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Employee Benefit Plans (Tables) | 12 Months Ended
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Dec. 31, 2014
Pension and Post-Retirement Medical Plans: |
Employee benefit plans |
Schedule of Pension Plan's funded status and amounts recognized in balance sheets and the components of net pension cost and accrued post-retirement liability | The following table sets forth the Pension Plan’s and post-retirement medical plan’s funded status and amounts recognized in Registrant’s balance sheets and the components of net pension cost and accrued liability at December 31, 2014 and 2013:
|  | Pension Benefits |  | Post-Retirement Medical Benefits
(dollars in thousands) |  | 2014 |  | 2013 |  | 2014 |  | 2013
Change in Projected Benefit Obligation: |  |  |  |  |  |  |  |  |  |  |  |
Projected benefit obligation at beginning of year |  | $ | 152,680 |  |  | $ | 163,230 |  |  | $ | 11,388 |  |  | $ | 12,296 |
Service cost |  | 5,643 |  |  | 6,967 |  |  | 348 |  |  | 407 |
Interest cost |  | 7,520 |  |  | 6,907 |  |  | 495 |  |  | 439 |
Actuarial loss (gain) |  | 24,339 |  |  | (19,918 | ) |  | 437 |  |  | (1,340 | )
Benefits/expenses paid |  | (4,998 | ) |  | (4,506 | ) |  | (342 | ) |  | (414 | )
Projected benefit obligation at end of year |  | $ | 185,184 |  |  | $ | 152,680 |  |  | $ | 12,326 |  |  | $ | 11,388 |
Changes in Plan Assets: |  |  |  |  |  |  |  |  |  |  |  |
Fair value of plan assets at beginning of year |  | $ | 127,534 |  |  | $ | 107,638 |  |  | $ | 9,873 |  |  | $ | 8,359 |
Actual return on plan assets |  | 9,816 |  |  | 17,846 |  |  | 951 |  |  | 1,320 |
Employer contributions |  | 8,209 |  |  | 6,556 |  |  | 241 |  |  | 608 |
Benefits/expenses paid |  | (4,998 | ) |  | (4,506 | ) |  | (342 | ) |  | (414 | )
Fair value of plan assets at end of year |  | $ | 140,561 |  |  | $ | 127,534 |  |  | $ | 10,723 |  |  | $ | 9,873 |
Funded Status: |  |  |  |  |  |  |  |  |  |  |  |
Net amount recognized as accrued pension cost |  | $ | (44,623 | ) |  | $ | (25,146 | ) |  | $ | (1,603 | ) |  | $ | (1,515 | )
|  | Pension Benefits |  | Post-Retirement Medical Benefits
(in thousands) |  | 2014 |  | 2013 |  | 2014 |  | 2013
Amounts recognized on the balance sheets: |  |  |  |  |  |  |  |  |  |  |  |
Current liabilities |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Non-current liabilities |  | (44,623 | ) |  | (25,146 | ) |  | (1,603 | ) |  | (1,515 | )
Net amount recognized |  | $ | (44,623 | ) |  | $ | (25,146 | ) |  | $ | (1,603 | ) |  | $ | (1,515 | )
Amounts recognized in regulatory assets consist of: |  |  |  |  |  |  |  |  |  |  |  |
Initial net obligation |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 417 |
Prior service cost (credit) |  | 167 |  |  | 285 |  |  | (234 | ) |  | (433 | )
Net (gain) loss |  | 39,003 |  |  | 15,581 |  |  | (2,891 | ) |  | (3,159 | )
Regulatory assets (liabilities) |  | 39,170 |  |  | 15,866 |  |  | (3,125 | ) |  | (3,175 | )
Unfunded accrued pension cost |  | 5,453 |  |  | 9,280 |  |  | 4,728 |  |  | 4,690 |
Net liability recognized |  | $ | 44,623 |  |  | $ | 25,146 |  |  | $ | 1,603 |  |  | $ | 1,515 |
Changes in plan assets and benefit obligations recognized in regulatory assets: |  |  |  |  |  |  |  |  |  |  |  |
Regulatory asset at beginning of year |  | $ | 15,866 |  |  | $ | 49,052 |  |  | $ | (3,175 | ) |  | $ | (685 | )
Net loss (gain) |  | 23,422 |  |  | (30,190 | ) |  | (61 | ) |  | (2,278 | )
Amortization of initial net obligation |  | — |  |  | — |  |  | (419 | ) |  | (419 | )
Amortization of prior service (cost) credit |  | (118 | ) |  | (118 | ) |  | 200 |  |  | 200 |
Amortization of net gain (loss) |  | — |  |  | (2,878 | ) |  | 330 |  |  | 7 |
