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v3.23.1

Benefit Plans (Tables) | 12 Months Ended
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Dec. 31, 2022
Health Care Trend Rates |
|  | December 31,
Health Care Trend Rates |  | 2022 |  | 2021
Initial |  | 7.50 | % |  | 6.25 | %
Ultimate |  | 4.50 | % |  | 4.50 | %
Year Ultimate Reached |  | 2029 |  | 2029
Reconciliation of Changes in Benefit Obligations and Fair Value of Assets |
AEP |  | Pension Plans |  | OPEB
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Change in Benefit Obligation |  | (in millions)
Benefit Obligation as of January 1, |  | $ | 5,187.0 |  |  | $ | 5,544.5 |  |  | $ | 1,041.3 |  |  | $ | 1,210.9 |
Service Cost |  | 123.1 |  |  | 129.2 |  |  | 7.4 |  |  | 9.5 |
Interest Cost |  | 148.2 |  |  | 137.2 |  |  | 29.2 |  |  | 30.5 |
Actuarial Gain |  | (983.4) |  |  | (173.9) |  |  | (109.8) |  |  | (120.1) |
Plan Amendments |  | — |  |  | — |  |  | — |  |  | (5.4) |
Benefit Payments |  | (402.2) |  |  | (450.0) |  |  | (140.1) |  |  | (126.0) |
Participant Contributions |  | — |  |  | — |  |  | 44.1 |  |  | 41.3 |
Medicare Subsidy |  | — |  |  | — |  |  | 0.5 |  |  | 0.6 |
Benefit Obligation as of December 31, |  | $ | 4,072.7 |  |  | $ | 5,187.0 |  |  | $ | 872.6 |  |  | $ | 1,041.3 |
Change in Fair Value of Plan Assets |  |  |  |  |  |  |  |
Fair Value of Plan Assets as of January 1, |  | $ | 5,352.9 |  |  | $ | 5,556.6 |  |  | $ | 2,044.3 |  |  | $ | 1,946.7 |
Actual Gain (Loss) on Plan Assets |  | (833.7) |  |  | 239.2 |  |  | (403.6) |  |  | 176.5 |
Company Contributions (a) |  | 7.7 |  |  | 7.1 |  |  | 4.6 |  |  | 5.8 |
Participant Contributions |  | — |  |  | — |  |  | 44.1 |  |  | 41.3 |
Benefit Payments |  | (402.2) |  |  | (450.0) |  |  | (140.1) |  |  | (126.0) |
Fair Value of Plan Assets as of December 31, |  | $ | 4,124.7 |  |  | $ | 5,352.9 |  |  | $ | 1,549.3 |  |  | $ | 2,044.3 |
Funded Status as of December 31, |  | $ | 52.0 |  |  | $ | 165.9 |  |  | $ | 676.7 |  |  | $ | 1,003.0 |
(a)No contributions were made to the qualified pension plan for the years ended December 31, 2022 and 2021, respectively. Contributions to the non-qualified pension plans were $8 million and $7 million for the years ended December 31, 2022 and 2021, respectively.
AEP Texas |  | Pension Plans |  | OPEB
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Change in Benefit Obligation |  | (in millions)
Benefit Obligation as of January 1, |  | $ | 419.8 |  |  | $ | 453.2 |  |  | $ | 80.5 |  |  | $ | 96.3 |
Service Cost |  | 11.1 |  |  | 11.8 |  |  | 0.5 |  |  | 0.7 |
Interest Cost |  | 12.1 |  |  | 11.2 |  |  | 2.2 |  |  | 2.4 |
Actuarial Gain |  | (67.8) |  |  | (10.9) |  |  | (7.1) |  |  | (12.3) |
Plan Amendments |  | — |  |  | — |  |  | — |  |  | (0.5) |
Benefit Payments |  | (41.1) |  |  | (45.5) |  |  | (10.9) |  |  | (9.3) |
Participant Contributions |  | — |  |  | — |  |  | 3.4 |  |  | 3.2 |
Benefit Obligation as of December 31, |  | $ | 334.1 |  |  | $ | 419.8 |  |  | $ | 68.6 |  |  | $ | 80.5 |
Change in Fair Value of Plan Assets |  |  |  |  |  |  |  |
Fair Value of Plan Assets as of January 1, |  | $ | 444.9 |  |  | $ | 474.0 |  |  | $ | 168.8 |  |  | $ | 162.3 |
Actual Gain (Loss) on Plan Assets |  | (69.2) |  |  | 16.0 |  |  | (33.0) |  |  | 12.5 |
Company Contributions |  | 0.5 |  |  | 0.4 |  |  | — |  |  | 0.1 |
Participant Contributions |  | — |  |  | — |  |  | 3.4 |  |  | 3.2 |
Benefit Payments |  | (41.1) |  |  | (45.5) |  |  | (10.9) |  |  | (9.3) |
Fair Value of Plan Assets as of December 31, |  | $ | 335.1 |  |  | $ | 444.9 |  |  | $ | 128.3 |  |  | $ | 168.8 |
Funded Status as of December 31, |  | $ | 1.0 |  |  | $ | 25.1 |  |  | $ | 59.7 |  |  | $ | 88.3 |
APCo |  | Pension Plans |  | OPEB
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Change in Benefit Obligation |  | (in millions)
Benefit Obligation as of January 1, |  | $ | 621.7 |  |  | $ | 670.8 |  |  | $ | 167.3 |  |  | $ | 198.2 |
Service Cost |  | 11.4 |  |  | 11.9 |  |  | 0.8 |  |  | 1.0 |
Interest Cost |  | 17.5 |  |  | 16.4 |  |  | 4.7 |  |  | 4.9 |
Actuarial Gain |  | (123.1) |  |  | (28.5) |  |  | (16.2) |  |  | (21.4) |
Plan Amendments |  | — |  |  | — |  |  | — |  |  | (0.9) |
Benefit Payments |  | (41.8) |  |  | (48.9) |  |  | (23.0) |  |  | (21.3) |
Participant Contributions |  | — |  |  | — |  |  | 7.0 |  |  | 6.6 |
Medicare Subsidy |  | — |  |  | — |  |  | 0.1 |  |  | 0.2 |
Benefit Obligation as of December 31, |  | $ | 485.7 |  |  | $ | 621.7 |  |  | $ | 140.7 |  |  | $ | 167.3 |
Change in Fair Value of Plan Assets |  |  |  |  |  |  |  |
Fair Value of Plan Assets as of January 1, |  | $ | 683.3 |  |  | $ | 701.3 |  |  | $ | 302.3 |  |  | $ | 293.0 |
Actual Gain (Loss) on Plan Assets |  | (109.8) |  |  | 30.9 |  |  | (59.3) |  |  | 21.9 |
Company Contributions |  | — |  |  | — |  |  | 1.6 |  |  | 2.1 |
Participant Contributions |  | — |  |  | — |  |  | 7.0 |  |  | 6.6 |
Benefit Payments |  | (41.8) |  |  | (48.9) |  |  | (23.0) |  |  | (21.3) |
Fair Value of Plan Assets as of December 31, |  | $ | 531.7 |  |  | $ | 683.3 |  |  | $ | 228.6 |  |  | $ | 302.3 |
Funded Status as of December 31, |  | $ | 46.0 |  |  | $ | 61.6 |  |  | $ | 87.9 |  |  | $ | 135.0 |
I&M |  | Pension Plans |  | OPEB
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Change in Benefit Obligation |  | (in millions)
Benefit Obligation as of January 1, |  | $ | 612.1 |  |  | $ | 653.3 |  |  | $ | 118.6 |  |  | $ | 141.4 |
Service Cost |  | 16.2 |  |  | 17.5 |  |  | 0.9 |  |  | 1.3 |
Interest Cost |  | 17.0 |  |  | 16.2 |  |  | 3.4 |  |  | 3.5 |
Actuarial Gain |  | (138.0) |  |  | (29.5) |  |  | (8.7) |  |  | (16.8) |
Plan Amendments |  | — |  |  | — |  |  | — |  |  | (0.7) |
Benefit Payments |  | (40.5) |  |  | (45.4) |  |  | (18.3) |  |  | (15.3) |
