | The adjustments to deferred income taxes recorded as increases in regulatory liabilities and income tax expense as a result of the enactment of the Tax Act are presented below:
|  | PNM |  | TNMP |  | Corporate and Other |  | Consolidated
|  | (In thousands)
Net increase in regulatory liabilities |  | $ | 402,501 |  |  | $ | 146,451 |  |  | $ | — |  |  | $ | 548,952 |
Net decrease in deferred income tax liabilities (deferred income tax assets) |  | 372,895 |  |  | 138,586 |  |  | (19,990 | ) |  | 491,491 |
Net deferred income tax expense |  | $ | 29,606 |  |  | $ | 7,865 |  |  | $ | 19,990 |  |  | $ | 57,461 |
Schedule of Components of Income Tax Expense (Benefit) | PNM’s income taxes (benefit) consist of the following components:
| Year Ended December 31,
| 2017 |  | 2016 |  | 2015
| (In thousands)
Current federal income tax | $ | 118 |  |  | $ | (10,290 | ) |  | $ | (7,934 | )
Current state income tax | (1,112 | ) |  | (1,907 | ) |  | (1,988 | )
Deferred federal income tax | 73,308 |  |  | 49,123 |  |  | (6,827 | )
Deferred state income tax | 9,527 |  |  | 4,969 |  |  | 5,333 |
Amortization of accumulated investment tax credits | (286 | ) |  | (973 | ) |  | (1,342 | )
Total income taxes (benefit) | $ | 81,555 |  |  | $ | 40,922 |  |  | $ | (12,758 | )
PNMR’s income taxes consist of the following components:
| Year Ended December 31,
| 2017 |  | 2016 |  | 2015
| (In thousands)
Current federal income tax | $ | — |  |  | $ | — |  |  | $ | — |
Current state income tax | (188 | ) |  | (527 | ) |  | (1,376 | )
Deferred federal income tax | 119,182 |  |  | 60,892 |  |  | 5,488 |
Deferred state income tax | 11,632 |  |  | 3,886 |  |  | 12,305 |
Amortization of accumulated investment tax credits | (286 | ) |  | (973 | ) |  | (1,342 | )
Total income taxes | $ | 130,340 |  |  | $ | 63,278 |  |  | $ | 15,075 |
TNMP’s income taxes consist of the following components:
| Year Ended December 31,
| 2017 |  | 2016 |  | 2015
| (In thousands)
Current federal income tax | $ | 2,472 |  |  | $ | 9,445 |  |  | $ | 1,603 |
Current state income tax | 1,765 |  |  | 1,729 |  |  | 1,639 |
Deferred federal income tax | 27,304 |  |  | 12,690 |  |  | 20,904 |
Deferred state income tax | (29 | ) |  | (28 | ) |  | (21 | )
Total income taxes | $ | 31,512 |  |  | $ | 23,836 |  |  | $ | 24,125 |
Schedule of Effective Income Tax Rate Reconciliation | The differences are attributable to the following factors:
| Year Ended December 31,
| 2017 |  | 2016 |  | 2015
| (In thousands)
Federal income tax at statutory rates | $ | 23,475 |  |  | $ | 22,928 |  |  | $ | 23,131 |
State income tax, net of federal benefit | 1,198 |  |  | 1,132 |  |  | 1,065 |
Federal income tax rate change | 7,865 |  |  | — |  |  | — |
Allocation of excess tax benefit related to stock compensation awards | (616 | ) |  | — |  |  | — |
Other | (410 | ) |  | (224 | ) |  | (71 | )
Total income taxes | $ | 31,512 |  |  | $ | 23,836 |  |  | $ | 24,125 |
Effective tax rate | 46.98 | % |  | 36.39 | % |  | 36.5 | %
The differences are attributable to the following factors:
| Year Ended December 31,
| 2017 |  | 2016 |  | 2015
| (In thousands)
Federal income tax (benefit) at statutory rates | $ | 59,139 |  |  | $ | 46,501 |  |  | $ | (4,579 | )
Amortization of accumulated investment tax credits | (286 | ) |  | (973 | ) |  | (1,342 | )
Flow-through of depreciation items | 1,103 |  |  | 1,185 |  |  | 1,465 |
Earnings attributable to non-controlling interest in Valencia | (5,256 | ) |  | (5,082 | ) |  | (5,218 | )
State income tax, net of federal benefit | 4,926 |  |  | 3,921 |  |  | (2,162 | )
Impairment of state net operating loss carryforwards | 627 |  |  | (213 | ) |  | 3,619 |
Allowance for equity funds used during construction | (3,032 | ) |  | (1,457 | ) |  | (3,650 | )
Reversal of deferred items related to BART at SJGS | — |  |  | — |  |  | 1,826 |