Total change in regulatory asset |  | 23,304 |  |  | (33,186 | ) |  | 50 |  |  | (2,490 | )
Regulatory asset (liability) at end of year |  | $ | 39,170 |  |  | $ | 15,866 |  |  | $ | (3,125 | ) |  | $ | (3,175 | )
Net periodic pension costs |  | $ | 4,383 |  |  | $ | 9,296 |  |  | $ | 278 |  |  | $ | 676 |
Change in regulatory asset |  | 23,304 |  |  | (33,186 | ) |  | 50 |  |  | (2,490 | )
Total recognized in net periodic pension cost and regulatory asset (liability) |  | $ | 27,687 |  |  | $ | (23,890 | ) |  | $ | 328 |  |  | $ | (1,814 | )
Estimated amounts that will be amortized from regulatory asset over the next fiscal year: |  |  |  |  |  |  |  |  |  |  |  |
Initial net obligation |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | (418 | )
Prior service (cost) credit |  | $ | (118 | ) |  | $ | (118 | ) |  | $ | 200 |  |  | $ | 200 |
Net gain (loss) |  | $ | (1,878 | ) |  | $ | (29 | ) |  | $ | 213 |  |  | $ | 262 |
Additional year-end information for plans with an accumulated benefit obligation in excess of plan assets: |  |  |  |  |  |  |  |  |  |  |  |
Projected benefit obligation |  | $ | 185,184 |  |  | $ | 152,680 |  |  | $ | 12,326 |  |  | $ | 11,388 |
Accumulated benefit obligation |  | $ | 160,510 |  |  | $ | 131,580 |  |  | N/A |  | N/A
Fair value of plan assets |  | $ | 140,561 |  |  | $ | 127,534 |  |  | $ | 10,723 |  |  | $ | 9,873 |
Weighted-average assumptions used to determine benefit obligations at December 31: |  |  |  |  |  |  |  |  |  |  |  |
Discount rate |  | 4.25 | % |  | 5.10 | % |  | 3.80 | % |  | 4.65 | %
Rate of compensation increase |  | 4.00 | % |  | 4.00 | % |  | N/A |  |  | N/A |
Schedule of components of net periodic pension and post-retirement benefits cost, before allocation to the overhead pool | The components of net periodic pension and post-retirement benefits cost, before allocation to the overhead pool, for 2014, 2013 and 2012 are as follows:
|  | Pension Benefits |  | Post-Retirement Medical Benefits
(dollars in thousands, except percent) |  | 2014 |  | 2013 |  | 2012 |  | 2014 |  | 2013 |  | 2012
Components of Net Periodic Benefits Cost: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Service cost |  | $ | 5,643 |  |  | $ | 6,967 |  |  | $ | 6,675 |  |  | $ | 348 |  |  | $ | 407 |  |  | $ | 419 |
Interest cost |  | 7,520 |  |  | 6,907 |  |  | 6,657 |  |  | 495 |  |  | 439 |  |  | 534 |
Expected return on plan assets |  | (8,898 | ) |  | (7,574 | ) |  | (6,540 | ) |  | (453 | ) |  | (382 | ) |  | (357 | )
Amortization of transition |  | — |  |  | — |  |  | — |  |  | 418 |  |  | 419 |  |  | 419 |
Amortization of prior service cost (credit) |  | 118 |  |  | 118 |  |  | 118 |  |  | (200 | ) |  | (200 | ) |  | (200 | )
Amortization of actuarial (gain) loss |  | — |  |  | 2,878 |  |  | 3,035 |  |  | (330 | ) |  | (7 | ) |  | — |
Net periodic pension cost under accounting standards |  | $ | 4,383 |  |  | $ | 9,296 |  |  | $ | 9,945 |  |  | $ | 278 |  |  | $ | 676 |  |  | $ | 815 |
Regulatory adjustment - over/(under) collection |  | 1,622 |  |  | (1,920 | ) |  | (2,305 | ) |  | — |  |  | — |  |  | — |
Total expense recognized, before allocation to overhead pool |  | $ | 6,005 |  |  | $ | 7,376 |  |  | $ | 7,640 |  |  | $ | 278 |  |  | $ | 676 |  |  | $ | 815 |
Weighted-average assumptions used to determine net periodic cost: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Discount rate |  | 5.10 | % |  | 4.30 | % |  | 4.65 | % |  | 4.65 | % |  | 3.75 | % |  | 4.45 | %
Expected long-term return on plan assets |  | 7.00 | % |  | 7.00 | % |  | 7.00 | % |  | * |  |  | * |  |  | * |
Rate of compensation increase |  | 4.00 | % |  | 4.00 | % |  | 4.00 | % |  | N/A |  |  | N/A |  |  | N/A |
*7.0% for union plan, 4.2% for non-union, net of income taxes in 2014, 2013 and 2012.