Participant Contributions |  | — |  |  | — |  |  | 6.0 |  |  | 5.2 |
Benefit Obligation as of December 31, |  | $ | 466.8 |  |  | $ | 612.1 |  |  | $ | 101.9 |  |  | $ | 118.6 |
Change in Fair Value of Plan Assets |  |  |  |  |  |  |  |
Fair Value of Plan Assets as of January 1, |  | $ | 681.5 |  |  | $ | 698.1 |  |  | $ | 248.7 |  |  | $ | 238.2 |
Actual Gain (Loss) on Plan Assets |  | (107.4) |  |  | 28.8 |  |  | (45.9) |  |  | 20.6 |
Company Contributions |  | 0.1 |  |  | — |  |  | — |  |  | — |
Participant Contributions |  | — |  |  | — |  |  | 6.0 |  |  | 5.2 |
Benefit Payments |  | (40.5) |  |  | (45.4) |  |  | (18.3) |  |  | (15.3) |
Fair Value of Plan Assets as of December 31, |  | $ | 533.7 |  |  | $ | 681.5 |  |  | $ | 190.5 |  |  | $ | 248.7 |
Funded Status as of December 31, |  | $ | 66.9 |  |  | $ | 69.4 |  |  | $ | 88.6 |  |  | $ | 130.1 |
OPCo |  | Pension Plans |  | OPEB
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Change in Benefit Obligation |  | (in millions)
Benefit Obligation as of January 1, |  | $ | 470.7 |  |  | $ | 510.3 |  |  | $ | 104.9 |  |  | $ | 126.4 |
Service Cost |  | 11.2 |  |  | 11.4 |  |  | 0.6 |  |  | 0.8 |
Interest Cost |  | 13.3 |  |  | 12.5 |  |  | 3.0 |  |  | 3.0 |
Actuarial Gain |  | (97.9) |  |  | (24.1) |  |  | (8.9) |  |  | (15.6) |
Plan Amendments |  | — |  |  | — |  |  | — |  |  | (0.6) |
Benefit Payments |  | (33.7) |  |  | (39.4) |  |  | (15.5) |  |  | (13.6) |
Participant Contributions |  | — |  |  | — |  |  | 4.8 |  |  | 4.5 |
Benefit Obligation as of December 31, |  | $ | 363.6 |  |  | $ | 470.7 |  |  | $ | 88.9 |  |  | $ | 104.9 |
Change in Fair Value of Plan Assets |  |  |  |  |  |  |  |
Fair Value of Plan Assets as of January 1, |  | $ | 524.8 |  |  | $ | 543.1 |  |  | $ | 220.0 |  |  | $ | 213.0 |
Actual Gain (Loss) on Plan Assets |  | (84.8) |  |  | 21.1 |  |  | (43.1) |  |  | 16.1 |
Company Contributions |  | 0.1 |  |  | — |  |  | — |  |  | — |
Participant Contributions |  | — |  |  | — |  |  | 4.8 |  |  | 4.5 |
Benefit Payments |  | (33.7) |  |  | (39.4) |  |  | (15.5) |  |  | (13.6) |
Fair Value of Plan Assets as of December 31, |  | $ | 406.4 |  |  | $ | 524.8 |  |  | $ | 166.2 |  |  | $ | 220.0 |
Funded Status as of December 31, |  | $ | 42.8 |  |  | $ | 54.1 |  |  | $ | 77.3 |  |  | $ | 115.1 |
PSO |  | Pension Plans |  | OPEB
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Change in Benefit Obligation |  | (in millions)
Benefit Obligation as of January 1, |  | $ | 252.6 |  |  | $ | 279.9 |  |  | $ | 54.4 |  |  | $ | 64.0 |
Service Cost |  | 7.4 |  |  | 8.0 |  |  | 0.4 |  |  | 0.6 |
Interest Cost |  | 7.0 |  |  | 6.7 |  |  | 1.5 |  |  | 1.6 |
Actuarial Gain |  | (52.9) |  |  | (17.2) |  |  | (5.2) |  |  | (6.8) |
Plan Amendments |  | — |  |  | — |  |  | — |  |  | (0.3) |
Benefit Payments |  | (21.8) |  |  | (24.8) |  |  | (7.9) |  |  | (7.0) |
Participant Contributions |  | — |  |  | — |  |  | 2.5 |  |  | 2.3 |
Benefit Obligation as of December 31, |  | $ | 192.3 |  |  | $ | 252.6 |  |  | $ | 45.7 |  |  | $ | 54.4 |
Change in Fair Value of Plan Assets |  |  |  |  |  |  |  |
Fair Value of Plan Assets as of January 1, |  | $ | 286.2 |  |  | $ | 299.8 |  |  | $ | 114.0 |  |  | $ | 107.8 |
Actual Gain (Loss) on Plan Assets |  | (46.0) |  |  | 11.1 |  |  | (23.2) |  |  | 10.9 |
Company Contributions |  | 0.1 |  |  | 0.1 |  |  | — |  |  | — |
Participant Contributions |  | — |  |  | — |  |  | 2.5 |  |  | 2.3 |
Benefit Payments |  | (21.8) |  |  | (24.8) |  |  | (7.9) |  |  | (7.0) |
Fair Value of Plan Assets as of December 31, |  | $ | 218.5 |  |  | $ | 286.2 |  |  | $ | 85.4 |  |  | $ | 114.0 |
Funded Status as of December 31, |  | $ | 26.2 |  |  | $ | 33.6 |  |  | $ | 39.7 |  |  | $ | 59.6 |
SWEPCo |  | Pension Plans |  | OPEB
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Change in Benefit Obligation |  | (in millions)
Benefit Obligation as of January 1, |  | $ | 317.7 |  |  | $ | 334.5 |  |  | $ | 65.2 |  |  | $ | 77.1 |
Service Cost |  | 10.6 |  |  | 11.2 |  |  | 0.6 |  |  | 0.8 |
Interest Cost |  | 9.1 |  |  | 8.5 |  |  | 1.8 |  |  | 1.9 |
Actuarial Gain |  | (57.9) |  |  | (3.5) |  |  | (6.6) |  |  | (9.2) |
Plan Amendments |  | — |  |  | — |  |  | — |  |  | (0.4) |
Benefit Payments |  | (28.8) |  |  | (33.0) |  |  | (8.8) |  |  | (7.6) |
Participant Contributions |  | — |  |  | — |  |  | 2.9 |  |  | 2.6 |
Benefit Obligation as of December 31, |  | $ | 250.7 |  |  | $ | 317.7 |  |  | $ | 55.1 |  |  | $ | 65.2 |
Change in Fair Value of Plan Assets |  |  |  |  |  |  |  |
Fair Value of Plan Assets as of January 1, |  | $ | 308.3 |  |  | $ | 326.9 |  |  | $ | 136.6 |  |  | $ | 129.9 |
Actual Gain (Loss) on Plan Assets |  | (48.3) |  |  | 14.3 |  |  | (27.7) |  |  | 11.7 |
Company Contributions |  | 0.1 |  |  | 0.1 |  |  | — |  |  | — |
Participant Contributions |  | — |  |  | — |  |  | 2.9 |  |  | 2.6 |
Benefit Payments |  | (28.8) |  |  | (33.0) |  |  | (8.8) |  |  | (7.6) |
Fair Value of Plan Assets as of December 31, |  | $ | 231.3 |  |  | $ | 308.3 |  |  | $ | 103.0 |  |  | $ | 136.6 |
Funded (Underfunded) Status as of December 31, |  | $ | (19.4) |  |  | $ | (9.4) |  |  | $ | 47.9 |  |  | $ | 71.4 |
Benefit Amounts Recognized on the Balance Sheets |
|  | Pension Plans |  | OPEB
|  | December 31,
AEP |  | 2022 |  | 2021 |  | 2022 |  | 2021
|  | (in millions)
Deferred Charges and Other Noncurrent Assets – Prepaid Benefit Costs |  | $ | 113.4 |  |  | $ | 244.3 |  |  | $ | 699.5 |  |  | $ | 1,040.8 |
Other Current Liabilities – Accrued Short-term Benefit Liability |  | (6.3) |  |  | (7.6) |  |  | (2.5) |  |  | (2.7) |
Employee Benefits and Pension Obligations – Accrued Long-term Benefit Liability |  | (55.1) |  |  | (70.8) |  |  | (20.3) |  |  | (35.1) |
Funded Status |  | $ | 52.0 |  |  | $ | 165.9 |  |  | $ | 676.7 |  |  | $ | 1,003.0 |
