Segment Information (Reconciliation of Consolidated Operating Income to Income Before Taxes) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Jan. 02, 2015	Dec. 27, 2013	Jan. 02, 2015	Dec. 27, 2013
Reconciliation of consolidated operating income to income before taxes [Abstract]
Operating income	$ 332us-gaap_OperatingIncomeLoss	$ 338us-gaap_OperatingIncomeLoss	$ 985us-gaap_OperatingIncomeLoss	$ 1,031us-gaap_OperatingIncomeLoss
Corporate G&A	(59)	(65)	(182)	(197)
Pension & OPEB actuarial & settlement (losses) gains	(462)csc_PensionExpenseFairValueAdjustment	114csc_PensionExpenseFairValueAdjustment	(463)csc_PensionExpenseFairValueAdjustment	114csc_PensionExpenseFairValueAdjustment
SEC settlement related charges	(195)us-gaap_LitigationSettlementAmount	0us-gaap_LitigationSettlementAmount	(195)us-gaap_LitigationSettlementAmount	0us-gaap_LitigationSettlementAmount
Interest expense	(37)us-gaap_InterestExpense	(38)us-gaap_InterestExpense	(112)us-gaap_InterestExpense	(112)us-gaap_InterestExpense
Interest income	4us-gaap_InterestIncomeOperating	4us-gaap_InterestIncomeOperating	14us-gaap_InterestIncomeOperating	11us-gaap_InterestIncomeOperating
Other income (expense), net	(1)us-gaap_OtherCostAndExpenseOperating	5us-gaap_OtherCostAndExpenseOperating	(6)us-gaap_OtherCostAndExpenseOperating	(16)us-gaap_OtherCostAndExpenseOperating
(Loss) income from continuing operations, before taxes	(418)	358	41	831
Change in accounting policy, increase on operating income	$ 208	$ 22	$ 251	$ 68

The aggregate total of expenses of the corporate office

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Pension Expense, Fair Value Adjustment

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- Definition

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(1)(i))

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

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-Subparagraph (SX 210.9-04.9)

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-Number 210

-Section 04

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Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities.

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Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

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Amount of the effect of a change in accounting principle on operating profit or loss.

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-Name Accounting Standards Codification

-Topic 250

-SubTopic 10

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The net result for the period of deducting operating expenses from operating revenues.

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No definition available.

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The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

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-Paragraph 2

-Subparagraph (SX 210.5-03.3)

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-Number 210

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