Schedule of pension and post-retirement plan weighted-average asset allocations, by asset category | The Committee approves the target asset allocations. Registrant’s pension and post-retirement plan weighted-average asset allocations at December 31, 2014 and 2013, by asset category are as follows:
|  | Pension Benefits |  | Post-Retirement Medical Benefits
Asset Category |  | 2014 |  | 2013 |  | 2014 |  | 2013
Actual Asset Allocations: |  |  |  |  |  |  |  |  |  |  |  |
Equity securities |  | 61 | % |  | 61 | % |  | 60 | % |  | 61 | %
Debt securities |  | 39 | % |  | 37 | % |  | 38 | % |  | 38 | %
Cash equivalents |  | — | % |  | 2 | % |  | 2 | % |  | 1 | %
Total |  | 100 | % |  | 100 | % |  | 100 | % |  | 100 | %
Schedule of pension and post-retirement plan target asset allocations | Equity securities did not include AWR’s stock as of December 31, 2014 and 2013.
Target Asset Allocations for 2015: |  | Pension Benefits |  | Post-retirement Medical Benefits
Equity securities |  | 60 | % |  | 60 | %
Debt securities |  | 40 | % |  | 40 | %
Total |  | 100 | % |  | 100 | %
Schedule of pension and post-retirement plans' investment assets measured at fair value | The following tables set forth by level, within the fair value hierarchy, the pension and post-retirement plans’ investment assets measured at fair value as of December 31, 2014 and 2013:
|  | Fair Value as of December 31, 2014
(dollars in thousands) |  | Level 1 |  | Level 2 |  | Level 3 |  | Total
Fair Value of Pension Plan Assets: |  |  |  |  |  |  |  |  |  |  |  |
Cash equivalents |  | $ | 497 |  |  | — |  |  | — |  |  | $ | 497 |
Fixed income securities |  | 54,865 |  |  | — |  |  | — |  |  | 54,865 |
Equity securities: |  |  |  |  |  |  |  |  |  |  |  |
U.S. small cap stocks |  | 7,546 |  |  | — |  |  | — |  |  | 7,546 |
U.S. mid cap stocks |  | 14,779 |  |  | — |  |  | — |  |  | 14,779 |
U.S. large cap stocks |  | 42,886 |  |  | — |  |  | — |  |  | 42,886 |
International funds |  | 11,318 |  |  | — |  |  | — |  |  | 11,318 |
Real estate funds |  | 8,670 |  |  | — |  |  | — |  |  | 8,670 |
Total equity securities |  | 85,199 |  |  | — |  |  | — |  |  | 85,199 |
Total investments measured at fair value |  | $ | 140,561 |  |  | — |  |  | — |  |  | $ | 140,561 |
Fair Value of Post-Retirement Plan Assets: |  |  |  |  |  |  |  |  |  |  |  |
Cash equivalents |  | $ | 185 |  |  | — |  |  | — |  |  | $ | 185 |
Fixed income |  | 4,105 |  |  | — |  |  | — |  |  | 4,105 |
U.S. equity securities (large cap stocks) |  | 6,433 |  |  | — |  |  | — |  |  | 6,433 |
Total investments measured at fair value |  | $ | 10,723 |  |  | — |  |  | — |  |  | $ | 10,723 |
|  | Fair Value as of December 31, 2013
(dollars in thousands) |  | Level 1 |  | Level 2 |  | Level 3 |  | Total
Fair Value of Pension Plan Assets: |  |  |  |  |  |  |  |  |  |  |  |
Cash equivalents |  | $ | 2,096 |  |  | — |  |  | — |  |  | $ | 2,096 |
Fixed income securities |  | 47,627 |  |  | — |  |  | — |  |  | 47,627 |
Equity securities: |  |  |  |  |  |  |  |  |  |  |  |
U.S. small cap stocks |  | 6,576 |  |  | — |  |  | — |  |  | 6,576 |
U.S. mid cap stocks |  | 13,119 |  |  | — |  |  | — |  |  | 13,119 |
U.S. large cap stocks |  | 39,280 |  |  | — |  |  | — |  |  | 39,280 |
International funds |  | 12,501 |  |  | — |  |  | — |  |  | 12,501 |
Real estate funds |  | 6,335 |  |  | — |  |  | — |  |  | 6,335 |
Total equity securities |  | 77,811 |  |  | — |  |  | — |  |  | 77,811 |