|  | Pension Plans |  | OPEB
|  | December 31,
AEP Texas |  | 2022 |  | 2021 |  | 2022 |  | 2021
|  | (in millions)
Deferred Charges and Other Noncurrent Assets – Prepaid Benefit Costs |  | $ | 3.7 |  |  | $ | 28.7 |  |  | $ | 59.7 |  |  | $ | 88.3 |
Other Current Liabilities – Accrued Short-term Benefit Liability |  | (0.4) |  |  | (0.3) |  |  | — |  |  | — |
Deferred Credits and Other Noncurrent Liabilities – Accrued Long-term Benefit Liability |  | (2.3) |  |  | (3.3) |  |  | — |  |  | — |
Funded Status |  | $ | 1.0 |  |  | $ | 25.1 |  |  | $ | 59.7 |  |  | $ | 88.3 |
|  | Pension Plans |  | OPEB
|  | December 31,
APCo |  | 2022 |  | 2021 |  | 2022 |  | 2021
|  | (in millions)
Employee Benefits and Pension Assets – Prepaid Benefit Costs |  | $ | 46.6 |  |  | $ | 62.4 |  |  | $ | 106.3 |  |  | $ | 158.1 |
Other Current Liabilities – Accrued Short-term Benefit Liability |  | — |  |  | — |  |  | (1.6) |  |  | (1.8) |
Employee Benefits and Pension Obligations – Accrued Long-term Benefit Liability |  | (0.6) |  |  | (0.8) |  |  | (16.8) |  |  | (21.3) |
Funded Status |  | $ | 46.0 |  |  | $ | 61.6 |  |  | $ | 87.9 |  |  | $ | 135.0 |
|  | Pension Plans |  | OPEB
|  | December 31,
I&M |  | 2022 |  | 2021 |  | 2022 |  | 2021
|  | (in millions)
Deferred Charges and Other Noncurrent Assets – Prepaid Benefit Costs |  | $ | 68.5 |  |  | $ | 71.4 |  |  | $ | 88.6 |  |  | $ | 130.1 |
Other Current Liabilities – Accrued Short-term Benefit Liability |  | (0.1) |  |  | (0.1) |  |  | — |  |  | — |
Deferred Credits and Other Noncurrent Liabilities – Accrued Long-term Benefit Liability |  | (1.5) |  |  | (1.9) |  |  | — |  |  | — |
Funded Status |  | $ | 66.9 |  |  | $ | 69.4 |  |  | $ | 88.6 |  |  | $ | 130.1 |
|  | Pension Plans |  | OPEB
|  | December 31,
OPCo |  | 2022 |  | 2021 |  | 2022 |  | 2021
|  | (in millions)
Deferred Charges and Other Noncurrent Assets – Prepaid Benefit Costs |  | $ | 43.1 |  |  | $ | 54.8 |  |  | $ | 77.3 |  |  | $ | 115.1 |
Deferred Credits and Other Noncurrent Liabilities – Accrued Long-term Benefit Liability |  | (0.3) |  |  | (0.7) |  |  | — |  |  | — |
Funded Status |  | $ | 42.8 |  |  | $ | 54.1 |  |  | $ | 77.3 |  |  | $ | 115.1 |
|  | Pension Plans |  | OPEB
|  | December 31,
PSO |  | 2022 |  | 2021 |  | 2022 |  | 2021
|  | (in millions)
Employee Benefits and Pension Assets – Prepaid Benefit Costs |  | $ | 27.6 |  |  | $ | 35.5 |  |  | $ | 39.7 |  |  | $ | 59.6 |
Other Current Liabilities – Accrued Short-term Benefit Liability |  | (0.1) |  |  | (0.1) |  |  | — |  |  | — |
Deferred Credits and Other Noncurrent Liabilities – Accrued Long-term Benefit Liability |  | (1.3) |  |  | (1.8) |  |  | — |  |  | — |
Funded Status |  | $ | 26.2 |  |  | $ | 33.6 |  |  | $ | 39.7 |  |  | $ | 59.6 |
|  | Pension Plans |  | OPEB
|  | December 31,
SWEPCo |  | 2022 |  | 2021 |  | 2022 |  | 2021
|  | (in millions)
Deferred Charges and Other Noncurrent Assets – Prepaid Benefit Costs |  | $ | — |  |  | $ | — |  |  | $ | 47.9 |  |  | $ | 71.4 |
Other Current Liabilities – Accrued Short-term Benefit Liability |  | (0.1) |  |  | (0.1) |  |  | — |  |  | — |
Employee Benefits and Pension Obligations – Accrued Long-term Benefit Liability |  | (19.3) |  |  | (9.3) |  |  | — |  |  | — |
Funded (Underfunded) Status |  | $ | (19.4) |  |  | $ | (9.4) |  |  | $ | 47.9 |  |  | $ | 71.4 |
Amounts Included in AOCI and Regulatory Assets |
AEP |  | Pension Plans |  | OPEB
|  | December 31,
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Components |  | (in millions)
Net Actuarial (Gain) Loss |  | $ | 935.6 |  |  | $ | 894.7 |  |  | $ | 300.0 |  |  | $ | (103.6) |
Prior Service Cost (Credit) |  | 0.2 |  |  | 0.2 |  |  | (90.5) |  |  | (161.9) |
Recorded as |  |  |  |  |  |  |  |
Regulatory Assets |  | $ | 841.8 |  |  | $ | 878.0 |  |  | $ | 126.0 |  |  | $ | (195.1) |
Deferred Income Taxes |  | 19.9 |  |  | 3.6 |  |  | 17.5 |  |  | (14.7) |
Net of Tax AOCI |  | 74.1 |  |  | 13.3 |  |  | 66.0 |  |  | (55.7) |
AEP Texas |  | Pension Plans |  | OPEB
|  | December 31,
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Components |  | (in millions)
Net Actuarial (Gain) Loss |  | $ | 161.9 |  |  | $ | 144.7 |  |  | $ | 29.7 |  |  | $ | (5.2) |
Prior Service Credit |  | — |  |  | — |  |  | (7.6) |  |  | (13.7) |
Recorded as |  |  |  |  |  |  |  |
Regulatory Assets |  | $ | 151.2 |  |  | $ | 136.7 |  |  | $ | 22.0 |  |  | $ | (17.7) |
Deferred Income Taxes |  | 2.4 |  |  | 1.8 |  |  | 0.1 |  |  | (0.2) |
Net of Tax AOCI |  | 8.3 |  |  | 6.2 |  |  | — |  |  | (1.0) |
APCo |  | Pension Plans |  | OPEB
|  | December 31,
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Components |  | (in millions)
Net Actuarial (Gain) Loss |  | $ | 95.6 |  |  | $ | 83.9 |  |  | $ | 40.5 |  |  | $ | (18.9) |
Prior Service Credit |  | — |  |  | — |  |  | (13.4) |  |  | (23.8) |
Recorded as |  |  |  |  |  |  |  |
Regulatory Assets |  | $ | 93.6 |  |  | $ | 82.5 |  |  | $ | 14.7 |  |  | $ | (19.8) |
Deferred Income Taxes |  | 0.4 |  |  | 0.3 |  |  | 2.5 |  |  | (4.9) |
Net of Tax AOCI |  | 1.6 |  |  | 1.1 |  |  | 9.9 |  |  | (18.0) |
I&M |  | Pension Plans |  | OPEB
|  | December 31,
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Components |  | (in millions)
Net Actuarial (Gain) Loss |  | $ | (6.9) |  |  | $ | (1.6) |  |  | $ | 40.2 |  |  | $ | (10.7) |
Prior Service Credit |  | — |  |  | — |  |  | (12.4) |  |  | (22.1) |
Recorded as |  |  |  |  |  |  |  |
Regulatory Assets/Liabilities (a) |  | $ | 4.8 |  |  | $ | 3.1 |  |  | $ | 22.1 |  |  | $ | (30.7) |
Deferred Income Taxes |  | (2.4) |  |  | (1.0) |  |  | 1.2 |  |  | (0.4) |
Net of Tax AOCI |  | (9.3) |  |  | (3.7) |  |  | 4.5 |  |  | (1.7) |
(a)Recorded as a Regulatory Asset as of December 31, 2022 and recorded as a Regulatory Liability as of December 31, 2021.
