Contract Assets and Contract Liabilities Components of Net Contract Assets (Liabilities) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Revenue from Contract with Customer [Abstract]
Contract assets	$ 1,590	$ 1,349	$ 0
Contract liabilities — current	(669)	(565)	0
Contract liabilities — non-current	(31)	(28)	$ 0
Contract with Customer, Asset, Net	890	$ 756
Increase (Decrease) in Contract with Customer, Assets	241
Increase in contract liabilities	107
Contract with Customer, Liability, Revenue Recognized	$ 457

Increase (Decrease) in Contract with Customer, Assets

No definition available.

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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

+ References

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- Definition

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

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

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- Definition

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.

+ References

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Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

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- References

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