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Pension and Other Postretirement Benefit Plans (Details) - USD ($) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016
PNM | Pension Plan |  |  |  |
Components of Net Periodic Benefit Cost |  |  |  |
Service cost | $ 0 | $ 0 | $ 0 | $ 0
Interest cost | 6,727,000 | 7,577,000 | 13,454,000 | 15,154,000
Expected return on plan assets | (8,451,000) | (8,854,000) | (16,901,000) | (17,708,000)
Amortization of net (gain) loss | 4,001,000 | 3,455,000 | 8,003,000 | 6,910,000
Amortization of prior service cost | (241,000) | (241,000) | (483,000) | (483,000)
Net Periodic Benefit Cost | 2,036,000 | 1,937,000 | 4,073,000 | 3,873,000
Contributions by employer | 0 | 0 | 0 | 0
Total expected employer contributions for future fiscal years | 0 |  | $ 0 |
PNM | Pension Plan | Minimum |  |  |  |
Components of Net Periodic Benefit Cost |  |  |  |
Assumptions used calculating net periodic benefit cost, discount rate |  |  | 4.10% |
PNM | Pension Plan | Maximum |  |  |  |
Components of Net Periodic Benefit Cost |  |  |  |
Assumptions used calculating net periodic benefit cost, discount rate |  |  | 4.90% |
PNM | OPEB Plan |  |  |  |
Components of Net Periodic Benefit Cost |  |  |  |
Service cost | 24,000 | 35,000 | $ 48,000 | 70,000
Interest cost | 1,006,000 | 1,087,000 | 2,013,000 | 2,173,000
Expected return on plan assets | (1,308,000) | (1,371,000) | (2,615,000) | (2,742,000)
Amortization of net (gain) loss | 921,000 | 286,000 | 1,841,000 | 572,000
Amortization of prior service cost | (416,000) | (7,000) | (832,000) | (15,000)
Net Periodic Benefit Cost | 227,000 | 30,000 | 455,000 | 58,000
Contributions by employer | 0 | 800,000 | 0 | 1,600,000
Total expected employer contributions for future fiscal years | 0 |  | 0 |
PNM | Executive Retirement Program |  |  |  |
Components of Net Periodic Benefit Cost |  |  |  |
Service cost | 0 | 0 | 0 | 0
Interest cost | 174,000 | 203,000 | 349,000 | 406,000
Expected return on plan assets | 0 | 0 | 0 | 0
Amortization of net (gain) loss | 78,000 | 64,000 | 157,000 | 128,000
Amortization of prior service cost | 0 | 0 | 0 | 0
Net Periodic Benefit Cost | 252,000 | 267,000 | 506,000 | 534,000
Contributions by employer | 400,000 | 400,000 | 900,000 | 900,000
Total expected employer contributions for future fiscal years | 5,800,000 |  | 5,800,000 |
Total expected employer contributions for fiscal year | 1,500,000 |  | 1,500,000 |
Texas-New Mexico Power Company | Pension Plan |  |  |  |
Components of Net Periodic Benefit Cost |  |  |  |
Service cost | 0 | 0 | 0 | 0
Interest cost | 722,000 | 826,000 | 1,443,000 | 1,652,000
Expected return on plan assets | (945,000) | (986,000) | (1,889,000) | (1,971,000)
Amortization of net (gain) loss | 231,000 | 175,000 | 461,000 | 350,000
Amortization of prior service cost | 0 | 0 | 0 | 0
Net Periodic Benefit Cost | 8,000 | 15,000 | 15,000 | 31,000
Contributions by employer | 0 | 0 | 0 | 0
Total expected employer contributions for future fiscal years | 0 |  | $ 0 |
Texas-New Mexico Power Company | Pension Plan | Minimum |  |  |  |
Components of Net Periodic Benefit Cost |  |  |  |
Assumptions used calculating net periodic benefit cost, discount rate |  |  | 4.10% |
Texas-New Mexico Power Company | Pension Plan | Maximum |  |  |  |
Components of Net Periodic Benefit Cost |  |  |  |
Assumptions used calculating net periodic benefit cost, discount rate |  |  | 4.90% |
Texas-New Mexico Power Company | OPEB Plan |  |  |  |
Components of Net Periodic Benefit Cost |  |  |  |
Service cost | 36,000 | 46,000 | $ 72,000 | 93,000
Interest cost | 139,000 | 169,000 | 278,000 | 339,000
Expected return on plan assets | (114,000) | (122,000) | (228,000) | (245,000)
Amortization of net (gain) loss | (20,000) | (10,000) | (40,000) | (20,000)
Amortization of prior service cost | 0 | 0 | 0 | 0
Net Periodic Benefit Cost | 41,000 | 83,000 | 82,000 | 167,000
Contributions by employer | 0 | 0 | 700,000 | 0
Total expected employer contributions for future fiscal years | 1,400,000 |  | 1,400,000 |
Total expected employer contributions for fiscal year | 0 |  | 0 |
Texas-New Mexico Power Company | Executive Retirement Program |  |  |  |
Components of Net Periodic Benefit Cost |  |  |  |
Service cost | 0 | 0 | 0 | 0
Interest cost | 8,000 | 10,000 | 17,000 | 20,000
Expected return on plan assets | 0 | 0 | 0 | 0
Amortization of net (gain) loss | 2,000 | 1,000 | 4,000 | 1,000
Amortization of prior service cost | 0 | 0 | 0 | 0
Net Periodic Benefit Cost | 10,000 | 11,000 | 21,000 | 21,000
Total expected employer contributions for future fiscal years | 400,000 |  | 400,000 |
Total expected employer contributions for fiscal year | 100,000 |  | 100,000 |
Texas-New Mexico Power Company | Executive Retirement Program | Maximum |  |  |  |
Components of Net Periodic Benefit Cost |  |  |  |
Contributions by employer | $ 100,000 | $ 100,000 | $ 100,000 | $ 100,000

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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(4) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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