Separation and Other Termination Costs	12 Months Ended
Dec. 31, 2020
Restructuring and Related Activities [Abstract]
Separation and Other Termination Costs	Separation and Other Termination Costs Workforce Reductions In 2020, 2019 and 2018, we incurred charges of approximately $44 million, $12 million and $38 million related to one-time termination benefits for certain employees. Subsequent to December 31, 2020, we reduced our workforce by 220 employees or approximately 15%, primarily in Oklahoma City and incurred charges of approximately $20 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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