Benefit Plans
|
9 Months Ended |
Sep. 30, 2015 |
|---|
| Benefit Plans |
BENEFIT PLANS
We sponsor a qualified pension plan and two unfunded nonqualified pension plans. Substantially all of our employees are covered by the qualified plan or both the qualified and a nonqualified pension plan. We sponsor OPEB plans to provide health and life insurance benefits for retired employees.
Components of Net Periodic Benefit Cost
The following tables provide the components of our net periodic benefit cost (credit) for the plans for the three and nine months ended September 30, 2015 and 2014: | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in millions) | Service Cost | $ | 23 |
| | $ | 18 |
| | $ | 3 |
| | $ | 4 |
| Interest Cost | 51 |
| | 55 |
| | 15 |
| | 16 |
| Expected Return on Plan Assets | (69 | ) | | (65 | ) | | (28 | ) | | (28 | ) | Amortization of Prior Service Cost (Credit) | 1 |
| | 1 |
| | (18 | ) | | (18 | ) | Amortization of Net Actuarial Loss | 27 |
| | 31 |
| | 5 |
| | 6 |
| Net Periodic Benefit Cost (Credit) | $ | 33 |
| | $ | 40 |
| | $ | (23 | ) | | $ | (20 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in millions) | Service Cost | $ | 70 |
| | $ | 54 |
| | $ | 9 |
| | $ | 11 |
| Interest Cost | 154 |
| | 166 |
| | 43 |
| | 50 |
| Expected Return on Plan Assets | (206 | ) | | (196 | ) | | (83 | ) | | (84 | ) | Amortization of Prior Service Cost (Credit) | 2 |
| | 2 |
| | (52 | ) | | (52 | ) | Amortization of Net Actuarial Loss | 80 |
| | 93 |
| | 14 |
| | 17 |
| Net Periodic Benefit Cost (Credit) | $ | 100 |
| | $ | 119 |
| | $ | (69 | ) | | $ | (58 | ) |
|
| Appalachian Power Co [Member] |
|
| Benefit Plans |
BENEFIT PLANS
The Registrant Subsidiaries participate in an AEP sponsored qualified pension plan and two unfunded nonqualified pension plans. Substantially all employees are covered by the qualified plan or both the qualified and a nonqualified pension plan. The Registrant Subsidiaries also participate in OPEB plans sponsored by AEP to provide health and life insurance benefits for retired employees.
Components of Net Periodic Benefit Cost
The following tables provide the components of net periodic benefit cost (credit) by Registrant Subsidiary for the plans for the three and nine months ended September 30, 2015 and 2014:
APCo | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 |
| 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 2,175 |
| | $ | 1,759 |
| | $ | 286 |
| | $ | 362 |
| Interest Cost | 6,679 |
| | 7,406 |
| | 2,584 |
| | 3,197 |
| Expected Return on Plan Assets | (8,745 | ) | | (8,482 | ) | | (4,529 | ) | | (4,634 | ) | Amortization of Prior Service Cost (Credit) | 45 |
| | 49 |
| | (2,513 | ) | | (2,512 | ) | Amortization of Net Actuarial Loss | 3,474 |
| | 4,149 |
| | 900 |
| | 1,145 |
| Net Periodic Benefit Cost (Credit) | $ | 3,628 |
| | $ | 4,881 |
| | $ | (3,272 | ) | | $ | (2,442 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 6,525 |
| | $ | 5,277 |
| | $ | 857 |
| | $ | 1,086 |
| Interest Cost | 20,037 |
| | 22,218 |
| | 7,753 |
| | 9,591 |
| Expected Return on Plan Assets | (26,236 | ) | | (25,445 | ) | | (13,587 | ) | | (13,900 | ) | Amortization of Prior Service Cost (Credit) | 135 |
| | 148 |
| | (7,538 | ) | | (7,537 | ) | Amortization of Net Actuarial Loss | 10,421 |
| | 12,445 |
| | 2,699 |
| | 3,436 |
| Net Periodic Benefit Cost (Credit) | $ | 10,882 |
| | $ | 14,643 |
| | $ | (9,816 | ) | | $ | (7,324 | ) |
I&M | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 3,217 |
| | $ | 2,517 |
| | $ | 406 |
| | $ | 486 |
| Interest Cost | 6,114 |
| | 6,573 |
| | 1,592 |
| | 1,909 |
| Expected Return on Plan Assets | (8,115 | ) | | (7,749 | ) | | (3,304 | ) | | (3,363 | ) | Amortization of Prior Service Cost (Credit) | 45 |
| | 49 |
| | (2,355 | ) | | (2,355 | ) | Amortization of Net Actuarial Loss | 3,145 |
| | 3,647 |
| | 506 |
| | 592 |
| Net Periodic Benefit Cost (Credit) | $ | 4,406 |
| | $ | 5,037 |
| | $ | (3,155 | ) | | $ | (2,731 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 9,651 |
| | $ | 7,551 |
| | $ | 1,219 |
| | $ | 1,460 |
| Interest Cost | 18,344 |
