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v3.22.1

Fair Value Measurements - Assets and Liabilities Measured on a Recurring Basis (Details) - USD ($) $ in Thousands | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Assets |  |
Commodity contracts, assets | $ 297,623 | $ 110,389
Commodity contracts, liabilities | (8,621) | (4,690)
Nuclear decommissioning trust | 1,227,465 | 1,294,757
Nuclear decommissioning trust, other | 568,428 | 567,266
Other special use funds | 349,042 | 358,410
Other special use funds, other | 1,112 | 936
Total assets | 1,874,130 | 1,763,556
Total assets, other | 560,919 | 563,512
Liabilities |  |
Gross derivative liability | (1,554) |
Gross derivative liability, other |  | 3,105
Amount reported on balance sheet | (1,706) | (4,373)
Equity securities |  |
Assets |  |
Nuclear decommissioning trust | 17,265 | 17,482
Nuclear decommissioning trust, other | 478 | (27,782)
Other special use funds | 28,180 | 48,506
Other special use funds, other | 1,112 | 936
U.S. commingled equity funds |  |
Assets |  |
Nuclear decommissioning trust | 567,950 | 595,048
U.S. Treasury debt |  |
Assets |  |
Nuclear decommissioning trust | 225,902 | 240,745
Other special use funds | 312,613 | 298,170
Corporate debt |  |
Assets |  |
Nuclear decommissioning trust | 196,300 | 203,454
Mortgage-backed securities |  |
Assets |  |
Nuclear decommissioning trust | 145,845 | 155,574
Municipal bonds |  |
Assets |  |
Nuclear decommissioning trust | 65,494 | 72,189
Other special use funds | 8,249 | 11,734
Other fixed income |  |
Assets |  |
Nuclear decommissioning trust | 8,709 | 10,265
Level 1 |  |
Assets |  |
Commodity contracts, assets | 0 | 0
Nuclear decommissioning trust | 242,689 | 286,009
Other special use funds | 339,681 | 345,740
Total assets | 582,370 | 631,749
Liabilities |  |
Gross derivative liability | 0 | 0
Level 1 | Equity securities |  |
Assets |  |
Nuclear decommissioning trust | 16,787 | 45,264
Other special use funds | 27,068 | 47,570
Level 1 | U.S. commingled equity funds |  |
Assets |  |
Nuclear decommissioning trust | 0 | 0
Level 1 | U.S. Treasury debt |  |
Assets |  |
Nuclear decommissioning trust | 225,902 | 240,745
Other special use funds | 312,613 | 298,170
Level 1 | Corporate debt |  |
Assets |  |
Nuclear decommissioning trust | 0 | 0
Level 1 | Mortgage-backed securities |  |
Assets |  |
Nuclear decommissioning trust | 0 | 0
Level 1 | Municipal bonds |  |
Assets |  |
Nuclear decommissioning trust | 0 | 0
Other special use funds |  | 0
Level 1 | Other fixed income |  |
Assets |  |
Nuclear decommissioning trust | 0 | 0
Level 2 |  |
Assets |  |
Commodity contracts, assets | 296,442 | 115,079
Nuclear decommissioning trust | 416,348 | 441,482
Other special use funds | 8,249 | 11,734
Total assets | 721,039 | 568,295
Liabilities |  |
Gross derivative liability | 0 | (4,740)
Level 2 | Equity securities |  |
Assets |  |
Nuclear decommissioning trust | 0 | 0
Other special use funds | 0 | 0
Level 2 | U.S. commingled equity funds |  |
Assets |  |
Nuclear decommissioning trust | 0 | 0
Level 2 | U.S. Treasury debt |  |
Assets |  |
Nuclear decommissioning trust | 0 | 0
Other special use funds | 0 | 0
Level 2 | Corporate debt |  |
Assets |  |
Nuclear decommissioning trust | 196,300 | 203,454
Level 2 | Mortgage-backed securities |  |
Assets |  |
Nuclear decommissioning trust | 145,845 | 155,574
Level 2 | Municipal bonds |  |
Assets |  |
Nuclear decommissioning trust | 65,494 | 72,189
Other special use funds | 8,249 | 11,734
Level 2 | Other fixed income |  |
Assets |  |
Nuclear decommissioning trust | 8,709 | 10,265
Level 3 |  |
Assets |  |
Commodity contracts, assets | 9,802 | 0
Nuclear decommissioning trust | 0 | 0
Other special use funds | 0 | 0
Total assets | 9,802 | 0
Liabilities |  |
Gross derivative liability | (152) | (2,738)
Level 3 | Equity securities |  |
Assets |  |
Nuclear decommissioning trust | 0 | 0
Other special use funds | 0 | 0
Level 3 | U.S. commingled equity funds |  |
Assets |  |
Nuclear decommissioning trust | 0 | 0
Level 3 | U.S. Treasury debt |  |
Assets |  |
Nuclear decommissioning trust | 0 | 0
Other special use funds | 0 | 0
Level 3 | Corporate debt |  |
Assets |  |
Nuclear decommissioning trust | 0 | 0
Level 3 | Mortgage-backed securities |  |
Assets |  |
Nuclear decommissioning trust | 0 | 0
Level 3 | Municipal bonds |  |
Assets |  |
Nuclear decommissioning trust | 0 | 0
Other special use funds | 0 | 0
Level 3 | Other fixed income |  |
Assets |  |
Nuclear decommissioning trust | 0 | 0
Fair Value Measured at Net Asset Value Per Share | U.S. commingled equity funds |  |
Assets |  |
Nuclear decommissioning trust | $ 567,950 | $ 595,048

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