OPCo |  | Pension Plans |  | OPEB
|  | December 31,
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Components |  | (in millions)
Net Actuarial (Gain) Loss |  | $ | 124.3 |  |  | $ | 118.1 |  |  | $ | 27.6 |  |  | $ | (18.5) |
Prior Service Credit |  | — |  |  | — |  |  | (9.2) |  |  | (16.3) |
Recorded as |  |  |  |  |  |  |  |
Regulatory Assets |  | $ | 124.3 |  |  | $ | 118.1 |  |  | $ | 18.4 |  |  | $ | (34.8) |
PSO |  | Pension Plans |  | OPEB
|  | December 31,
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Components |  | (in millions)
Net Actuarial (Gain) Loss |  | $ | 38.8 |  |  | $ | 35.0 |  |  | $ | 22.0 |  |  | $ | (2.1) |
Prior Service Credit |  | — |  |  | — |  |  | (5.6) |  |  | (10.0) |
Recorded as |  |  |  |  |  |  |  |
Regulatory Assets |  | $ | 38.8 |  |  | $ | 35.0 |  |  | $ | 16.4 |  |  | $ | (12.1) |
SWEPCo |  | Pension Plans |  | OPEB
|  | December 31,
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Components |  | (in millions)
Net Actuarial (Gain) Loss |  | $ | 77.6 |  |  | $ | 76.4 |  |  | $ | 25.0 |  |  | $ | (3.5) |
Prior Service Credit |  | — |  |  | — |  |  | (7.0) |  |  | (12.3) |
Recorded as |  |  |  |  |  |  |  |
Regulatory Assets |  | $ | 77.6 |  |  | $ | 76.4 |  |  | $ | 11.2 |  |  | $ | (8.9) |
Deferred Income Taxes |  | — |  |  | — |  |  | 1.5 |  |  | (1.4) |
Net of Tax AOCI |  | — |  |  | — |  |  | 5.3 |  |  | (5.5) |
Components of Change in Amounts Included in AOCI and Regulatory Assets |
AEP |  | Pension Plans |  | OPEB
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Components |  | (in millions)
Actuarial (Gain) Loss During the Year |  | $ | 103.9 |  |  | $ | (183.4) |  |  | $ | 403.6 |  |  | $ | (205.5) |
Amortization of Actuarial Loss |  | (63.0) |  |  | (101.5) |  |  | — |  |  | — |
Prior Service Credit |  | — |  |  | — |  |  | — |  |  | (5.5) |
Amortization of Prior Service Credit |  | — |  |  | — |  |  | 71.4 |  |  | 70.9 |
Change for the Year Ended December 31, |  | $ | 40.9 |  |  | $ | (284.9) |  |  | $ | 475.0 |  |  | $ | (140.1) |
AEP Texas |  | Pension Plans |  | OPEB
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Components |  | (in millions)
Actuarial (Gain) Loss During the Year |  | $ | 22.4 |  |  | $ | (7.5) |  |  | $ | 34.9 |  |  | $ | (17.5) |
Amortization of Actuarial Loss |  | (5.2) |  |  | (8.3) |  |  | — |  |  | — |
Prior Service Credit |  | — |  |  | — |  |  | — |  |  | (0.4) |
Amortization of Prior Service Credit |  | — |  |  | — |  |  | 6.1 |  |  | 6.0 |
Change for the Year Ended December 31, |  | $ | 17.2 |  |  | $ | (15.8) |  |  | $ | 41.0 |  |  | $ | (11.9) |
APCo |  | Pension Plans |  | OPEB
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Components |  | (in millions)
Actuarial (Gain) Loss During the Year |  | $ | 19.1 |  |  | $ | (30.4) |  |  | $ | 59.4 |  |  | $ | (30.0) |
Amortization of Actuarial Loss |  | (7.4) |  |  | (12.0) |  |  | — |  |  | — |
Prior Service Credit |  | — |  |  | — |  |  | — |  |  | (0.9) |
Amortization of Prior Service Credit |  | — |  |  | — |  |  | 10.4 |  |  | 10.3 |
Change for the Year Ended December 31, |  | $ | 11.7 |  |  | $ | (42.4) |  |  | $ | 69.8 |  |  | $ | (20.6) |
I&M |  | Pension Plans |  | OPEB
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Components |  | (in millions)
Actuarial (Gain) Loss During the Year |  | $ | 1.8 |  |  | $ | (29.4) |  |  | $ | 50.9 |  |  | $ | (26.3) |
Amortization of Actuarial Loss |  | (7.1) |  |  | (11.7) |  |  | — |  |  | — |
Prior Service Credit |  | — |  |  | — |  |  | — |  |  | (0.7) |
Amortization of Prior Service Credit |  | — |  |  | — |  |  | 9.7 |  |  | 9.6 |
Change for the Year Ended December 31, |  | $ | (5.3) |  |  | $ | (41.1) |  |  | $ | 60.6 |  |  | $ | (17.4) |
OPCo |  | Pension Plans |  | OPEB
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Components |  | (in millions)
Actuarial (Gain) Loss During the Year |  | $ | 11.7 |  |  | $ | (22.8) |  |  | $ | 46.1 |  |  | $ | (22.1) |
Amortization of Actuarial Loss |  | (5.5) |  |  | (9.1) |  |  | — |  |  | — |
Prior Service Credit |  | — |  |  | — |  |  | — |  |  | (0.6) |
Amortization of Prior Service Credit |  | — |  |  | — |  |  | 7.1 |  |  | 7.2 |
Change for the Year Ended December 31, |  | $ | 6.2 |  |  | $ | (31.9) |  |  | $ | 53.2 |  |  | $ | (15.5) |
PSO |  | Pension Plans |  | OPEB
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Components |  | (in millions)
Actuarial (Gain) Loss During the Year |  | $ | 6.7 |  |  | $ | (16.0) |  |  | $ | 24.1 |  |  | $ | (12.6) |
Amortization of Actuarial Loss |  | (2.9) |  |  | (4.9) |  |  | — |  |  | — |
Prior Service Credit |  | — |  |  | — |  |  | — |  |  | (0.3) |
Amortization of Prior Service Credit |  | — |  |  | — |  |  | 4.4 |  |  | 4.4 |
Change for the Year Ended December 31, |  | $ | 3.8 |  |  | $ | (20.9) |  |  | $ | 28.5 |  |  | $ | (8.5) |
SWEPCo |  | Pension Plans |  | OPEB
|  | 2022 |  | 2021 |  | 2022 |  | 2021
Components |  | (in millions)
Actuarial (Gain) Loss During the Year |  | $ | 5.0 |  |  | $ | (4.3) |  |  | $ | 28.5 |  |  | $ | (15.0) |
Amortization of Actuarial Loss |  | (3.8) |  |  | (6.2) |  |  | — |  |  | — |
Prior Service Credit |  | — |  |  | — |  |  | — |  |  | (0.4) |
Amortization of Prior Service Credit |  | — |  |  | — |  |  | 5.3 |  |  | 5.3 |
Change for the Year Ended December 31, |  | $ | 1.2 |  |  | $ | (10.5) |  |  | $ | 33.8 |  |  | $ | (10.1) |
Allocated Assets of Investments |
|  | Pension Plan |  | OPEB
|  | December 31,
Company |  | 2022 |  | 2021 |  | 2022 |  | 2021
AEP Texas |  | 8.1 | % |  | 8.3 | % |  | 8.3 | % |  | 8.3 | %
APCo |  | 12.9 | % |  | 12.8 | % |  | 14.8 | % |  | 14.8 | %
I&M |  | 12.9 | % |  | 12.7 | % |  | 12.3 | % |  | 12.2 | %
OPCo |  | 9.9 | % |  | 9.8 | % |  | 10.7 | % |  | 10.8 | %
PSO |  | 5.3 | % |  | 5.3 | % |  | 5.5 | % |  | 5.6 | %
SWEPCo |  | 5.6 | % |  | 5.8 | % |  | 6.6 | % |  | 6.7 | %
Accumulated Benefit Obligation |
Accumulated Benefit Obligation |  | AEP |  | AEP Texas |  | APCo |  | I&M |  | OPCo |  | PSO |  | SWEPCo
|  | (in millions)
Qualified Pension Plan |  | $ | 3,827.4 |  |  | $ | 315.4 |  |  | $ | 470.1 |  |  | $ | 443.8 |  |  | $ | 344.1 |  |  | $ | 179.1 |  |  | $ | 234.0 |
Nonqualified Pension Plans |  | 55.6 |  |  | 2.5 |  |  | 0.3 |  |  | 1.2 |  |  | 0.1 |  |  | 1.2 |  |  | 1.1 |
Total as of December 31, 2022 |  | $ | 3,883.0 |  |  | $ | 317.9 |  |  | $ | 470.4 |  |  | $ | 445.0 |  |  | $ | 344.2 |  |  | $ | 180.3 |  |  | $ | 235.1 |
Accumulated Benefit Obligation |  | AEP |  | AEP Texas |  | APCo |  | I&M |  | OPCo |  | PSO |  | SWEPCo