Regulatory recovery of prior year impairment of state net operating loss carryforward, net of amortization | (2,225 | ) |  | (1,877 | ) |  | — |
Federal income tax rate change | 29,606 |  |  | — |  |  | — |
Allocation of excess tax benefit related to stock compensation awards | (1,708 | ) |  | — |  |  | — |
Other | (1,339 | ) |  | (1,083 | ) |  | (2,717 | )
Total income taxes (benefit) | $ | 81,555 |  |  | $ | 40,922 |  |  | $ | (12,758 | )
Effective tax rate | 48.27 | % |  | 30.80 | % |  | 97.52 | %
PNMR’s provision for income taxes differed from the federal income tax computed at the statutory rate for each of the years shown. The differences are attributable to the following factors:
| Year Ended December 31,
| 2017 |  | 2016 |  | 2015
| (In thousands)
Federal income tax at statutory rates | $ | 79,016 |  |  | $ | 68,311 |  |  | $ | 16,154 |
Amortization of accumulated investment tax credits | (286 | ) |  | (973 | ) |  | (1,342 | )
Flow-through of depreciation items | 1,147 |  |  | 1,227 |  |  | 1,485 |
Earnings attributable to non-controlling interest in Valencia | (5,256 | ) |  | (5,082 | ) |  | (5,218 | )
State income tax, net of federal benefit | 5,398 |  |  | 4,537 |  |  | (1,781 | )
Impairment of state net operating loss carryforwards | 819 |  |  | (311 | ) |  | 5,278 |
Impairment of state production tax credits | — |  |  | — |  |  | 3,092 |
Allowance for equity funds used during construction | (3,331 | ) |  | (1,732 | ) |  | (3,650 | )
Reversal of deferred items related to BART at SJGS | — |  |  | — |  |  | 1,826 |
Impairment of charitable contribution carryforward | 909 |  |  | — |  |  | 2,042 |
Regulatory recovery of prior year impairments of state net operating loss carryforward, net of amortization | (2,225 | ) |  | (1,877 | ) |  | — |
Federal income tax rate change | 57,461 |  |  | — |  |  | — |
Excess tax benefits related to stock compensation awards | (2,324 | ) |  | — |  |  | — |
Other | (988 | ) |  | (822 | ) |  | (2,811 | )
Total income taxes | $ | 130,340 |  |  | $ | 63,278 |  |  | $ | 15,075 |
Effective tax rate | 57.73 | % |  | 32.42 | % |  | 32.66 | %
Components of Deferred Tax Assets and Liabilities | The components of PNM’s net accumulated deferred income tax liability were:
| December 31,
| 2017 |  | 2016
| (In thousands)
Deferred tax assets: |  |  |
Net operating loss | $ | 67,719 |  |  | $ | 117,922 |
Regulatory liabilities related to income taxes | 152,059 |  |  | 60,940 |
Federal tax credit carryforwards | 60,085 |  |  | 59,156 |
Shutdown of SJGS Units 2 and 3 | 2,204 |  |  | 53,434 |
Other | 23,801 |  |  | 41,700 |
Total deferred tax assets | 305,868 |  |  | 333,152 |
Deferred tax liabilities: |  |  |
Depreciation and plant related | (544,270 | ) |  | (891,578 | )
Investment tax credit | (55,731 | ) |  | (56,017 | )
Regulatory assets related to income taxes | (52,392 | ) |  | (56,577 | )
Pension | (51,774 | ) |  | (50,134 | )
Regulatory asset for shutdown of SJGS Units 2 and 3 | (31,887 | ) |  | — |
Other | (18,826 | ) |  | (27,512 | )
Total deferred tax liabilities | (754,880 | ) |  | (1,081,818 | )
Net accumulated deferred income tax liabilities | $ | (449,012 | ) |  | $ | (748,666 | )
The components of TNMP’s net accumulated deferred income tax liability at December 31, were:
| December 31,
| 2017 |  | 2016
| (In thousands)
Deferred tax assets: |  |  |
Regulatory liabilities related to income taxes | $ | 43,103 |  |  | $ | 3,718 |
Other | 3,762 |  |  | 6,016 |
Total deferred tax assets | 46,865 |  |  | 9,734 |
Deferred tax liabilities: |  |  |
Depreciation and plant related | (135,647 | ) |  | (201,017 | )
CTC | (5,670 | ) |  | (12,715 | )
Regulatory assets related to income taxes | (9,564 | ) |  | (9,800 | )
Loss on reacquired debt | (6,890 | ) |  | (11,937 | )
Pension | (4,296 | ) |  | (7,153 | )
AMS | (7,707 | ) |  | (8,928 | )
Other | (3,506 | ) |  | (3,969 | )