| | 19,720 |
| | 4,776 |
| | 5,728 |
| Expected Return on Plan Assets | (24,347 | ) | | (23,245 | ) | | (9,912 | ) | | (10,090 | ) | Amortization of Prior Service Cost (Credit) | 136 |
| | 146 |
| | (7,066 | ) | | (7,066 | ) | Amortization of Net Actuarial Loss | 9,434 |
| | 10,939 |
| | 1,519 |
| | 1,776 |
| Net Periodic Benefit Cost (Credit) | $ | 13,218 |
| | $ | 15,111 |
| | $ | (9,464 | ) | | $ | (8,192 | ) |
OPCo | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 1,671 |
| | $ | 1,285 |
| | $ | 216 |
| | $ | 256 |
| Interest Cost | 5,071 |
| | 5,527 |
| | 1,615 |
| | 1,900 |
| Expected Return on Plan Assets | (6,878 | ) | | (6,607 | ) | | (3,376 | ) | | (3,379 | ) | Amortization of Prior Service Cost (Credit) | 35 |
| | 40 |
| | (1,731 | ) | | (1,731 | ) | Amortization of Net Actuarial Loss | 2,644 |
| | 3,105 |
| | 517 |
| | 595 |
| Net Periodic Benefit Cost (Credit) | $ | 2,543 |
| | $ | 3,350 |
| | $ | (2,759 | ) | | $ | (2,359 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 5,015 |
| | $ | 3,855 |
| | $ | 647 |
| | $ | 769 |
| Interest Cost | 15,211 |
| | 16,579 |
| | 4,845 |
| | 5,701 |
| Expected Return on Plan Assets | (20,634 | ) | | (19,820 | ) | | (10,130 | ) | | (10,139 | ) | Amortization of Prior Service Cost (Credit) | 105 |
| | 118 |
| | (5,192 | ) | | (5,192 | ) | Amortization of Net Actuarial Loss | 7,932 |
| | 9,316 |
| | 1,552 |
| | 1,785 |
| Net Periodic Benefit Cost (Credit) | $ | 7,629 |
| | $ | 10,048 |
| | $ | (8,278 | ) | | $ | (7,076 | ) |
PSO | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 1,598 |
| | $ | 1,301 |
| | $ | 170 |
| | $ | 209 |
| Interest Cost | 2,731 |
| | 3,015 |
| | 759 |
| | 893 |
| Expected Return on Plan Assets | (3,786 | ) | | (3,651 | ) | | (1,578 | ) | | (1,575 | ) | Amortization of Prior Service Cost (Credit) | 63 |
| | 74 |
| | (1,072 | ) | | (1,072 | ) | Amortization of Net Actuarial Loss | 1,418 |
| | 1,689 |
| | 242 |
| | 278 |
| Net Periodic Benefit Cost (Credit) | $ | 2,024 |
| | $ | 2,428 |
| | $ | (1,479 | ) | | $ | (1,267 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 4,796 |
| | $ | 3,905 |
| | $ | 509 |
| | $ | 629 |
| Interest Cost | 8,194 |
| | 9,043 |
| | 2,277 |
| | 2,680 |
| Expected Return on Plan Assets | (11,358 | ) | | (10,953 | ) | | (4,732 | ) | | (4,725 | ) | Amortization of Prior Service Cost (Credit) | 189 |
| | 222 |
| | (3,217 | ) | | (3,217 | ) | Amortization of Net Actuarial Loss | 4,252 |
| | 5,065 |
| | 725 |
| | 832 |
| Net Periodic Benefit Cost (Credit) | $ | 6,073 |
| | $ | 7,282 |
| | $ | (4,438 | ) | | $ | (3,801 | ) |
SWEPCo | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 2,081 |
| | $ | 1,655 |
| | $ | 211 |
| | $ | 253 |
| Interest Cost | 2,932 |
| | 3,163 |
| | 837 |
| | 998 |
| Expected Return on Plan Assets | (4,008 | ) | | (3,857 | ) | | (1,735 | ) | | (1,754 | ) | Amortization of Prior Service Cost (Credit) | 78 |
| | 87 |
| | (1,289 | ) | | (1,289 | ) | Amortization of Net Actuarial Loss | 1,506 |
| | 1,762 |
| | 266 |
| | 309 |
| Net Periodic Benefit Cost (Credit) | $ | 2,589 |
| | $ | 2,810 |
| | $ | (1,710 | ) | | $ | (1,483 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 6,244 |
| | $ | 4,964 |
| | $ | 632 |
| | $ | 759 |
| Interest Cost | 8,796 |
| | 9,488 |
| | 2,512 |
| | 2,994 |
| Expected Return on Plan Assets | (12,024 | ) | | (11,571 | ) | | (5,206 | ) | | (5,262 | ) | Amortization of Prior Service Cost (Credit) | 232 |
| | 262 |
| | (3,867 | ) | | (3,867 | ) | Amortization of Net Actuarial Loss | 4,520 |
| | 5,285 |
| | 798 |
| | 926 |
| Net Periodic Benefit Cost (Credit) | $ | 7,768 |
| | $ | 8,428 |
| | $ | (5,131 | ) | | $ | (4,450 | ) |
|
| Indiana Michigan Power Co [Member] |
|
| Benefit Plans |
BENEFIT PLANS
The Registrant Subsidiaries participate in an AEP sponsored qualified pension plan and two unfunded nonqualified pension plans. Substantially all employees are covered by the qualified plan or both the qualified and a nonqualified pension plan. The Registrant Subsidiaries also participate in OPEB plans sponsored by AEP to provide health and life insurance benefits for retired employees.