Total investments measured at fair value |  | $ | 127,534 |  |  | — |  |  | — |  |  | $ | 127,534 |
Fair Value of Post-Retirement Plan Assets: |  |  |  |  |  |  |  |  |  |  |  |
Cash equivalents |  | $ | 142 |  |  | — |  |  | — |  |  | $ | 142 |
Fixed income |  | 3,731 |  |  | — |  |  | — |  |  | 3,731 |
U.S. equity securities (large cap stocks) |  | 6,000 |  |  | — |  |  | — |  |  | 6,000 |
Total investments measured at fair value |  | $ | 9,873 |  |  | — |  |  | — |  |  | $ | 9,873 |
Schedule of estimated future benefit payments | Registrant’s estimated future benefit payments at December 31, 2014 for the next five years and thereafter are as follows (in thousands):
| Pension Benefits |  | Post-Retirement Medical Benefits
2015 | $ | 5,468 |  |  | $ | 566 |
2016 | 5,938 |  |  | 601 |
2017 | 6,489 |  |  | 680 |
2018 | 7,030 |  |  | 774 |
2019 | 7,569 |  |  | 866 |
Thereafter | 48,446 |  |  | 5,247 |
Total | $ | 80,940 |  |  | $ | 8,734 |
Schedule of effects of one-percentage-point change in assumed health care cost trend rates | A one-percentage-point change in assumed health care cost trend rates would have the following effects on the post-retirement medical plan:
(dollars in thousands) |  | 1-Percentage-Point Increase |  | 1-Percentage-Point Decrease
Effect on total of service and interest cost components |  | $ | 80 |  |  | $ | (70 | )
Effect on post-retirement benefit obligation |  | $ | 1,438 |  |  | $ | (1,232 | )
SERP |
Employee benefit plans |
Schedule of Pension Plan's funded status and amounts recognized in balance sheets and the components of net pension cost and accrued post-retirement liability | The following provides a reconciliation of benefit obligations, funded status of the SERP, as well as a summary of significant estimates at December 31, 2014 and 2013:
(dollars in thousands) |  | 2014 |  | 2013
Change in Benefit Obligation: |  |  |  |  |  |
Benefit obligation at beginning of year |  | $ | 12,296 |  |  | $ | 12,406 |
Service cost |  | 768 |  |  | 803 |
Interest cost |  | 615 |  |  | 514 |
Actuarial (gain) loss |  | 2,497 |  |  | (1,198 | )
Benefits paid |  | (250 | ) |  | (229 | )
Benefit obligation at end of year |  | $ | 15,926 |  |  | $ | 12,296 |
Changes in Plan Assets: |  |  |  |  |  |
Fair value of plan assets at beginning of year |  | — |  |  | — |
Fair value of plan assets at end of year |  | — |  |  | — |
Funded Status: |  |  |  |  |  |
Net amount recognized as accrued cost |  | $ | (15,926 | ) |  | $ | (12,296 | )
(in thousands) |  | 2014 |  | 2013
Amounts recognized on the balance sheets: |  |  |  |  |  |
Current liabilities |  | $ | (379 | ) |  | $ | (230 | )
Non-current liabilities |  | (15,547 | ) |  | (12,066 | )
Net amount recognized |  | $ | (15,926 | ) |  | $ | (12,296 | )
Amounts recognized in regulatory assets consist of: |  |  |  |  |  |
Prior service cost |  | $ | 153 |  |  | $ | 314 |
Net loss |  | 4,530 |  |  | 2,172 |
Regulatory assets |  | 4,683 |  |  | 2,486 |
Unfunded accrued cost |  | 11,243 |  |  | 9,810 |
Net liability recognized |  | $ | 15,926 |  |  | $ | 12,296 |
Changes in plan assets and benefit obligations recognized in regulatory assets consist of: |  |  |  |  |  |
Regulatory asset at beginning of year |  | $ | 2,486 |  |  | $ | 4,184 |
Net (gain) loss |  | 2,497 |  |  | (1,199 | )
Amortization of prior service credit |  | (161 | ) |  | (161 | )
Amortization of net loss |  | (139 | ) |  | (338 | )
Total change in regulatory asset |  | 2,197 |  |  | (1,698 | )
