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v3.21.2

Fair Value Measurements - Assets and Liabilities Measured on a Recurring Basis (Details) - USD ($) $ in Thousands | Jun. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Assets |  |
Commodity contracts, assets | $ 109,614 | $ 4,749
Commodity contracts, liabilities | (1,368) | (4,271)
Nuclear decommissioning trust | 1,223,088 | 1,138,435
Nuclear decommissioning trust, other | 693,330 | 592,227
Other special use funds | 358,436 | 254,509
Other special use funds, other | 952 | 504
Total assets | 1,691,138 | 1,397,693
Total assets, other | 692,914 | 588,460
Liabilities |  |
Gross derivative liability, other | 83 | 2,986
Amount reported on balance sheet | (1,512) | (18,619)
Equity securities |  |
Assets |  |
Nuclear decommissioning trust | 13,243 | 11,968
Nuclear decommissioning trust, other | (9,506) | (17,828)
Other special use funds | 20,856 | 37,841
Other special use funds, other | 952 | 504
U.S. commingled equity funds |  |
Assets |  |
Nuclear decommissioning trust | 702,836 | 610,055
U.S. Treasury debt |  |
Assets |  |
Nuclear decommissioning trust | 167,584 | 164,514
Other special use funds | 324,418 | 203,220
Corporate debt |  |
Assets |  |
Nuclear decommissioning trust | 150,681 | 149,509
Mortgage-backed securities |  |
Assets |  |
Nuclear decommissioning trust | 119,481 | 99,623
Municipal bonds |  |
Assets |  |
Nuclear decommissioning trust | 59,876 | 89,705
Other special use funds | 13,162 | 13,448
Other fixed income |  |
Assets |  |
Nuclear decommissioning trust | 9,387 | 13,061
Level 1 |  |
Assets |  |
Commodity contracts, assets | 0 | 0
Nuclear decommissioning trust | 190,333 | 194,310
Other special use funds | 344,322 | 240,557
Total assets | 534,655 | 434,867
Liabilities |  |
Gross derivative liability | 0 | 0
Level 1 | Equity securities |  |
Assets |  |
Nuclear decommissioning trust | 22,749 | 29,796
Other special use funds | 19,904 | 37,337
Level 1 | U.S. commingled equity funds |  |
Assets |  |
Nuclear decommissioning trust | 0 | 0
Level 1 | U.S. Treasury debt |  |
Assets |  |
Nuclear decommissioning trust | 167,584 | 164,514
Other special use funds | 324,418 | 203,220
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 | 0
Level 1 | Other fixed income |  |
Assets |  |
Nuclear decommissioning trust | 0 | 0
Level 2 |  |
Assets |  |
Commodity contracts, assets | 84,594 | 9,016
Nuclear decommissioning trust | 339,425 | 351,898
Other special use funds | 13,162 | 13,448
Total assets | 437,181 | 374,362
Liabilities |  |
Gross derivative liability | (1,586) | (20,498)
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 | 150,681 | 149,509
Level 2 | Mortgage-backed securities |  |
Assets |  |
Nuclear decommissioning trust | 119,481 | 99,623
Level 2 | Municipal bonds |  |
Assets |  |
Nuclear decommissioning trust | 59,876 | 89,705
Other special use funds | 13,162 | 13,448
Level 2 | Other fixed income |  |
Assets |  |
Nuclear decommissioning trust | 9,387 | 13,061
Level 3 |  |
Assets |  |
Commodity contracts, assets | 26,388 | 4
Nuclear decommissioning trust | 0 | 0
Other special use funds | 0 | 0
Total assets | 26,388 | 4
Liabilities |  |
Gross derivative liability | (9) | (1,107)
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 | $ 702,836 | $ 610,055

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