v3.20.1

Statement of Changes in Combined Equity - USD ($) $ in Millions | Total | Parent Company net investment | Accumulated other comprehensive income (loss) | Noncontrolling interest
--- | --- | --- | --- | ---
Balance at beginning of period at Dec. 31, 2018 | $ 2,677 | $ 2,415 | $ 250 | $ 12
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |
Net income | 41 | 41 |  | 0
Other comprehensive income (loss) | 57 |  | 57 | 0
Change in ParentCo contribution | (27) | (27) |  |
Balance at end of period at Mar. 31, 2019 | 2,821 | 2,502 | 307 | 12
Balance at beginning of period at Dec. 31, 2019 | 2,728 | 2,419 | 295 | 14
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |
Net income | 60 | 60 |  | 0
Other comprehensive income (loss) | 25 |  | 25 | 0
Establishment of defined benefit plans (G) | 1,403 | (349) | 1,752 |
Change in ParentCo contribution | 217 | 217 |  |
Other | (1) |  |  | (1)
Balance at end of period at Mar. 31, 2020 | $ 1,626 | $ 3,045 | $ (1,432) | $ 13

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