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Business Segment Information (Schedule Of Operations By Reportable Segment) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Revenue	$ 1,080	$ 1,199	$ 1,381	$ 1,436	$ 1,417	$ 1,657	$ 1,659	$ 1,633	$ 5,096	$ 6,366	$ 7,214
Gross profit (loss)	94	87	74	70	(162)	30	28	39	325	(65)	417
Equity in earnings of unconsolidated affiliates	26	35	53	35	45	38	49	31	149	163	137
Impairment of goodwill					(446)				0	(446)	0
Asset Impairment and Restructuring Costs Charges									(70)	(214)	0
Operating income (loss)	$ 75	$ 75	$ 96	$ 64	$ (839)	$ 10	$ 25	$ 10	310	(794)	308
Capital expenditures									10	53	78
Depreciation									39	72	68
Non-strategic Business [Member]
Segment Reporting Information [Line Items]
Impairment of goodwill									0	(153)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue									4,441	5,575	6,217
Gross profit (loss)									298	162	422
Equity in earnings of unconsolidated affiliates									149	163	137
Impairment of goodwill									0	(293)	0
Asset Impairment and Restructuring Costs Charges									(66)	(180)	0
Operating income (loss)									254	(352)	312
Capital expenditures									10	53	78
Depreciation									39	66	61
Operating Segments [Member] \| Technology and Consulting [Member]
Segment Reporting Information [Line Items]
Revenue									324	353	330
Gross profit (loss)									77	53	69
Equity in earnings of unconsolidated affiliates									0	0	0
Impairment of goodwill									0	0	0
Asset Impairment and Restructuring Costs Charges									10	2	0
Operating income (loss)									62	49	70
Capital expenditures									0	0	0
Depreciation									2	2	2
Operating Segments [Member] \| Engineering and Construction [Member]
Segment Reporting Information [Line Items]
Revenue									3,454	4,584	4,956
Gross profit (loss)									224	141	263
Equity in earnings of unconsolidated affiliates									104	90	76
Impairment of goodwill									0	(293)	0
Asset Impairment and Restructuring Costs Charges									34	24	0
Operating income (loss)									295	(114)	278
Capital expenditures									6	19	10
Depreciation									17	23	23
Operating Segments [Member] \| Government Services [Member]
Segment Reporting Information [Line Items]
Revenue									663	638	931
Gross profit (loss)									(3)	(32)	90
Equity in earnings of unconsolidated affiliates									45	73	61
Impairment of goodwill									0	0	0
Asset Impairment and Restructuring Costs Charges									0	5	0
Operating income (loss)									37	25	145
Capital expenditures									0	0	1
Depreciation									6	8	9
Operating Segments [Member] \| Other Segments [Member]
Segment Reporting Information [Line Items]
Revenue									0	0	0
Gross profit (loss)									0	0	0
Equity in earnings of unconsolidated affiliates									0	0	0
Impairment of goodwill									0	0	0
Asset Impairment and Restructuring Costs Charges									22	149	0
Operating income (loss)									(140)	(312)	(181)
Capital expenditures									4	34	67
Depreciation									14	33	27
Operating Segments [Member] \| Non-strategic Business [Member]
Segment Reporting Information [Line Items]
Revenue									655	791	997
Gross profit (loss)									27	(227)	(5)
Equity in earnings of unconsolidated affiliates									0	0	0
Impairment of goodwill									0	(153)	0
Asset Impairment and Restructuring Costs Charges									4	34	0
Operating income (loss)									56	(442)	(4)
Capital expenditures									0	0	0
Depreciation									$ 0	$ 6	$ 7