|  | (in millions)
Qualified Pension Plan |  | $ | 4,822.5 |  |  | $ | 391.4 |  |  | $ | 597.0 |  |  | $ | 575.2 |  |  | $ | 440.0 |  |  | $ | 232.1 |  |  | $ | 291.4 |
Nonqualified Pension Plans |  | 69.7 |  |  | 3.3 |  |  | 0.4 |  |  | 1.2 |  |  | 0.3 |  |  | 1.5 |  |  | 1.3 |
Total as of December 31, 2021 |  | $ | 4,892.2 |  |  | $ | 394.7 |  |  | $ | 597.4 |  |  | $ | 576.4 |  |  | $ | 440.3 |  |  | $ | 233.6 |  |  | $ | 292.7 |
Underfunded Projected Benefit Obligation |
| AEP |  | AEP Texas |  | APCo |  | I&M |  | OPCo |  | PSO |  | SWEPCo
| (in millions)
Projected Benefit Obligation | $ | 61.5 |  |  | $ | 2.7 |  |  | $ | 0.6 |  |  | $ | 1.6 |  |  | $ | 0.3 |  |  | $ | 1.5 |  |  | $ | 250.7 |
Fair Value of Plan Assets | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 231.3 |
Underfunded Projected Benefit Obligation as of December 31, 2022 | $ | (61.5) |  |  | $ | (2.7) |  |  | $ | (0.6) |  |  | $ | (1.6) |  |  | $ | (0.3) |  |  | $ | (1.5) |  |  | $ | (19.4) |
| AEP |  | AEP Texas |  | APCo |  | I&M |  | OPCo |  | PSO |  | SWEPCo
| (in millions)
Projected Benefit Obligation | $ | 78.4 |  |  | $ | 3.6 |  |  | $ | 0.8 |  |  | $ | 1.9 |  |  | $ | 0.7 |  |  | $ | 1.9 |  |  | $ | 317.7 |
Fair Value of Plan Assets | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 308.3 |
Underfunded Projected Benefit Obligation as of December 31, 2021 | $ | (78.4) |  |  | $ | (3.6) |  |  | $ | (0.8) |  |  | $ | (1.9) |  |  | $ | (0.7) |  |  | $ | (1.9) |  |  | $ | (9.4) |
Underfunded Accumulated Benefit Obligation |
| AEP |  | AEP Texas |  | APCo |  | I&M |  | OPCo |  | PSO |  | SWEPCo
| (in millions)
Accumulated Benefit Obligation | $ | 55.6 |  |  | $ | 2.5 |  |  | $ | 0.3 |  |  | $ | 1.2 |  |  | $ | 0.1 |  |  | $ | 1.2 |  |  | $ | 235.1 |
Fair Value of Plan Assets | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 231.3 |
Underfunded Accumulated Benefit Obligation as of December 31, 2022 | $ | (55.6) |  |  | $ | (2.5) |  |  | $ | (0.3) |  |  | $ | (1.2) |  |  | $ | (0.1) |  |  | $ | (1.2) |  |  | $ | (3.8) |
| AEP |  | AEP Texas |  | APCo |  | I&M |  | OPCo |  | PSO |  | SWEPCo
| (in millions)
Accumulated Benefit Obligation | $ | 69.7 |  |  | $ | 3.3 |  |  | $ | 0.4 |  |  | $ | 1.2 |  |  | $ | 0.3 |  |  | $ | 1.5 |  |  | $ | 1.3 |
Fair Value of Plan Assets | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Underfunded Accumulated Benefit Obligation as of December 31, 2021 | $ | (69.7) |  |  | $ | (3.3) |  |  | $ | (0.4) |  |  | $ | (1.2) |  |  | $ | (0.3) |  |  | $ | (1.5) |  |  | $ | (1.3) |
Estimated Contributions and Payments to the Pension and OPEB Plans |
Company |  | Pension Plans |  | OPEB
|  | (in millions)
AEP |  | $ | 6.3 |  |  | $ | 3.1 |
AEP Texas |  | 0.4 |  |  | 0.1 |
APCo |  | — |  |  | 1.6 |
I&M |  | 0.1 |  |  | — |
PSO |  | 0.1 |  |  | — |
SWEPCo |  | 0.1 |  |  | — |
Estimated Payments Expected to be Made by the Pension and OPEB Plans |
Pension Plans |  | AEP |  | AEP Texas |  | APCo |  | I&M |  | OPCo |  | PSO |  | SWEPCo
|  | (in millions)
2023 |  | $ | 369.0 |  |  | $ | 35.4 |  |  | $ | 43.7 |  |  | $ | 38.1 |  |  | $ | 32.3 |  |  | $ | 19.2 |  |  | $ | 24.2 |
2024 |  | 373.6 |  |  | 36.3 |  |  | 43.6 |  |  | 39.8 |  |  | 31.9 |  |  | 18.9 |  |  | 25.1 |
2025 |  | 368.8 |  |  | 35.2 |  |  | 42.5 |  |  | 40.7 |  |  | 32.4 |  |  | 19.0 |  |  | 25.3 |
2026 |  | 369.6 |  |  | 35.0 |  |  | 43.0 |  |  | 40.4 |  |  | 32.0 |  |  | 19.2 |  |  | 25.5 |
2027 |  | 364.3 |  |  | 32.6 |  |  | 41.8 |  |  | 41.0 |  |  | 31.6 |  |  | 18.4 |  |  | 25.4 |
Years 2028 to 2032, in Total |  | 1,702.3 |  |  | 138.9 |  |  | 202.1 |  |  | 196.4 |  |  | 146.0 |  |  | 81.1 |  |  | 107.9 |
OPEB Benefit Payments |  | AEP |  | AEP Texas |  | APCo |  | I&M |  | OPCo |  | PSO |  | SWEPCo
|  | (in millions)
2023 |  | $ | 116.0 |  |  | $ | 9.1 |  |  | $ | 19.0 |  |  | $ | 14.9 |  |  | $ | 12.6 |  |  | $ | 6.7 |  |  | $ | 7.5 |
2024 |  | 117.6 |  |  | 9.5 |  |  | 19.3 |  |  | 15.0 |  |  | 12.6 |  |  | 6.9 |  |  | 7.8 |
2025 |  | 126.9 |  |  | 10.4 |  |  | 20.5 |  |  | 16.1 |  |  | 13.5 |  |  | 7.4 |  |  | 8.5 |
2026 |  | 127.4 |  |  | 10.6 |  |  | 20.4 |  |  | 16.3 |  |  | 13.4 |  |  | 7.3 |  |  | 8.6 |
2027 |  | 126.8 |  |  | 10.6 |  |  | 20.3 |  |  | 16.1 |  |  | 13.3 |  |  | 7.1 |  |  | 8.5 |
Years 2028 to 2032, in Total |  | 604.0 |  |  | 48.5 |  |  | 95.8 |  |  | 75.1 |  |  | 62.3 |  |  | 32.2 |  |  | 41.2 |
OPEB Medicare Subsidy Receipts |  | AEP |  | AEP Texas |  | APCo |  | I&M |  | OPCo |  | PSO |  | SWEPCo
|  | (in millions)
2023 |  | $ | 0.2 |  |  | $ | — |  |  | $ | 0.1 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
2024 |  | 0.3 |  |  | — |  |  | 0.1 |  |  | — |  |  | — |  |  | — |  |  | — |
2025 |  | 0.3 |  |  | — |  |  | 0.1 |  |  | — |  |  | — |  |  | — |  |  | — |
2026 |  | 0.3 |  |  | — |  |  | 0.1 |  |  | — |  |  | — |  |  | — |  |  | — |
2027 |  | 0.3 |  |  | — |  |  | 0.1 |  |  | — |  |  | — |  |  | — |  |  | — |
Years 2028 to 2032, in Total |  | 1.6 |  |  | — |  |  | 0.5 |  |  | — |  |  | — |  |  | — |  |  | — |
Components of Net Periodic Benefit Cost |
AEP | Pension Plans |  | OPEB
| Years Ended December 31,
| 2022 |  | 2021 |  | 2020 |  | 2022 |  | 2021 |  | 2020
| (in millions)
Service Cost | $ | 123.1 |  |  | $ | 129.2 |  |  | $ | 111.9 |  |  | $ | 7.4 |  |  | $ | 9.5 |  |  | $ | 10.0 |
Interest Cost | 148.2 |  |  | 137.2 |  |  | 167.9 |  |  | 29.2 |  |  | 30.5 |  |  | 39.8 |
Expected Return on Plan Assets | (253.4) |  |  | (229.7) |  |  | (264.9) |  |  | (110.0) |  |  | (91.1) |  |  | (95.6) |
Amortization of Prior Service Credit | — |  |  | — |  |  | — |  |  | (71.4) |  |  | (70.9) |  |  | (69.8) |
Amortization of Net Actuarial Loss | 63.0 |  |  | 101.5 |  |  | 93.7 |  |  | — |  |  | — |  |  | 5.9 |
Settlements | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Net Periodic Benefit Cost (Credit) | 80.9 |  |  | 138.2 |  |  | 108.6 |  |  | (144.8) |  |  | (122.0) |  |  | (109.7) |
Capitalized Portion | (53.8) |  |  | (55.7) |  |  | (47.0) |  |  | (3.2) |  |  | (4.1) |  |  | (4.2) |
Net Periodic Benefit Cost (Credit) Recognized in Expense | $ | 27.1 |  |  | $ | 82.5 |  |  | $ | 61.6 |  |  | $ | (148.0) |  |  | $ | (126.1) |  |  | $ | (113.9) |
AEP Texas | Pension Plans |  | OPEB
| Years Ended December 31,
| 2022 |  | 2021 |  | 2020 |  | 2022 |  | 2021 |  | 2020
| (in millions)
Service Cost | $ | 11.1 |  |  | $ | 11.8 |  |  | $ | 10.0 |  |  | $ | 0.5 |  |  | $ | 0.7 |  |  | $ | 0.8 |
Interest Cost | 12.1 |  |  | 11.2 |  |  | 13.9 |  |  | 2.2 |  |  | 2.4 |  |  | 3.2 |
