Segment Information Segment Other Significant Items Reconciliation (Table) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting, Other Significant Reconciling Item [Line Items]
Capital Expenditures	[1]	$ 361	$ 285	$ 188
Depreciation and amortization	[2]	205	186	180
Ingalls [Member]
Segment Reporting, Other Significant Reconciling Item [Line Items]
Capital Expenditures	[1]	131	97	53
Depreciation and amortization	[2]	73	68	65
Newport News Shipbuilding [Member]
Segment Reporting, Other Significant Reconciling Item [Line Items]
Capital Expenditures	[1]	224	176	130
Depreciation and amortization	[2]	107	109	102
Technical Solutions [Member]
Segment Reporting, Other Significant Reconciling Item [Line Items]
Capital Expenditures	[1]	6	8	5
Depreciation and amortization	[2]	$ 25	9	$ 13
Corporate Segment [Member]
Segment Reporting, Other Significant Reconciling Item [Line Items]
Capital Expenditures	[1]		$ 4

[1] Net of grant proceeds for capital expenditures

[2] Excluding amortization of debt issuance costs