Regulatory asset at end of year |  | $ | 4,683 |  |  | $ | 2,486 |
Net periodic pension cost |  | $ | 1,683 |  |  | $ | 1,817 |
Change in regulatory asset |  | 2,197 |  |  | (1,698 | )
Total recognized in net periodic pension and net income |  | $ | 3,880 |  |  | $ | 119 |
Estimated amounts that will be amortized from regulatory asset over the next fiscal year: |  |  |  |  |  |
Initial net asset (obligation) |  | — |  |  | — |
Prior service cost |  | $ | (117 | ) |  | $ | (161 | )
Net loss |  | (431 | ) |  | (139 | )
Additional year-end information for plans with an accumulated benefit obligation in excess of plan assets: |  |  |  |  |  |
Projected benefit obligation |  | $ | 15,926 |  |  | $ | 12,296 |
Accumulated benefit obligation |  | 13,992 |  |  | 10,116 |
Fair value of plan assets |  | — |  |  | — |
Weighted-average assumptions used to determine benefit obligations: |  |  |  |  |  |
Discount rate |  | 4.15 | % |  | 5.05 | %
Rate of compensation increase |  | 4.00 | % |  | 4.00 | %
Schedule of components of net periodic pension and post-retirement benefits cost, before allocation to the overhead pool | The components of SERP expense, before allocation to the overhead pool, for 2014, 2013 and 2012 are as follows:
(dollars in thousands, except percent) |  | 2014 |  | 2013 |  | 2012
Components of Net Periodic Benefits Cost: |  |  |  |  |  |  |  |  |
Service cost |  | $ | 768 |  |  | $ | 803 |  |  | $ | 731 |
Interest cost |  | 615 |  |  | 514 |  |  | 488 |
Amortization of prior service cost |  | 161 |  |  | 161 |  |  | 161 |
Amortization of net loss |  | 139 |  |  | 339 |  |  | 307 |
Net periodic pension cost |  | $ | 1,683 |  |  | $ | 1,817 |  |  | $ | 1,687 |
Weighted-average assumptions used to determine net periodic cost: |  |  |  |  |  |  |  |  |
Discount rate |  | 5.05 | % |  | 4.20 | % |  | 4.65 | %
Rate of compensation increase |  | 4.00 | % |  | 4.00 | % |  | 4.00 | %
Schedule of pension and post-retirement plans' investment assets measured at fair value | The following tables set forth by level, within the fair value hierarchy, the Rabbi Trust investment assets measured at fair value as of December 31, 2014 and 2013.
|  | Fair Value as of December 31, 2014
(dollars in thousands) |  | Level 1 |  | Level 2 |  | Level 3 |  | Total
Fair Value of Assets held in Rabbi Trust: |  |  |  |  |  |  |  |  |  |  |  |
Cash equivalents |  | $ | 29 |  |  | — |  |  | — |  |  | $ | 29 |
Fixed income securities |  | 3,454 |  |  | — |  |  | — |  |  | 3,454 |
Equity securities |  | 5,282 |  |  | — |  |  | — |  |  | 5,282 |
Total investments measured at fair value |  | $ | 8,765 |  |  | — |  |  | — |  |  | $ | 8,765 |
|  | Fair Value as of December 31, 2013
(dollars in thousands) |  | Level 1 |  | Level 2 |  | Level 3 |  | Total
Fair Value of Assets held in Rabbi Trust: |  |  |  |  |  |  |  |  |  |  |  |
Cash equivalents |  | $ | 27 |  |  | — |  |  | — |  |  | $ | 27 |
Fixed income securities |  | 2,587 |  |  | — |  |  | — |  |  | 2,587 |
Equity securities |  | 4,202 |  |  | — |  |  | — |  |  | 4,202 |
Total investments measured at fair value |  | $ | 6,816 |  |  | — |  |  | — |  |  | $ | 6,816 |
Schedule of estimated future benefit payments | Registrant’s estimated future benefit payments for the SERP at December 31, 2014 for the next ten years are as follows (in thousands):
2015 | $ | 379 |
2016 | 391 |
2017 | 472 |
2018 | 614 |
2019 | 712 |
Thereafter | 5,402 |
Total | $ | 7,970 |

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