Expected Return on Plan Assets | (21.0) |  |  | (19.5) |  |  | (22.7) |  |  | (9.1) |  |  | (7.5) |  |  | (8.0) |
Amortization of Prior Service Credit | — |  |  | — |  |  | — |  |  | (6.1) |  |  | (6.0) |  |  | (5.9) |
Amortization of Net Actuarial Loss | 5.2 |  |  | 8.3 |  |  | 7.8 |  |  | — |  |  | — |  |  | 0.5 |
Net Periodic Benefit Cost (Credit) | 7.4 |  |  | 11.8 |  |  | 9.0 |  |  | (12.5) |  |  | (10.4) |  |  | (9.4) |
Capitalized Portion | (6.2) |  |  | (6.6) |  |  | (5.5) |  |  | (0.3) |  |  | (0.4) |  |  | (0.4) |
Net Periodic Benefit Cost (Credit) Recognized in Expense | $ | 1.2 |  |  | $ | 5.2 |  |  | $ | 3.5 |  |  | $ | (12.8) |  |  | $ | (10.8) |  |  | $ | (9.8) |
APCo | Pension Plans |  | OPEB
| Years Ended December 31,
| 2022 |  | 2021 |  | 2020 |  | 2022 |  | 2021 |  | 2020
| (in millions)
Service Cost | $ | 11.4 |  |  | $ | 11.9 |  |  | $ | 10.5 |  |  | $ | 0.8 |  |  | $ | 1.0 |  |  | $ | 1.0 |
Interest Cost | 17.5 |  |  | 16.4 |  |  | 20.3 |  |  | 4.7 |  |  | 4.9 |  |  | 6.6 |
Expected Return on Plan Assets | (32.3) |  |  | (29.1) |  |  | (33.6) |  |  | (16.3) |  |  | (13.5) |  |  | (14.4) |
Amortization of Prior Service Credit | — |  |  | — |  |  | — |  |  | (10.4) |  |  | (10.3) |  |  | (10.2) |
Amortization of Net Actuarial Loss | 7.4 |  |  | 12.0 |  |  | 11.2 |  |  | — |  |  | — |  |  | 0.9 |
Net Periodic Benefit Cost (Credit) | 4.0 |  |  | 11.2 |  |  | 8.4 |  |  | (21.2) |  |  | (17.9) |  |  | (16.1) |
Capitalized Portion | (5.0) |  |  | (5.2) |  |  | (4.5) |  |  | (0.4) |  |  | (0.4) |  |  | (0.4) |
Net Periodic Benefit Cost (Credit) Recognized in Expense | $ | (1.0) |  |  | $ | 6.0 |  |  | $ | 3.9 |  |  | $ | (21.6) |  |  | $ | (18.3) |  |  | $ | (16.5) |
I&M | Pension Plans |  | OPEB
| Years Ended December 31,
| 2022 |  | 2021 |  | 2020 |  | 2022 |  | 2021 |  | 2020
| (in millions)
Service Cost | $ | 16.2 |  |  | $ | 17.5 |  |  | $ | 15.4 |  |  | $ | 0.9 |  |  | $ | 1.3 |  |  | $ | 1.4 |
Interest Cost | 17.0 |  |  | 16.2 |  |  | 19.7 |  |  | 3.4 |  |  | 3.5 |  |  | 4.7 |
Expected Return on Plan Assets | (32.4) |  |  | (28.9) |  |  | (33.3) |  |  | (13.7) |  |  | (11.1) |  |  | (11.7) |
Amortization of Prior Service Credit | — |  |  | — |  |  | — |  |  | (9.7) |  |  | (9.6) |  |  | (9.5) |
Amortization of Net Actuarial Loss | 7.1 |  |  | 11.7 |  |  | 10.8 |  |  | — |  |  | — |  |  | 0.7 |
Net Periodic Benefit Cost (Credit) | 7.9 |  |  | 16.5 |  |  | 12.6 |  |  | (19.1) |  |  | (15.9) |  |  | (14.4) |
Capitalized Portion | (4.6) |  |  | (4.9) |  |  | (4.3) |  |  | (0.3) |  |  | (0.4) |  |  | (0.4) |
Net Periodic Benefit Cost (Credit) Recognized in Expense | $ | 3.3 |  |  | $ | 11.6 |  |  | $ | 8.3 |  |  | $ | (19.4) |  |  | $ | (16.3) |  |  | $ | (14.8) |
OPCo | Pension Plans |  | OPEB
| Years Ended December 31,
| 2022 |  | 2021 |  | 2020 |  | 2022 |  | 2021 |  | 2020
| (in millions)
Service Cost | $ | 11.2 |  |  | $ | 11.4 |  |  | $ | 9.7 |  |  | $ | 0.6 |  |  | $ | 0.8 |  |  | $ | 0.9 |
Interest Cost | 13.3 |  |  | 12.5 |  |  | 15.4 |  |  | 3.0 |  |  | 3.0 |  |  | 4.2 |
Expected Return on Plan Assets | (24.8) |  |  | (22.3) |  |  | (26.3) |  |  | (12.0) |  |  | (9.7) |  |  | (10.5) |
Amortization of Prior Service Credit | — |  |  | — |  |  | — |  |  | (7.1) |  |  | (7.2) |  |  | (7.0) |
Amortization of Net Actuarial Loss | 5.5 |  |  | 9.1 |  |  | 8.5 |  |  | — |  |  | — |  |  | 0.7 |
Net Periodic Benefit Cost (Credit) | 5.2 |  |  | 10.7 |  |  | 7.3 |  |  | (15.5) |  |  | (13.1) |  |  | (11.7) |
Capitalized Portion | (6.1) |  |  | (6.2) |  |  | (5.0) |  |  | (0.3) |  |  | (0.4) |  |  | (0.5) |
Net Periodic Benefit Cost (Credit) Recognized in Expense | $ | (0.9) |  |  | $ | 4.5 |  |  | $ | 2.3 |  |  | $ | (15.8) |  |  | $ | (13.5) |  |  | $ | (12.2) |
PSO | Pension Plans |  | OPEB
| Years Ended December 31,
| 2022 |  | 2021 |  | 2020 |  | 2022 |  | 2021 |  | 2020
| (in millions)
Service Cost | $ | 7.4 |  |  | $ | 8.0 |  |  | $ | 7.3 |  |  | $ | 0.4 |  |  | $ | 0.6 |  |  | $ | 0.7 |
Interest Cost | 7.0 |  |  | 6.7 |  |  | 8.5 |  |  | 1.5 |  |  | 1.6 |  |  | 2.1 |
Expected Return on Plan Assets | (13.4) |  |  | (12.3) |  |  | (14.5) |  |  | (6.1) |  |  | (5.0) |  |  | (5.2) |
Amortization of Prior Service Credit | — |  |  | — |  |  | — |  |  | (4.4) |  |  | (4.4) |  |  | (4.4) |
Amortization of Net Actuarial Loss | 2.9 |  |  | 4.9 |  |  | 4.7 |  |  | — |  |  | — |  |  | 0.3 |
Net Periodic Benefit Cost (Credit) | 3.9 |  |  | 7.3 |  |  | 6.0 |  |  | (8.6) |  |  | (7.2) |  |  | (6.5) |
Capitalized Portion | (3.2) |  |  | (3.4) |  |  | (2.8) |  |  | (0.2) |  |  | (0.3) |  |  | (0.3) |
Net Periodic Benefit Cost (Credit) Recognized in Expense | $ | 0.7 |  |  | $ | 3.9 |  |  | $ | 3.2 |  |  | $ | (8.8) |  |  | $ | (7.5) |  |  | $ | (6.8) |
SWEPCo | Pension Plans |  | OPEB
| Years Ended December 31,
| 2022 |  | 2021 |  | 2020 |  | 2022 |  | 2021 |  | 2020
| (in millions)
Service Cost | $ | 10.6 |  |  | $ | 11.2 |  |  | $ | 9.9 |  |  | $ | 0.6 |  |  | $ | 0.8 |  |  | $ | 0.8 |
Interest Cost | 9.1 |  |  | 8.5 |  |  | 10.2 |  |  | 1.8 |  |  | 1.9 |  |  | 2.5 |
Expected Return on Plan Assets | (14.6) |  |  | (13.5) |  |  | (15.7) |  |  | (7.3) |  |  | (6.1) |  |  | (6.3) |
Amortization of Prior Service Credit | — |  |  | — |  |  | — |  |  | (5.3) |  |  | (5.3) |  |  | (5.2) |
Amortization of Net Actuarial Loss | 3.8 |  |  | 6.2 |  |  | 5.7 |  |  | — |  |  | — |  |  | 0.4 |
Net Periodic Benefit Cost (Credit) | 8.9 |  |  | 12.4 |  |  | 10.1 |  |  | (10.2) |  |  | (8.7) |  |  | (7.8) |
Capitalized Portion | (4.0) |  |  | (4.1) |  |  | (3.4) |  |  | (0.2) |  |  | (0.3) |  |  | (0.3) |
Net Periodic Benefit Cost (Credit) Recognized in Expense | $ | 4.9 |  |  | $ | 8.3 |  |  | $ | 6.7 |  |  | $ | (10.4) |  |  | $ | (9.0) |  |  | $ | (8.1) |
Cost for Matching Contributions to the Retirement Savings Plans |
|  | Year Ended December 31,
Company |  | 2022 |  | 2021 |  | 2020
|  | (in millions)
AEP |  | $ | 81.9 |  |  | $ | 79.9 |  |  | $ | 81.8 |
AEP Texas |  | 6.5 |  |  | 6.4 |  |  | 6.4 |
APCo |  | 7.8 |  |  | 7.6 |  |  | 7.7 |
I&M |  | 11.1 |  |  | 10.9 |  |  | 11.3 |
OPCo |  | 7.7 |  |  | 7.2 |  |  | 7.3 |
PSO |  | 4.7 |  |  | 4.6 |  |  | 4.9 |
SWEPCo |  | 6.4 |  |  | 6.4 |  |  | 6.7 |
Benefit Obligations [Member] |
Actuarial Assumptions |
|  | Pension Plans |  | OPEB
|  | December 31,
Assumption |  | 2022 |  | 2021 |  | 2022 |  | 2021
Discount Rate |  | 5.50 | % |  | 2.90 | % |  | 5.50 | % |  | 2.90 | %
Interest Crediting Rate |  | 4.25 | % |  | 4.00 | % |  | NA |  | NA
NA Not applicable.
