Business Segment Information (Schedule Of Operations By Reportable Segment) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Segment Reporting Information [Line Items]
Revenues:	$ 1,073	$ 1,199	$ 3,078	$ 4,016
Gross profit (loss):	(36)	87	106	231
Equity in earnings of unconsolidated affiliates	19	35	81	123
Asset impairment and restructuring charges:	(7)	(15)	(21)	(34)
Segment operating income (loss):	(67)	75	61	235
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues:	1,063	1,083	2,924	3,478
Gross profit (loss):	50	73	208	215
Equity in earnings of unconsolidated affiliates	19	35	81	123
Asset impairment and restructuring charges:	(7)	(14)	(21)	(31)
Segment operating income (loss):	18	64	159	196
Operating Segments [Member] \| Technology and Consulting [Member]
Segment Reporting Information [Line Items]
Revenues:	67	79	262	231
Gross profit (loss):	17	17	49	57
Equity in earnings of unconsolidated affiliates	0	0	0	0
Asset impairment and restructuring charges:	(1)	0	(1)	(1)
Segment operating income (loss):	16	16	44	53
Operating Segments [Member] \| Engineering and Construction [Member]
Segment Reporting Information [Line Items]
Revenues:	595	828	1,822	2,758
Gross profit (loss):	1	48	65	155
Equity in earnings of unconsolidated affiliates	11	26	52	87
Asset impairment and restructuring charges:	(6)	(13)	(20)	(25)
Segment operating income (loss):	(2)	61	76	201
Operating Segments [Member] \| Government Services [Member]
Segment Reporting Information [Line Items]
Revenues:	401	176	840	489
Gross profit (loss):	32	8	94	3
Equity in earnings of unconsolidated affiliates	8	9	29	36
Asset impairment and restructuring charges:	0	0	0	0
Segment operating income (loss):	25	15	104	34
Operating Segments [Member] \| Other Segments [Member]
Segment Reporting Information [Line Items]
Revenues:	0	0	0	0
Gross profit (loss):	0	0	0	0
Equity in earnings of unconsolidated affiliates	0	0	0	0
Asset impairment and restructuring charges:	0	(1)	0	(5)
Segment operating income (loss):	(21)	(28)	(65)	(92)
Operating Segments [Member] \| Non-strategic Business [Member]
Segment Reporting Information [Line Items]
Revenues:	10	116	154	538
Gross profit (loss):	(86)	14	(102)	16
Equity in earnings of unconsolidated affiliates	0	0	0	0
Asset impairment and restructuring charges:	0	(1)	0	(3)
Segment operating income (loss):	$ (85)	$ 11	$ (98)	$ 39

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(12))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66022249&loc=d3e33749-111570

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-Section S99
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