Sales and Other Operating Revenue - Receivables and Contract LIabilities (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Accounts Receivable, Net	$ 2,470	$ 2,470	$ 2,889
Revenue, Performance Obligation, Description of Timing		We typically receive payment within 30 days or less (depending on the terms of the invoice) once delivery is made.
Contract with Customer, Timing of Satisfaction of Performance Obligation and Payment		The agreements typically provide for negotiated payments to be made at stated milestones. The payments are not directly related to our performance under the contract and are recorded as deferred revenue to be recognized as revenue when the customer can utilize and benefit from their right to use the license. Payments are received in installments over the construction period.
Contract with Customer, Liability [Abstract]
Contract with Customer, Liability Beginning Balance		$ 206
Contract with Customer, Liability, Cash Received		(57)
Contract with Customer, Liability, Revenue Recognized		(133)
Contract with Customer, Liability Ending Balance	$ 130	130
Change in Contract with Customer, Liability [Abstract]
Contract with Customer, Liability, Revenue Recognized		133
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Explanation	We expect to recognize the contract liabilities as of June 30, 2019, as revenue between the remainder of 2019 and 2023.
Short-term Contract with Customer [Member]
Contract with Customer, Liability [Abstract]
Contract with Customer, Liability Ending Balance	$ 60	60
Long-term Contract with Customer [Member]
Contract with Customer, Liability [Abstract]
Contract with Customer, Liability Ending Balance	$ 70	$ 70

Payment received included in balance of obligation to transfer good or service to customer.

No definition available.

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For an unclassified balance sheet, the amount due from customers or clients for goods or services that have been delivered or sold in the normal course of business, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Description of effect, from relationship that timing of satisfaction of performance obligation has on timing of payment, on right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time and on obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Description of timing for satisfying performance obligation in contract with customer. Includes, but is not limited to, as services are rendered, and upon shipment, delivery or completion of service.

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Description of when remaining performance obligation is expected to be recognized as revenue.

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