Employee benefit plans - Estimated Future Benefit Payments (Details) $ in Millions	Dec. 31, 2019 USD ($)
Estimated Future Benefit Payments
2020	$ 32
2021	32
2022	32
2023	33
2024	33
Years 2025 - 2029	164
Pension
Estimated Future Benefit Payments
2020	31
2021	31
2022	31
2023	32
2024	32
Years 2025 - 2029	159
Other Postretirement
Estimated Future Benefit Payments
2020	1
2021	1
2022	1
2023	1
2024	1
Years 2025 - 2029	$ 5

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- Definition

Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

+ References

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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