Components of Net Periodic Benefit Cost
The following tables provide the components of net periodic benefit cost (credit) by Registrant Subsidiary for the plans for the three and nine months ended September 30, 2015 and 2014:
APCo | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 |
| 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 2,175 |
| | $ | 1,759 |
| | $ | 286 |
| | $ | 362 |
| Interest Cost | 6,679 |
| | 7,406 |
| | 2,584 |
| | 3,197 |
| Expected Return on Plan Assets | (8,745 | ) | | (8,482 | ) | | (4,529 | ) | | (4,634 | ) | Amortization of Prior Service Cost (Credit) | 45 |
| | 49 |
| | (2,513 | ) | | (2,512 | ) | Amortization of Net Actuarial Loss | 3,474 |
| | 4,149 |
| | 900 |
| | 1,145 |
| Net Periodic Benefit Cost (Credit) | $ | 3,628 |
| | $ | 4,881 |
| | $ | (3,272 | ) | | $ | (2,442 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 6,525 |
| | $ | 5,277 |
| | $ | 857 |
| | $ | 1,086 |
| Interest Cost | 20,037 |
| | 22,218 |
| | 7,753 |
| | 9,591 |
| Expected Return on Plan Assets | (26,236 | ) | | (25,445 | ) | | (13,587 | ) | | (13,900 | ) | Amortization of Prior Service Cost (Credit) | 135 |
| | 148 |
| | (7,538 | ) | | (7,537 | ) | Amortization of Net Actuarial Loss | 10,421 |
| | 12,445 |
| | 2,699 |
| | 3,436 |
| Net Periodic Benefit Cost (Credit) | $ | 10,882 |
| | $ | 14,643 |
| | $ | (9,816 | ) | | $ | (7,324 | ) |
I&M | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 3,217 |
| | $ | 2,517 |
| | $ | 406 |
| | $ | 486 |
| Interest Cost | 6,114 |
| | 6,573 |
| | 1,592 |
| | 1,909 |
| Expected Return on Plan Assets | (8,115 | ) | | (7,749 | ) | | (3,304 | ) | | (3,363 | ) | Amortization of Prior Service Cost (Credit) | 45 |
| | 49 |
| | (2,355 | ) | | (2,355 | ) | Amortization of Net Actuarial Loss | 3,145 |
| | 3,647 |
| | 506 |
| | 592 |
| Net Periodic Benefit Cost (Credit) | $ | 4,406 |
| | $ | 5,037 |
| | $ | (3,155 | ) | | $ | (2,731 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 9,651 |
| | $ | 7,551 |
| | $ | 1,219 |
| | $ | 1,460 |
| Interest Cost | 18,344 |
| | 19,720 |
| | 4,776 |
| | 5,728 |
| Expected Return on Plan Assets | (24,347 | ) | | (23,245 | ) | | (9,912 | ) | | (10,090 | ) | Amortization of Prior Service Cost (Credit) | 136 |
| | 146 |
| | (7,066 | ) | | (7,066 | ) | Amortization of Net Actuarial Loss | 9,434 |
| | 10,939 |
| | 1,519 |
| | 1,776 |
| Net Periodic Benefit Cost (Credit) | $ | 13,218 |
| | $ | 15,111 |
| | $ | (9,464 | ) | | $ | (8,192 | ) |
OPCo | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 1,671 |
| | $ | 1,285 |
| | $ | 216 |
| | $ | 256 |
| Interest Cost | 5,071 |
| | 5,527 |
| | 1,615 |
| | 1,900 |
| Expected Return on Plan Assets | (6,878 | ) | | (6,607 | ) | | (3,376 | ) | | (3,379 | ) | Amortization of Prior Service Cost (Credit) | 35 |
| | 40 |
| | (1,731 | ) | | (1,731 | ) | Amortization of Net Actuarial Loss | 2,644 |
| | 3,105 |
| | 517 |
| | 595 |
| Net Periodic Benefit Cost (Credit) | $ | 2,543 |
| | $ | 3,350 |
| | $ | (2,759 | ) | | $ | (2,359 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 5,015 |
| | $ | 3,855 |
| | $ | 647 |
| | $ | 769 |
| Interest Cost | 15,211 |
| | 16,579 |
| | 4,845 |
| | 5,701 |
| Expected Return on Plan Assets | (20,634 | ) | | (19,820 | ) | | (10,130 | ) | | (10,139 | ) | Amortization of Prior Service Cost (Credit) | 105 |
| | 118 |
| | (5,192 | ) | | (5,192 | ) | Amortization of Net Actuarial Loss | 7,932 |
| | 9,316 |
| | 1,552 |
| | 1,785 |
| Net Periodic Benefit Cost (Credit) | $ | 7,629 |
| | $ | 10,048 |
| | $ | (8,278 | ) | | $ | (7,076 | ) |
PSO | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 1,598 |
| | $ | 1,301 |
| | $ | 170 |
| | $ | 209 |
| Interest Cost | 2,731 |
| | 3,015 |
| | 759 |
| | 893 |
| Expected Return on Plan Assets | (3,786 | ) | | (3,651 | ) | | (1,578 | ) | | (1,575 | ) | Amortization of Prior Service Cost (Credit) | 63 |
| | 74 |
| | (1,072 | ) | | (1,072 | ) | Amortization of Net Actuarial Loss | 1,418 |
| | 1,689 |
| | 242 |
| | 278 |
| Net Periodic Benefit Cost (Credit) | $ | 2,024 |
| | $ | 2,428 |
| | $ | (1,479 | ) | | $ | (1,267 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 4,796 |
