Benefit Plans - Pension benefit payments (Details) - Pension Plan - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
US
Benefit plans
Cash contributions made in period	$ 2
Expected contribution in next fiscal year	1
Expected future benefit payments
2019	19
2020	20
2021	22
2022	22
2023	24
Years 2024 - 2028	123
Non-US
Benefit plans
Cash contributions made in period	4	$ 5
Expected contribution in next fiscal year	3
Expected future benefit payments
2019	11
2020	11
2021	11
2022	12
2023	13
Years 2024 - 2028	$ 66

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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