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v3.19.3.a.u2

Benefit Plans - Changes not yet recognized (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2019 USD ($)
Pension benefits |
Change in items not yet recognized as a component of defined benefit plans, net periodic cost |
Items not yet recognized as a component of net cost – December 31, 2018 | $ (198)
Prior service credit amortized to net cost | 56
Items not yet recognized as a component of net cost – December 31, 2019 | (142)
Postretirement benefits |
Change in items not yet recognized as a component of defined benefit plans, net periodic cost |
Items not yet recognized as a component of net cost – December 31, 2018 | (16)
Prior service credit amortized to net cost | 3
Items not yet recognized as a component of net cost – December 31, 2019 | $ (13)

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