| | $ | 3,905 |
| | $ | 509 |
| | $ | 629 |
| Interest Cost | 8,194 |
| | 9,043 |
| | 2,277 |
| | 2,680 |
| Expected Return on Plan Assets | (11,358 | ) | | (10,953 | ) | | (4,732 | ) | | (4,725 | ) | Amortization of Prior Service Cost (Credit) | 189 |
| | 222 |
| | (3,217 | ) | | (3,217 | ) | Amortization of Net Actuarial Loss | 4,252 |
| | 5,065 |
| | 725 |
| | 832 |
| Net Periodic Benefit Cost (Credit) | $ | 6,073 |
| | $ | 7,282 |
| | $ | (4,438 | ) | | $ | (3,801 | ) |
SWEPCo | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 2,081 |
| | $ | 1,655 |
| | $ | 211 |
| | $ | 253 |
| Interest Cost | 2,932 |
| | 3,163 |
| | 837 |
| | 998 |
| Expected Return on Plan Assets | (4,008 | ) | | (3,857 | ) | | (1,735 | ) | | (1,754 | ) | Amortization of Prior Service Cost (Credit) | 78 |
| | 87 |
| | (1,289 | ) | | (1,289 | ) | Amortization of Net Actuarial Loss | 1,506 |
| | 1,762 |
| | 266 |
| | 309 |
| Net Periodic Benefit Cost (Credit) | $ | 2,589 |
| | $ | 2,810 |
| | $ | (1,710 | ) | | $ | (1,483 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 6,244 |
| | $ | 4,964 |
| | $ | 632 |
| | $ | 759 |
| Interest Cost | 8,796 |
| | 9,488 |
| | 2,512 |
| | 2,994 |
| Expected Return on Plan Assets | (12,024 | ) | | (11,571 | ) | | (5,206 | ) | | (5,262 | ) | Amortization of Prior Service Cost (Credit) | 232 |
| | 262 |
| | (3,867 | ) | | (3,867 | ) | Amortization of Net Actuarial Loss | 4,520 |
| | 5,285 |
| | 798 |
| | 926 |
| Net Periodic Benefit Cost (Credit) | $ | 7,768 |
| | $ | 8,428 |
| | $ | (5,131 | ) | | $ | (4,450 | ) |
|
| Ohio Power Co [Member] |
|
| Benefit Plans |
BENEFIT PLANS
The Registrant Subsidiaries participate in an AEP sponsored qualified pension plan and two unfunded nonqualified pension plans. Substantially all employees are covered by the qualified plan or both the qualified and a nonqualified pension plan. The Registrant Subsidiaries also participate in OPEB plans sponsored by AEP to provide health and life insurance benefits for retired employees.
Components of Net Periodic Benefit Cost
The following tables provide the components of net periodic benefit cost (credit) by Registrant Subsidiary for the plans for the three and nine months ended September 30, 2015 and 2014:
APCo | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 |
| 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 2,175 |
| | $ | 1,759 |
| | $ | 286 |
| | $ | 362 |
| Interest Cost | 6,679 |
| | 7,406 |
| | 2,584 |
| | 3,197 |
| Expected Return on Plan Assets | (8,745 | ) | | (8,482 | ) | | (4,529 | ) | | (4,634 | ) | Amortization of Prior Service Cost (Credit) | 45 |
| | 49 |
| | (2,513 | ) | | (2,512 | ) | Amortization of Net Actuarial Loss | 3,474 |
| | 4,149 |
| | 900 |
| | 1,145 |
| Net Periodic Benefit Cost (Credit) | $ | 3,628 |
| | $ | 4,881 |
| | $ | (3,272 | ) | | $ | (2,442 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 6,525 |
| | $ | 5,277 |
| | $ | 857 |
| | $ | 1,086 |
| Interest Cost | 20,037 |
| | 22,218 |
| | 7,753 |
| | 9,591 |
| Expected Return on Plan Assets | (26,236 | ) | | (25,445 | ) | | (13,587 | ) | | (13,900 | ) | Amortization of Prior Service Cost (Credit) | 135 |
| | 148 |
| | (7,538 | ) | | (7,537 | ) | Amortization of Net Actuarial Loss | 10,421 |
| | 12,445 |
| | 2,699 |
| | 3,436 |
| Net Periodic Benefit Cost (Credit) | $ | 10,882 |
| | $ | 14,643 |
| | $ | (9,816 | ) | | $ | (7,324 | ) |
I&M | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 3,217 |
| | $ | 2,517 |
| | $ | 406 |
| | $ | 486 |
| Interest Cost | 6,114 |
| | 6,573 |
| | 1,592 |
| | 1,909 |
| Expected Return on Plan Assets | (8,115 | ) | | (7,749 | ) | | (3,304 | ) | | (3,363 | ) | Amortization of Prior Service Cost (Credit) | 45 |
| | 49 |
| | (2,355 | ) | | (2,355 | ) | Amortization of Net Actuarial Loss | 3,145 |
| | 3,647 |
| | 506 |
| | 592 |
| Net Periodic Benefit Cost (Credit) | $ | 4,406 |
| | $ | 5,037 |
| | $ | (3,155 | ) | | $ | (2,731 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 9,651 |
| | $ | 7,551 |
| | $ | 1,219 |
| | $ | 1,460 |
| Interest Cost | 18,344 |
| | 19,720 |