|  | Pension Plans
|  | December 31,
Assumption – Rate of Compensation Increase (a) |  | 2022 |  | 2021
AEP |  | 5.05 | % |  | 5.10 | %
AEP Texas |  | 5.15 | % |  | 5.10 | %
APCo |  | 4.90 | % |  | 4.85 | %
I&M |  | 5.00 | % |  | 5.00 | %
OPCo |  | 5.35 | % |  | 5.30 | %
PSO |  | 5.15 | % |  | 5.10 | %
SWEPCo |  | 5.00 | % |  | 4.95 | %
(a)Rates are for base pay only. In addition, an amount is added to reflect target incentive compensation for exempt employees and overtime and incentive pay for nonexempt employees.
Benefit Costs [Member] |
Actuarial Assumptions |
|  | Pension Plans |  | OPEB
|  | Year Ended December 31,
Assumption |  | 2022 |  | 2021 |  | 2020 |  | 2022 |  | 2021 |  | 2020
Discount Rate |  | 2.90 | % |  | 2.50 | % |  | 3.25 | % |  | 2.90 | % |  | 2.55 | % |  | 3.30 | %
Interest Crediting Rate |  | 4.00 | % |  | 4.00 | % |  | 4.00 | % |  | NA |  | NA |  | NA
Expected Return on Plan Assets |  | 5.25 | % |  | 4.75 | % |  | 5.75 | % |  | 5.50 | % |  | 4.75 | % |  | 5.50 | %
NA Not applicable.
|  | Pension Plans
|  | Year Ended December 31,
Assumption – Rate of Compensation Increase (a) |  | 2022 |  | 2021 |  | 2020
AEP |  | 5.05 | % |  | 5.10 | % |  | 5.00 | %
AEP Texas |  | 5.15 | % |  | 5.10 | % |  | 5.05 | %
APCo |  | 4.90 | % |  | 4.85 | % |  | 4.85 | %
I&M |  | 5.00 | % |  | 5.00 | % |  | 5.00 | %
OPCo |  | 5.35 | % |  | 5.30 | % |  | 5.25 | %
PSO |  | 5.15 | % |  | 5.10 | % |  | 5.05 | %
SWEPCo |  | 5.00 | % |  | 4.95 | % |  | 4.90 | %
(a)Rates are for base pay only. In addition, an amount is added to reflect target incentive compensation for exempt employees and overtime and incentive pay for nonexempt employees.
Pension Plans [Member] |
Assets within Fair Value Hierarchy |
Asset Class |  | Level 1 |  | Level 2 |  | Level 3 |  | Other |  | Total |  | Year End Allocation
|  | (in millions) |  |
Equities (a): |  |  |  |  |  |  |  |  |  |  |  |
Domestic |  | $ | 347.6 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 347.6 |  |  | 8.4 | %
International |  | 398.4 |  |  | — |  |  | — |  |  | — |  |  | 398.4 |  |  | 9.7 | %
Common Collective Trusts (b) |  | — |  |  | — |  |  | — |  |  | 379.9 |  |  | 379.9 |  |  | 9.2 | %
Subtotal – Equities |  | 746.0 |  |  | — |  |  | — |  |  | 379.9 |  |  | 1,125.9 |  |  | 27.3 | %
Fixed Income (a): |  |  |  |  |  |  |  |  |  |  |  |
United States Government and Agency Securities |  | (0.6) |  |  | 1,071.4 |  |  | — |  |  | — |  |  | 1,070.8 |  |  | 26.0 | %
Corporate Debt |  | — |  |  | 891.7 |  |  | — |  |  | — |  |  | 891.7 |  |  | 21.6 | %
Foreign Debt |  | — |  |  | 140.2 |  |  | — |  |  | — |  |  | 140.2 |  |  | 3.4 | %
State and Local Government |  | — |  |  | 37.0 |  |  | — |  |  | — |  |  | 37.0 |  |  | 0.9 | %
Other – Asset Backed |  | — |  |  | 0.8 |  |  | — |  |  | — |  |  | 0.8 |  |  | — | %
Subtotal – Fixed Income |  | (0.6) |  |  | 2,141.1 |  |  | — |  |  | — |  |  | 2,140.5 |  |  | 51.9 | %
Infrastructure (b) |  | — |  |  | — |  |  | — |  |  | 109.2 |  |  | 109.2 |  |  | 2.6 | %
Real Estate (b) |  | — |  |  | — |  |  | — |  |  | 276.9 |  |  | 276.9 |  |  | 6.7 | %
Alternative Investments (b) |  | — |  |  | — |  |  | — |  |  | 319.7 |  |  | 319.7 |  |  | 7.8 | %
Cash and Cash Equivalents (b) |  | — |  |  | 64.9 |  |  | — |  |  | 58.3 |  |  | 123.2 |  |  | 3.0 | %
Other – Pending Transactions and Accrued Income (c) |  | — |  |  | — |  |  | — |  |  | 29.3 |  |  | 29.3 |  |  | 0.7 | %
Total |  | $ | 745.4 |  |  | $ | 2,206.0 |  |  | $ | — |  |  | $ | 1,173.3 |  |  | $ | 4,124.7 |  |  | 100.0 | %
(a)Includes investment securities loaned to borrowers under the securities lending program. See the “Investments Held in Trust for Future Liabilities” section of Note 1 for additional information. (b)Amounts in “Other” column represent investments for which fair value is measured using net asset value per-share. (c)Amounts in “Other” column primarily represent accrued interest, dividend receivables and transactions pending settlement.
Asset Class |  | Level 1 |  | Level 2 |  | Level 3 |  | Other |  | Total |  | Year End Allocation
|  | (in millions) |  |
Equities (a): |  |  |  |  |  |  |  |  |  |  |  |
Domestic |  | $ | 388.9 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 388.9 |  |  | 7.2 | %
International |  | 465.7 |  |  | — |  |  | — |  |  | — |  |  | 465.7 |  |  | 8.7 | %
Common Collective Trusts (b) |  | — |  |  | — |  |  | — |  |  | 463.9 |  |  | 463.9 |  |  | 8.7 | %
Subtotal – Equities |  | 854.6 |  |  | — |  |  | — |  |  | 463.9 |  |  | 1,318.5 |  |  | 24.6 | %
Fixed Income (a): |  |  |  |  |  |  |  |  |  |  |  |
United States Government and Agency Securities |  | 0.1 |  |  | 1,557.6 |  |  | — |  |  | — |  |  | 1,557.7 |  |  | 29.1 | %
Corporate Debt |  | — |  |  | 1,295.9 |  |  | — |  |  | — |  |  | 1,295.9 |  |  | 24.2 | %
Foreign Debt |  | — |  |  | 259.4 |  |  | — |  |  | — |  |  | 259.4 |  |  | 4.8 | %
State and Local Government |  | — |  |  | 57.1 |  |  | — |  |  | — |  |  | 57.1 |  |  | 1.1 | %
Other – Asset Backed |  | — |  |  | 1.3 |  |  | — |  |  | — |  |  | 1.3 |  |  | — | %
Subtotal – Fixed Income |  | 0.1 |  |  | 3,171.3 |  |  | — |  |  | — |  |  | 3,171.4 |  |  | 59.2 | %
Infrastructure (b) |  | — |  |  | — |  |  | — |  |  | 92.1 |  |  | 92.1 |  |  | 1.7 | %
Real Estate (b) |  | — |  |  | — |  |  | — |  |  | 232.6 |  |  | 232.6 |  |  | 4.4 | %
Alternative Investments (b) |  | — |  |  | — |  |  | — |  |  | 448.8 |  |  | 448.8 |  |  | 8.4 | %
Cash and Cash Equivalents (b) |  | — |  |  | 64.3 |  |  | — |  |  | 53.4 |  |  | 117.7 |  |  | 2.2 | %
Other – Pending Transactions and Accrued Income (c) |  | — |  |  | — |  |  | — |  |  | (28.2) |  |  | (28.2) |  |  | (0.5) | %
Total |  | $ | 854.7 |  |  | $ | 3,235.6 |  |  | $ | — |  |  | $ | 1,262.6 |  |  | $ | 5,352.9 |  |  | 100.0 | %
(a)Includes investment securities loaned to borrowers under the securities lending program. See the “Investments Held in Trust for Future Liabilities” section of Note 1 for additional information. (b)Amounts in “Other” column represent investments for which fair value is measured using net asset value per-share. (c)Amounts in “Other” column primarily represent accrued interest, dividend receivables and transactions pending settlement.
