Basis of Presentation Income Before Income Tax (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Jan. 02, 2015	Dec. 27, 2013	Jan. 02, 2015	Dec. 27, 2013	Mar. 28, 2014
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest [Abstract]
Gross favorable	$ 17	$ 26	$ 89	$ 101
Gross unfavorable	(3)	(12)	(20)	(38)
Total net adjustments, before taxes and non-controlling interest	14	14	69	63
Impact on diluted EPS from continuing operations (usd per share)	$ 0.06	$ 0.06	$ 0.27	$ 0.26
Unbilled recoverable amounts primarily from governments that are expected to be collected after one year	51		51		46
Depreciation expense	$ 145us-gaap_Depreciation	$ 165us-gaap_Depreciation	$ 469us-gaap_Depreciation	$ 498us-gaap_Depreciation

Change in Estimate, Effect of Change on Diluted Earnings Per Share

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- Definition

Gross Change In Pretax Earnings Due To Change In Estimate, Favorable

+ References

No definition available.

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- Definition

Gross Change In Pretax Earnings Due To Change In Estimate, Unfavorable

+ References

No definition available.

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- Definition

Net increase (decrease) in pre-tax earnings due to changes in estimated profitability on contracts. Revisions to estimates at completion are reflected in results of operations as a change in accounting estimate in the period in which the facts that give rise to the revision become known to management.

+ References

No definition available.

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- Definition

Amounts included in unbilled accounts receivable, primarily from US and other governments, that are expected to be collected after one year.

+ References

No definition available.

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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