| | 4,776 |
| | 5,728 |
| Expected Return on Plan Assets | (24,347 | ) | | (23,245 | ) | | (9,912 | ) | | (10,090 | ) | Amortization of Prior Service Cost (Credit) | 136 |
| | 146 |
| | (7,066 | ) | | (7,066 | ) | Amortization of Net Actuarial Loss | 9,434 |
| | 10,939 |
| | 1,519 |
| | 1,776 |
| Net Periodic Benefit Cost (Credit) | $ | 13,218 |
| | $ | 15,111 |
| | $ | (9,464 | ) | | $ | (8,192 | ) |
OPCo | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 1,671 |
| | $ | 1,285 |
| | $ | 216 |
| | $ | 256 |
| Interest Cost | 5,071 |
| | 5,527 |
| | 1,615 |
| | 1,900 |
| Expected Return on Plan Assets | (6,878 | ) | | (6,607 | ) | | (3,376 | ) | | (3,379 | ) | Amortization of Prior Service Cost (Credit) | 35 |
| | 40 |
| | (1,731 | ) | | (1,731 | ) | Amortization of Net Actuarial Loss | 2,644 |
| | 3,105 |
| | 517 |
| | 595 |
| Net Periodic Benefit Cost (Credit) | $ | 2,543 |
| | $ | 3,350 |
| | $ | (2,759 | ) | | $ | (2,359 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 5,015 |
| | $ | 3,855 |
| | $ | 647 |
| | $ | 769 |
| Interest Cost | 15,211 |
| | 16,579 |
| | 4,845 |
| | 5,701 |
| Expected Return on Plan Assets | (20,634 | ) | | (19,820 | ) | | (10,130 | ) | | (10,139 | ) | Amortization of Prior Service Cost (Credit) | 105 |
| | 118 |
| | (5,192 | ) | | (5,192 | ) | Amortization of Net Actuarial Loss | 7,932 |
| | 9,316 |
| | 1,552 |
| | 1,785 |
| Net Periodic Benefit Cost (Credit) | $ | 7,629 |
| | $ | 10,048 |
| | $ | (8,278 | ) | | $ | (7,076 | ) |
PSO | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 1,598 |
| | $ | 1,301 |
| | $ | 170 |
| | $ | 209 |
| Interest Cost | 2,731 |
| | 3,015 |
| | 759 |
| | 893 |
| Expected Return on Plan Assets | (3,786 | ) | | (3,651 | ) | | (1,578 | ) | | (1,575 | ) | Amortization of Prior Service Cost (Credit) | 63 |
| | 74 |
| | (1,072 | ) | | (1,072 | ) | Amortization of Net Actuarial Loss | 1,418 |
| | 1,689 |
| | 242 |
| | 278 |
| Net Periodic Benefit Cost (Credit) | $ | 2,024 |
| | $ | 2,428 |
| | $ | (1,479 | ) | | $ | (1,267 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 4,796 |
| | $ | 3,905 |
| | $ | 509 |
| | $ | 629 |
| Interest Cost | 8,194 |
| | 9,043 |
| | 2,277 |
| | 2,680 |
| Expected Return on Plan Assets | (11,358 | ) | | (10,953 | ) | | (4,732 | ) | | (4,725 | ) | Amortization of Prior Service Cost (Credit) | 189 |
| | 222 |
| | (3,217 | ) | | (3,217 | ) | Amortization of Net Actuarial Loss | 4,252 |
| | 5,065 |
| | 725 |
| | 832 |
| Net Periodic Benefit Cost (Credit) | $ | 6,073 |
| | $ | 7,282 |
| | $ | (4,438 | ) | | $ | (3,801 | ) |
SWEPCo | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 2,081 |
| | $ | 1,655 |
| | $ | 211 |
| | $ | 253 |
| Interest Cost | 2,932 |
| | 3,163 |
| | 837 |
| | 998 |
| Expected Return on Plan Assets | (4,008 | ) | | (3,857 | ) | | (1,735 | ) | | (1,754 | ) | Amortization of Prior Service Cost (Credit) | 78 |
| | 87 |
| | (1,289 | ) | | (1,289 | ) | Amortization of Net Actuarial Loss | 1,506 |
| | 1,762 |
| | 266 |
| | 309 |
| Net Periodic Benefit Cost (Credit) | $ | 2,589 |
| | $ | 2,810 |
| | $ | (1,710 | ) | | $ | (1,483 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 6,244 |
| | $ | 4,964 |
| | $ | 632 |
| | $ | 759 |
| Interest Cost | 8,796 |
| | 9,488 |
| | 2,512 |
| | 2,994 |
| Expected Return on Plan Assets | (12,024 | ) | | (11,571 | ) | | (5,206 | ) | | (5,262 | ) | Amortization of Prior Service Cost (Credit) | 232 |
| | 262 |
| | (3,867 | ) | | (3,867 | ) | Amortization of Net Actuarial Loss | 4,520 |
| | 5,285 |
| | 798 |
| | 926 |
| Net Periodic Benefit Cost (Credit) | $ | 7,768 |
| | $ | 8,428 |
| | $ | (5,131 | ) | | $ | (4,450 | ) |
|
| Public Service Co Of Oklahoma [Member] |
|
| Benefit Plans |
BENEFIT PLANS
The Registrant Subsidiaries participate in an AEP sponsored qualified pension plan and two unfunded nonqualified pension plans. Substantially all employees are covered by the qualified plan or both the qualified and a nonqualified pension plan. The Registrant Subsidiaries also participate in OPEB plans sponsored by AEP to provide health and life insurance benefits for retired employees.