Total deferred tax liabilities | (173,280 | ) |  | (255,519 | )
Net accumulated deferred income tax liabilities | $ | (126,415 | ) |  | $ | (245,785 | )
The components of PNMR’s net accumulated deferred income tax liability were:
| December 31,
| 2017 |  | 2016
| (In thousands)
Deferred tax assets: |  |  |
Net operating loss | $ | 98,301 |  |  | $ | 160,901 |
Regulatory liabilities related to income taxes | 189,501 |  |  | 64,657 |
Federal tax credit carryforwards | 71,849 |  |  | 78,675 |
Shutdown of SJGS Units 2 and 3 | 2,204 |  |  | 53,434 |
Other | 45,656 |  |  | 75,805 |
Total deferred tax assets | 407,511 |  |  | 433,472 |
Deferred tax liabilities: |  |  |
Depreciation and plant related | (690,909 | ) |  | (1,102,458 | )
Investment tax credit | (55,731 | ) |  | (56,017 | )
Regulatory assets related to income taxes | (61,956 | ) |  | (66,378 | )
CTC | (5,670 | ) |  | (12,715 | )
Pension | (56,070 | ) |  | (57,287 | )
Regulatory asset for shutdown of SJGS Units 2 and 3 | (31,887 | ) |  | — |
Other | (52,498 | ) |  | (79,267 | )
Total deferred tax liabilities | (954,721 | ) |  | (1,374,122 | )
Net accumulated deferred income tax liabilities | $ | (547,210 | ) |  | $ | (940,650 | )
Reconciliation of Accumulated Deferred Income Tax Liability to Deferred Income Tax Benefit | The following table reconciles the change in TNMP’s net accumulated deferred income tax liability to the deferred income tax benefit included in the Consolidated Statement of Earnings:
| Year Ended
| December 31, 2017
| (In thousands)
Net change in deferred income tax liability per above table | $ | (119,370 | )
Change in tax effects of income tax related regulatory assets and liabilities | (112 | )
Federal income tax rate change | 146,451 |
Other | 306 |
Deferred income taxes | $ | 27,275 |
The following table reconciles the change in PNM’s net accumulated deferred income tax liability to the deferred income tax benefit included in the Consolidated Statement of Earnings:
| Year Ended
| December 31, 2017
| (In thousands)
Net change in deferred income tax liability per above table | $ | (299,654 | )
Change in tax effects of income tax related regulatory assets and liabilities | (16,332 | )
Tax effect of mark-to-market adjustments | (4,110 | )
Tax effect of excess pension liability | (3,421 | )
Adjustment for uncertain income tax positions | 2,614 |
Reclassification of unrecognized tax benefits | (2,614 | )
Regulatory recovery of prior year impairment of state net operating loss carryforward, net of amortization | (2,225 | )
Federal income tax rate change | 402,501 |
Allocation of cumulative effect adjustment for excess tax benefit related to stock compensation awards | 7,770 |
Other | (1,980 | )
Deferred income taxes | $ | 82,549 |
The following table reconciles the change in PNMR’s net accumulated deferred income tax liability to the deferred income tax benefit included in the Consolidated Statement of Earnings:
| Year Ended
| December 31, 2017
| (In thousands)
Net change in deferred income tax liability per above table | $ | (393,440 | )
Change in tax effects of income tax related regulatory assets and liabilities | (16,444 | )
Tax effect of mark-to-market adjustments | (4,724 | )
Tax effect of excess pension liability | (3,421 | )
Adjustment for uncertain income tax positions | 2,677 |
Reclassification of unrecognized tax benefits | (2,677 | )
Regulatory recovery of prior year impairments of state net operating loss carryforward, net of amortization | (2,225 | )
Federal income tax rate change | 548,952 |
Cumulative effect adjustment for excess tax benefit related to stock compensation awards | 10,382 |
Alternative minimum tax carryforward reclassified to receivable | (8,336 | )
Other | (216 | )
Deferred income taxes | $ | 130,528 |
Reconciliation of Unrecognized Tax Benefits (Expenses) | A reconciliation of unrecognized tax benefits (expenses) is as follows:
