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v3.21.1

Fair Value Measurements - Recurring Assets and Liabilities (Details) - USD ($) $ in Millions | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Liabilities |  |
Investment excludes receivables, payables and accrued income | $ 1 | $ 1
Recurring |  |
Assets |  |
Fair value, assets | 1,596 | 2,056
Liabilities |  |
Fair value, liabilities | (1) | 0
Net assets (liabilities) | 1,595 | 2,056
Recurring | FTRs | Derivative Liabilities |  |
Liabilities |  |
Fair value, liabilities | (1) | 0
Recurring | FTRs | Derivative Assets |  |
Assets |  |
Fair value, assets | 0 | 3
Recurring | Equity securities |  |
Assets |  |
Fair value, assets | 2 | 2
Recurring | U.S. state debt securities |  |
Assets |  |
Fair value, assets | 276 | 276
Recurring | Cash and cash equivalents |  |
Assets |  |
Fair value, assets | 1,281 | 1,734
Recurring | Other |  |
Assets |  |
Fair value, assets | 37 | 41
Recurring | Level 1 |  |
Assets |  |
Fair value, assets | 1,283 | 1,736
Liabilities |  |
Fair value, liabilities | 0 | 0
Net assets (liabilities) | 1,283 | 1,736
Recurring | Level 1 | FTRs | Derivative Liabilities |  |
Liabilities |  |
Fair value, liabilities | 0 | 0
Recurring | Level 1 | FTRs | Derivative Assets |  |
Assets |  |
Fair value, assets | 0 | 0
Recurring | Level 1 | Equity securities |  |
Assets |  |
Fair value, assets | 2 | 2
Recurring | Level 1 | U.S. state debt securities |  |
Assets |  |
Fair value, assets | 0 | 0
Recurring | Level 1 | Cash and cash equivalents |  |
Assets |  |
Fair value, assets | 1,281 | 1,734
Recurring | Level 1 | Other |  |
Assets |  |
Fair value, assets | 0 | 0
Recurring | Level 2 |  |
Assets |  |
Fair value, assets | 313 | 317
Liabilities |  |
Fair value, liabilities | 0 | 0
Net assets (liabilities) | 313 | 317
Recurring | Level 2 | FTRs | Derivative Liabilities |  |
Liabilities |  |
Fair value, liabilities | 0 | 0
Recurring | Level 2 | FTRs | Derivative Assets |  |
Assets |  |
Fair value, assets | 0 | 0
Recurring | Level 2 | Equity securities |  |
Assets |  |
Fair value, assets | 0 | 0
Recurring | Level 2 | U.S. state debt securities |  |
Assets |  |
Fair value, assets | 276 | 276
Recurring | Level 2 | Cash and cash equivalents |  |
Assets |  |
Fair value, assets | 0 | 0
Recurring | Level 2 | Other |  |
Assets |  |
Fair value, assets | 37 | 41
Recurring | Level 3 |  |
Assets |  |
Fair value, assets | 0 | 3
Liabilities |  |
Fair value, liabilities | (1) | 0
Net assets (liabilities) | (1) | 3
Recurring | Level 3 | FTRs | Derivative Liabilities |  |
Liabilities |  |
Fair value, liabilities | (1) | 0
Recurring | Level 3 | FTRs | Derivative Assets |  |
Assets |  |
Fair value, assets | 0 | 3
Recurring | Level 3 | Equity securities |  |
Assets |  |
Fair value, assets | 0 | 0
Recurring | Level 3 | U.S. state debt securities |  |
Assets |  |
Fair value, assets | 0 | 0
Recurring | Level 3 | Cash and cash equivalents |  |
Assets |  |
Fair value, assets | 0 | 0
Recurring | Level 3 | Other |  |
Assets |  |
Fair value, assets | $ 0 | $ 0

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