Components of Net Periodic Benefit Cost
The following tables provide the components of net periodic benefit cost (credit) by Registrant Subsidiary for the plans for the three and nine months ended September 30, 2015 and 2014:
APCo | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 |
| 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 2,175 |
| | $ | 1,759 |
| | $ | 286 |
| | $ | 362 |
| Interest Cost | 6,679 |
| | 7,406 |
| | 2,584 |
| | 3,197 |
| Expected Return on Plan Assets | (8,745 | ) | | (8,482 | ) | | (4,529 | ) | | (4,634 | ) | Amortization of Prior Service Cost (Credit) | 45 |
| | 49 |
| | (2,513 | ) | | (2,512 | ) | Amortization of Net Actuarial Loss | 3,474 |
| | 4,149 |
| | 900 |
| | 1,145 |
| Net Periodic Benefit Cost (Credit) | $ | 3,628 |
| | $ | 4,881 |
| | $ | (3,272 | ) | | $ | (2,442 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 6,525 |
| | $ | 5,277 |
| | $ | 857 |
| | $ | 1,086 |
| Interest Cost | 20,037 |
| | 22,218 |
| | 7,753 |
| | 9,591 |
| Expected Return on Plan Assets | (26,236 | ) | | (25,445 | ) | | (13,587 | ) | | (13,900 | ) | Amortization of Prior Service Cost (Credit) | 135 |
| | 148 |
| | (7,538 | ) | | (7,537 | ) | Amortization of Net Actuarial Loss | 10,421 |
| | 12,445 |
| | 2,699 |
| | 3,436 |
| Net Periodic Benefit Cost (Credit) | $ | 10,882 |
| | $ | 14,643 |
| | $ | (9,816 | ) | | $ | (7,324 | ) |
I&M | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 3,217 |
| | $ | 2,517 |
| | $ | 406 |
| | $ | 486 |
| Interest Cost | 6,114 |
| | 6,573 |
| | 1,592 |
| | 1,909 |
| Expected Return on Plan Assets | (8,115 | ) | | (7,749 | ) | | (3,304 | ) | | (3,363 | ) | Amortization of Prior Service Cost (Credit) | 45 |
| | 49 |
| | (2,355 | ) | | (2,355 | ) | Amortization of Net Actuarial Loss | 3,145 |
| | 3,647 |
| | 506 |
| | 592 |
| Net Periodic Benefit Cost (Credit) | $ | 4,406 |
| | $ | 5,037 |
| | $ | (3,155 | ) | | $ | (2,731 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 9,651 |
| | $ | 7,551 |
| | $ | 1,219 |
| | $ | 1,460 |
| Interest Cost | 18,344 |
| | 19,720 |
| | 4,776 |
| | 5,728 |
| Expected Return on Plan Assets | (24,347 | ) | | (23,245 | ) | | (9,912 | ) | | (10,090 | ) | Amortization of Prior Service Cost (Credit) | 136 |
| | 146 |
| | (7,066 | ) | | (7,066 | ) | Amortization of Net Actuarial Loss | 9,434 |
| | 10,939 |
| | 1,519 |
| | 1,776 |
| Net Periodic Benefit Cost (Credit) | $ | 13,218 |
| | $ | 15,111 |
| | $ | (9,464 | ) | | $ | (8,192 | ) |
OPCo | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 1,671 |
| | $ | 1,285 |
| | $ | 216 |
| | $ | 256 |
| Interest Cost | 5,071 |
| | 5,527 |
| | 1,615 |
| | 1,900 |
| Expected Return on Plan Assets | (6,878 | ) | | (6,607 | ) | | (3,376 | ) | | (3,379 | ) | Amortization of Prior Service Cost (Credit) | 35 |
| | 40 |
| | (1,731 | ) | | (1,731 | ) | Amortization of Net Actuarial Loss | 2,644 |
| | 3,105 |
| | 517 |
| | 595 |
| Net Periodic Benefit Cost (Credit) | $ | 2,543 |
| | $ | 3,350 |
| | $ | (2,759 | ) | | $ | (2,359 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 5,015 |
| | $ | 3,855 |
| | $ | 647 |
| | $ | 769 |
| Interest Cost | 15,211 |
| | 16,579 |
| | 4,845 |
| | 5,701 |
| Expected Return on Plan Assets | (20,634 | ) | | (19,820 | ) | | (10,130 | ) | | (10,139 | ) | Amortization of Prior Service Cost (Credit) | 105 |
| | 118 |
| | (5,192 | ) | | (5,192 | ) | Amortization of Net Actuarial Loss | 7,932 |
| | 9,316 |
| | 1,552 |
| | 1,785 |
| Net Periodic Benefit Cost (Credit) | $ | 7,629 |
| | $ | 10,048 |
| | $ | (8,278 | ) | | $ | (7,076 | ) |
PSO | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 1,598 |
| | $ | 1,301 |
| | $ | 170 |
| | $ | 209 |
| Interest Cost | 2,731 |
| | 3,015 |
| | 759 |
| | 893 |
| Expected Return on Plan Assets | (3,786 | ) | | (3,651 | ) | | (1,578 | ) | | (1,575 | ) | Amortization of Prior Service Cost (Credit) | 63 |
| | 74 |
| | (1,072 | ) | | (1,072 | ) | Amortization of Net Actuarial Loss | 1,418 |
| | 1,689 |
| | 242 |
| | 278 |
| Net Periodic Benefit Cost (Credit) | $ | 2,024 |
| | $ | 2,428 |