| PNMR |  | PNM |  | TNMP
| (In thousands)
Balance at December 31, 2014 | $ | 15,031 |  |  | $ | 12,228 |  |  | $ | — |
Additions based on tax positions related to 2015 | 1,214 |  |  | 1,214 |  |  | — |
Additions (reductions) for tax positions of prior years | (9,790 | ) |  | (9,790 | ) |  | — |
Settlement payments | — |  |  | — |  |  | — |
Balance at December 31, 2015 | 6,455 |  |  | 3,652 |  |  | — |
Additions based on tax positions related to 2016 | 242 |  |  | 242 |  |  | — |
Additions (reductions) for tax positions of prior years | 55 |  |  | 55 |  |  | — |
Settlement payments | — |  |  | — |  |  | — |
Balance at December 31, 2016 | 6,752 |  |  | 3,949 |  |  | — |
Additions based on tax positions related to 2017 | 262 |  |  | 262 |  |  | — |
Additions (reductions) for tax positions of prior years | 2,415 |  |  | 2,352 |  |  | 63 |
Settlement payments | — |  |  | — |  |  | — |
Balance at December 31, 2017 | $ | 9,429 |  |  | $ | 6,563 |  |  | $ | 63 |
Interest Income (Expense) Related to Income Taxes | Interest income (expense) related to income taxes was as follows:
| PNMR |  | PNM |  | TNMP
| (In thousands)
2017 | $ | — |  |  | $ | — |  |  | $ | — |
2016 | $ | 4,398 |  |  | $ | 3,625 |  |  | $ | 345 |
2015 | $ | — |  |  | $ | — |  |  | $ | — |
Deferred Income Taxes, Increase (Decrease) In Regulatory Liability and Income Tax Expense | Adjustments to deferred income taxes recorded as increases (decreases) in the regulatory liability and income tax expense are as follows:
| PNMR |  | PNM |  | TNMP
| (In thousands)
December 31, 2017: |  |  |  |  |
Regulatory liability | $ | (10,109 | ) |  | $ | (10,109 | ) |  | $ | — |
Income tax expense | $ | (1,259 | ) |  | $ | (1,179 | ) |  | $ | — |
December 31, 2016: |  |  |  |  |
Regulatory liability | $ | (7,132 | ) |  | $ | (7,132 | ) |  | $ | — |
Income tax expense | $ | 712 |  |  | $ | 804 |  |  | $ | — |
December 31, 2015: |  |  |  |  |
Regulatory liability | $ | (1,903 | ) |  | $ | (1,903 | ) |  | $ | — |
Income tax expense | $ | (674 | ) |  | $ | (470 | ) |  | $ | — |
Tax Carryforward, Impairments, net of Federal Tax Benefit | The impairments, net of federal tax benefit, for 2015 through 2017 are as follows:
| PNMR |  | PNM |  | TNMP
| (In thousands)
December 31, 2017: |  |  |  |  |
State tax credit carryforwards | $ | — |  |  | $ | — |  |  | $ | — |
State net operating loss carryforwards | $ | 819 |  |  | $ | 627 |  |  | $ | — |
Charitable contribution carryforwards | $ | 909 |  |  | $ | — |  |  | $ | — |
December 31, 2016: |  |  |  |  |
State tax credit carryforwards | $ | — |  |  | $ | — |  |  | $ | — |
State net operating loss carryforwards | $ | (311 | ) |  | $ | (213 | ) |  | $ | — |
Charitable contribution carryforwards | $ | — |  |  | $ | — |  |  | $ | — |
December 31, 2015: |  |  |  |  |
State tax credit carryforwards | $ | 3,092 |  |  | $ | — |  |  | $ | — |
State net operating loss carryforwards | $ | 5,278 |  |  | $ | 3,619 |  |  | $ | — |
Charitable contribution carryforwards | $ | 2,042 |  |  | $ | — |  |  | $ | — |
Summary of Tax Credit Carryforwards | The reserve balances, after reflecting expiration of carryforwards under applicable tax laws, at December 31, 2017 and 2016 are as follows:
| PNMR |  | PNM |  | TNMP
| (In thousands)
December 31, 2017: |  |  |  |  |
State tax credit carryforwards | $ | 2,487 |  |  | $ | — |  |  | $ | — |
State net operating loss carryforwards | $ | 1,131 |  |  | $ | 839 |  |  | $ | — |
Charitable contribution carryforwards | $ | 952 |  |  | $ | — |  |  | $ | — |
December 31, 2016: |  |  |  |  |
State tax credit carryforwards | $ | 3,986 |  |  | $ | — |  |  | $ | — |
State net operating loss carryforwards | $ | 361 |  |  | $ | 248 |  |  | $ | — |
Charitable contribution carryforwards | $ | 659 |  |  | $ | — |  |  | $ | — |

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