Acquisitions and Dispositions (Pro Forma Information) (Details) - SGT and Aspire Defence - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Revenue	$ 5,060	$ 5,057
Net income attributable to KBR	$ 367	$ 342
Diluted earnings per share (usd per share)	$ 2.59	$ 2.41

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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-Publisher FASB
-Name Accounting Standards Codification
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