| | $ | (1,479 | ) | | $ | (1,267 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 4,796 |
| | $ | 3,905 |
| | $ | 509 |
| | $ | 629 |
| Interest Cost | 8,194 |
| | 9,043 |
| | 2,277 |
| | 2,680 |
| Expected Return on Plan Assets | (11,358 | ) | | (10,953 | ) | | (4,732 | ) | | (4,725 | ) | Amortization of Prior Service Cost (Credit) | 189 |
| | 222 |
| | (3,217 | ) | | (3,217 | ) | Amortization of Net Actuarial Loss | 4,252 |
| | 5,065 |
| | 725 |
| | 832 |
| Net Periodic Benefit Cost (Credit) | $ | 6,073 |
| | $ | 7,282 |
| | $ | (4,438 | ) | | $ | (3,801 | ) |
SWEPCo | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 2,081 |
| | $ | 1,655 |
| | $ | 211 |
| | $ | 253 |
| Interest Cost | 2,932 |
| | 3,163 |
| | 837 |
| | 998 |
| Expected Return on Plan Assets | (4,008 | ) | | (3,857 | ) | | (1,735 | ) | | (1,754 | ) | Amortization of Prior Service Cost (Credit) | 78 |
| | 87 |
| | (1,289 | ) | | (1,289 | ) | Amortization of Net Actuarial Loss | 1,506 |
| | 1,762 |
| | 266 |
| | 309 |
| Net Periodic Benefit Cost (Credit) | $ | 2,589 |
| | $ | 2,810 |
| | $ | (1,710 | ) | | $ | (1,483 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 6,244 |
| | $ | 4,964 |
| | $ | 632 |
| | $ | 759 |
| Interest Cost | 8,796 |
| | 9,488 |
| | 2,512 |
| | 2,994 |
| Expected Return on Plan Assets | (12,024 | ) | | (11,571 | ) | | (5,206 | ) | | (5,262 | ) | Amortization of Prior Service Cost (Credit) | 232 |
| | 262 |
| | (3,867 | ) | | (3,867 | ) | Amortization of Net Actuarial Loss | 4,520 |
| | 5,285 |
| | 798 |
| | 926 |
| Net Periodic Benefit Cost (Credit) | $ | 7,768 |
| | $ | 8,428 |
| | $ | (5,131 | ) | | $ | (4,450 | ) |
|
| Southwestern Electric Power Co [Member] |
|
| Benefit Plans |
BENEFIT PLANS
The Registrant Subsidiaries participate in an AEP sponsored qualified pension plan and two unfunded nonqualified pension plans. Substantially all employees are covered by the qualified plan or both the qualified and a nonqualified pension plan. The Registrant Subsidiaries also participate in OPEB plans sponsored by AEP to provide health and life insurance benefits for retired employees.
Components of Net Periodic Benefit Cost
The following tables provide the components of net periodic benefit cost (credit) by Registrant Subsidiary for the plans for the three and nine months ended September 30, 2015 and 2014:
APCo | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 |
| 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 2,175 |
| | $ | 1,759 |
| | $ | 286 |
| | $ | 362 |
| Interest Cost | 6,679 |
| | 7,406 |
| | 2,584 |
| | 3,197 |
| Expected Return on Plan Assets | (8,745 | ) | | (8,482 | ) | | (4,529 | ) | | (4,634 | ) | Amortization of Prior Service Cost (Credit) | 45 |
| | 49 |
| | (2,513 | ) | | (2,512 | ) | Amortization of Net Actuarial Loss | 3,474 |
| | 4,149 |
| | 900 |
| | 1,145 |
| Net Periodic Benefit Cost (Credit) | $ | 3,628 |
| | $ | 4,881 |
| | $ | (3,272 | ) | | $ | (2,442 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 6,525 |
| | $ | 5,277 |
| | $ | 857 |
| | $ | 1,086 |
| Interest Cost | 20,037 |
| | 22,218 |
| | 7,753 |
| | 9,591 |
| Expected Return on Plan Assets | (26,236 | ) | | (25,445 | ) | | (13,587 | ) | | (13,900 | ) | Amortization of Prior Service Cost (Credit) | 135 |
| | 148 |
| | (7,538 | ) | | (7,537 | ) | Amortization of Net Actuarial Loss | 10,421 |
| | 12,445 |
| | 2,699 |
| | 3,436 |
| Net Periodic Benefit Cost (Credit) | $ | 10,882 |
| | $ | 14,643 |
| | $ | (9,816 | ) | | $ | (7,324 | ) |
I&M | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 3,217 |
| | $ | 2,517 |
| | $ | 406 |
| | $ | 486 |
| Interest Cost | 6,114 |
| | 6,573 |
| | 1,592 |
| | 1,909 |
| Expected Return on Plan Assets | (8,115 | ) | | (7,749 | ) | | (3,304 | ) | | (3,363 | ) | Amortization of Prior Service Cost (Credit) | 45 |
| | 49 |
| | (2,355 | ) | | (2,355 | ) | Amortization of Net Actuarial Loss | 3,145 |
| | 3,647 |
| | 506 |
| | 592 |
| Net Periodic Benefit Cost (Credit) | $ | 4,406 |
| | $ | 5,037 |
| | $ | (3,155 | ) | | $ | (2,731 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 9,651 |
