Exit and Disposal Costs	12 Months Ended
Dec. 31, 2019
Restructuring And Related Activities [Abstract]
Exit and Disposal Costs	12. Exit and Disposal Costs In 2018, we incurred severance expense of $38 million (2017: $18 million) associated with asset sales and cost savings initiatives in response to low crude oil prices. In 2019, we paid accrued severance costs of $4 million (2018: $40 million; 2017: $48 million).

The entire disclosure for restructuring and related activities. Description of restructuring activities such as exit and disposal activities, include facts and circumstances leading to the plan, the expected plan completion date, the major types of costs associated with the plan activities, total expected costs, the accrual balance at the end of the period, and the periods over which the remaining accrual will be settled.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-URI http://asc.fasb.org/topic&trid=2175745

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