Other Postretirement Benefit Plans [Member] |
Assets within Fair Value Hierarchy |
Asset Class |  | Level 1 |  | Level 2 |  | Level 3 |  | Other |  | Total |  | Year End Allocation
|  | (in millions) |  |
Equities: |  |  |  |  |  |  |  |  |  |  |  |
Domestic |  | $ | 414.1 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 414.1 |  |  | 26.7 | %
International |  | 265.0 |  |  | — |  |  | — |  |  | — |  |  | 265.0 |  |  | 17.1 | %
Common Collective Trusts (a) |  | — |  |  | — |  |  | — |  |  | 169.1 |  |  | 169.1 |  |  | 10.9 | %
Subtotal – Equities |  | 679.1 |  |  | — |  |  | — |  |  | 169.1 |  |  | 848.2 |  |  | 54.7 | %
Fixed Income: |  |  |  |  |  |  |  |  |  |  |  |
Common Collective Trust – Debt (a) |  | — |  |  | — |  |  | — |  |  | 120.3 |  |  | 120.3 |  |  | 7.8 | %
United States Government and Agency Securities |  | 0.1 |  |  | 155.8 |  |  | — |  |  | — |  |  | 155.9 |  |  | 10.1 | %
Corporate Debt |  | — |  |  | 141.5 |  |  | — |  |  | — |  |  | 141.5 |  |  | 9.1 | %
Foreign Debt |  | — |  |  | 21.0 |  |  | — |  |  | — |  |  | 21.0 |  |  | 1.4 | %
State and Local Government |  | 62.9 |  |  | 7.8 |  |  | — |  |  | — |  |  | 70.7 |  |  | 4.6 | %
Subtotal – Fixed Income |  | 63.0 |  |  | 326.1 |  |  | — |  |  | 120.3 |  |  | 509.4 |  |  | 33.0 | %
Trust Owned Life Insurance: |  |  |  |  |  |  |  |  |  |  |  |
International Equities |  | — |  |  | 46.7 |  |  | — |  |  | — |  |  | 46.7 |  |  | 3.0 | %
United States Bonds |  | — |  |  | 110.3 |  |  | — |  |  | — |  |  | 110.3 |  |  | 7.1 | %
Subtotal – Trust Owned Life Insurance |  | — |  |  | 157.0 |  |  | — |  |  | — |  |  | 157.0 |  |  | 10.1 | %
Cash and Cash Equivalents (a) |  | 23.2 |  |  | — |  |  | — |  |  | 6.7 |  |  | 29.9 |  |  | 1.9 | %
Other – Pending Transactions and Accrued Income (b) |  | — |  |  | — |  |  | — |  |  | 4.8 |  |  | 4.8 |  |  | 0.3 | %
Total |  | $ | 765.3 |  |  | $ | 483.1 |  |  | $ | — |  |  | $ | 300.9 |  |  | $ | 1,549.3 |  |  | 100.0 | %
(a)Amounts in “Other” column represent investments for which fair value is measured using net asset value per-share. (b)Amounts in “Other” column primarily represent accrued interest, dividend receivables and transactions pending settlement.
Asset Class |  | Level 1 |  | Level 2 |  | Level 3 |  | Other |  | Total |  | Year End Allocation
|  | (in millions) |  |
Equities: |  |  |  |  |  |  |  |  |  |  |  |
Domestic |  | $ | 474.0 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 474.0 |  |  | 23.2 | %
International |  | 296.3 |  |  | — |  |  | — |  |  | — |  |  | 296.3 |  |  | 14.5 | %
Common Collective Trusts (a) |  | — |  |  | — |  |  | — |  |  | 265.0 |  |  | 265.0 |  |  | 13.0 | %
Subtotal – Equities |  | 770.3 |  |  | — |  |  | — |  |  | 265.0 |  |  | 1,035.3 |  |  | 50.7 | %
Fixed Income: |  |  |  |  |  |  |  |  |  |  |  |
Common Collective Trust – Debt (a) |  | — |  |  | — |  |  | — |  |  | 167.7 |  |  | 167.7 |  |  | 8.2 | %
United States Government and Agency Securities |  | — |  |  | 222.4 |  |  | — |  |  | — |  |  | 222.4 |  |  | 10.9 | %
Corporate Debt |  | — |  |  | 233.2 |  |  | — |  |  | — |  |  | 233.2 |  |  | 11.4 | %
Foreign Debt |  | — |  |  | 39.8 |  |  | — |  |  | — |  |  | 39.8 |  |  | 2.0 | %
State and Local Government |  | 91.9 |  |  | 13.6 |  |  | — |  |  | — |  |  | 105.5 |  |  | 5.1 | %
Subtotal – Fixed Income |  | 91.9 |  |  | 509.0 |  |  | — |  |  | 167.7 |  |  | 768.6 |  |  | 37.6 | %
Trust Owned Life Insurance: |  |  |  |  |  |  |  |  |  |  |  |
International Equities |  | — |  |  | 23.4 |  |  | — |  |  | — |  |  | 23.4 |  |  | 1.1 | %
United States Bonds |  | — |  |  | 171.3 |  |  | — |  |  | — |  |  | 171.3 |  |  | 8.4 | %
Subtotal – Trust Owned Life Insurance |  | — |  |  | 194.7 |  |  | — |  |  | — |  |  | 194.7 |  |  | 9.5 | %
Cash and Cash Equivalents (a) |  | 33.0 |  |  | — |  |  | — |  |  | 6.7 |  |  | 39.7 |  |  | 1.9 | %
Other – Pending Transactions and Accrued Income (b) |  | — |  |  | — |  |  | — |  |  | 6.0 |  |  | 6.0 |  |  | 0.3 | %
Total |  | $ | 895.2 |  |  | $ | 703.7 |  |  | $ | — |  |  | $ | 445.4 |  |  | $ | 2,044.3 |  |  | 100.0 | %
(a)Amounts in “Other” column represent investments for which fair value is measured using net asset value per-share. (b)Amounts in “Other” column primarily represent accrued interest, dividend receivables and transactions pending settlement.

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- Definition Tabular disclosure of the major categories of plan assets of pension plans and/or other employee benefit plans. This information may include, but is not limited to, the target allocation of plan assets, the fair value of each major category of plan assets, and the level within the fair value hierarchy in which the fair value measurements fall. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of the amounts that are recognized in the balance sheet (or statement of financial position) for pension plans and/or other employee benefit plans, showing separately the assets and current and noncurrent liabilities (if applicable) recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of the net gain (loss) and net prior service cost or credit recognized in other comprehensive income (loss) for the period for pension plans and/or other employee benefit plans, and reclassification adjustments of other comprehensive income (loss) for the period, as those amounts, including amortization of the net transition asset or obligation, are recognized as components of net periodic benefit cost. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (i) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of assumption used to determine benefit obligation and net periodic benefit cost of defined benefit plan. Includes, but is not limited to, discount rate, rate of compensation increase, expected long-term rate of return on plan assets and interest crediting rate. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of benefit obligation and plan assets for defined benefit pension plan with projected benefit obligation in excess of plan assets. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e2417-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921 + Details
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- Definition Tabular disclosure of the costs related to the various types of retirement plans including defined benefit pension plan cost, defined contribution plan cost, other postretirement benefit plan cost, and net periodic benefit cost. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of the changes in plan assets and benefit obligations recognized in other comprehensive income (loss) during the period. + References No definition available. + Details
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- Definition Tabular disclosure of benefits expected to be paid by pension plans and/or other employee benefit plans in each of the next five fiscal years and in the aggregate for the five fiscal years thereafter. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of the assumed health care cost trend rates for the next year used to measure the expected cost of benefits covered by the plans, including the ultimate trend rate(s) and when that rate is expected to be achieved. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (l) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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