| | $ | 7,551 |
| | $ | 1,219 |
| | $ | 1,460 |
| Interest Cost | 18,344 |
| | 19,720 |
| | 4,776 |
| | 5,728 |
| Expected Return on Plan Assets | (24,347 | ) | | (23,245 | ) | | (9,912 | ) | | (10,090 | ) | Amortization of Prior Service Cost (Credit) | 136 |
| | 146 |
| | (7,066 | ) | | (7,066 | ) | Amortization of Net Actuarial Loss | 9,434 |
| | 10,939 |
| | 1,519 |
| | 1,776 |
| Net Periodic Benefit Cost (Credit) | $ | 13,218 |
| | $ | 15,111 |
| | $ | (9,464 | ) | | $ | (8,192 | ) |
OPCo | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 1,671 |
| | $ | 1,285 |
| | $ | 216 |
| | $ | 256 |
| Interest Cost | 5,071 |
| | 5,527 |
| | 1,615 |
| | 1,900 |
| Expected Return on Plan Assets | (6,878 | ) | | (6,607 | ) | | (3,376 | ) | | (3,379 | ) | Amortization of Prior Service Cost (Credit) | 35 |
| | 40 |
| | (1,731 | ) | | (1,731 | ) | Amortization of Net Actuarial Loss | 2,644 |
| | 3,105 |
| | 517 |
| | 595 |
| Net Periodic Benefit Cost (Credit) | $ | 2,543 |
| | $ | 3,350 |
| | $ | (2,759 | ) | | $ | (2,359 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 5,015 |
| | $ | 3,855 |
| | $ | 647 |
| | $ | 769 |
| Interest Cost | 15,211 |
| | 16,579 |
| | 4,845 |
| | 5,701 |
| Expected Return on Plan Assets | (20,634 | ) | | (19,820 | ) | | (10,130 | ) | | (10,139 | ) | Amortization of Prior Service Cost (Credit) | 105 |
| | 118 |
| | (5,192 | ) | | (5,192 | ) | Amortization of Net Actuarial Loss | 7,932 |
| | 9,316 |
| | 1,552 |
| | 1,785 |
| Net Periodic Benefit Cost (Credit) | $ | 7,629 |
| | $ | 10,048 |
| | $ | (8,278 | ) | | $ | (7,076 | ) |
PSO | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 1,598 |
| | $ | 1,301 |
| | $ | 170 |
| | $ | 209 |
| Interest Cost | 2,731 |
| | 3,015 |
| | 759 |
| | 893 |
| Expected Return on Plan Assets | (3,786 | ) | | (3,651 | ) | | (1,578 | ) | | (1,575 | ) | Amortization of Prior Service Cost (Credit) | 63 |
| | 74 |
| | (1,072 | ) | | (1,072 | ) | Amortization of Net Actuarial Loss | 1,418 |
| | 1,689 |
| | 242 |
| | 278 |
| Net Periodic Benefit Cost (Credit) | $ | 2,024 |
| | $ | 2,428 |
| | $ | (1,479 | ) | | $ | (1,267 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 4,796 |
| | $ | 3,905 |
| | $ | 509 |
| | $ | 629 |
| Interest Cost | 8,194 |
| | 9,043 |
| | 2,277 |
| | 2,680 |
| Expected Return on Plan Assets | (11,358 | ) | | (10,953 | ) | | (4,732 | ) | | (4,725 | ) | Amortization of Prior Service Cost (Credit) | 189 |
| | 222 |
| | (3,217 | ) | | (3,217 | ) | Amortization of Net Actuarial Loss | 4,252 |
| | 5,065 |
| | 725 |
| | 832 |
| Net Periodic Benefit Cost (Credit) | $ | 6,073 |
| | $ | 7,282 |
| | $ | (4,438 | ) | | $ | (3,801 | ) |
SWEPCo | | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Three Months Ended September 30, | | Three Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 2,081 |
| | $ | 1,655 |
| | $ | 211 |
| | $ | 253 |
| Interest Cost | 2,932 |
| | 3,163 |
| | 837 |
| | 998 |
| Expected Return on Plan Assets | (4,008 | ) | | (3,857 | ) | | (1,735 | ) | | (1,754 | ) | Amortization of Prior Service Cost (Credit) | 78 |
| | 87 |
| | (1,289 | ) | | (1,289 | ) | Amortization of Net Actuarial Loss | 1,506 |
| | 1,762 |
| | 266 |
| | 309 |
| Net Periodic Benefit Cost (Credit) | $ | 2,589 |
| | $ | 2,810 |
| | $ | (1,710 | ) | | $ | (1,483 | ) |
| | | | | | | | | | | | | | | | | | Pension Plans | | Other Postretirement Benefit Plans | | Nine Months Ended September 30, | | Nine Months Ended September 30, | | 2015 | | 2014 | | 2015 | | 2014 | | (in thousands) | Service Cost | $ | 6,244 |
| | $ | 4,964 |
| | $ | 632 |
| | $ | 759 |
| Interest Cost | 8,796 |
| | 9,488 |
| | 2,512 |
| | 2,994 |
| Expected Return on Plan Assets | (12,024 | ) | | (11,571 | ) | | (5,206 | ) | | (5,262 | ) | Amortization of Prior Service Cost (Credit) | 232 |
| | 262 |
| | (3,867 | ) | | (3,867 | ) | Amortization of Net Actuarial Loss | 4,520 |
| | 5,285 |
| | 798 |
| | 926 |
| Net Periodic Benefit Cost (Credit) | $ | 7,768 |
| | $ | 8,428 |
| | $ | (5,131 | ) | | $ | (4,450 | ) |
|