Acquisitions and Divestitures (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended			9 Months Ended			9 Months Ended			3 Months Ended	9 Months Ended					6 Months Ended		9 Months Ended		6 Months Ended
	Dec. 30, 2011	Sep. 30, 2011	Dec. 31, 2010	Dec. 30, 2011	Dec. 31, 2010	Dec. 30, 2011 NPS [Member]	Dec. 30, 2011 AppLabs Acquisition [Member]	Dec. 30, 2011 AppLabs Acquisition [Member] Customer Relationships [Member]	Dec. 30, 2011 AppLabs Acquisition [Member] Software [Member]	Dec. 30, 2011 iSOFT Group Limited [Member]	Dec. 30, 2011 iSOFT Group Limited [Member]	Dec. 31, 2010 iSOFT Group Limited [Member]	Dec. 30, 2011 iSOFT Group Limited [Member] Customer Relationships [Member]	Dec. 30, 2011 iSOFT Group Limited [Member] Software [Member]	Dec. 30, 2011 iSOFT Group Limited [Member] Trade Names [Member]	Sep. 30, 2011 Other Acquisition [Member]	Oct. 01, 2010 Other Acquisition [Member]	Dec. 30, 2011 Other Acquisition [Member]	Dec. 31, 2010 Other Acquisition [Member]	Oct. 01, 2010 Other Acquisition [Member] NPS [Member]	Dec. 30, 2011 Other Acquisition [Member] NPS [Member]	Dec. 31, 2010 Other Acquisition [Member] NPS [Member]	Dec. 30, 2011 Other Acquisition [Member] BSS [Member]	Dec. 31, 2010 Other Acquisition [Member] BSS [Member]
Summary of consolidated information as reported [Abstract]
Revenues	$ 3,764		$ 3,995	$ 11,763	$ 11,840		$ 34				$ 81
Net loss	(1,390)		242	(4,084)	569		(1)
Basic EPS (in dollars per share)	$ (8.96)		$ 1.57	$ (26.35)	$ 3.69
Diluted EPS (in dollars per share)	$ (8.96)		$ 1.54	$ (26.35)	$ 3.64
Total cash consideration paid							171			200	200							28	61
Goodwill impairment	60	2,685	0	2,745	0						37	290
Acquisition costs										2	11	11
Estimated fair value							33	31	2	212	212		92	116	4			7	16
Estimated use lives (in years)															1
Estimated useful life, lower range (in years)								2	1				10	5				4
Estimated useful life, upper range (in years)								8	5				13	7				10
Results of acquisitions included in consolidated financial statements [Abstract]
Revenues	3,764		3,995	11,763	11,840		34				81
Operating loss											(58)
Currency gains											15
Pre-tax net income (loss)	(1,438)		230	(4,191)	686						(43)
Assets acquired and liabilities assumed [Abstract]
Cash and cash equivalents							4			32	32
Trade and other receivables							20			117	117
Current assets																		8
Other current assets							8			11	11
Deferred tax assets										22	22
Intangible assets							33	31	2	212	212		92	116	4			7	16
Software																			8
Property and equipment							4			20	20							2	1
Trade payables and accrued expenses							(27)			(60)	(60)
Deferred revenue										(54)	(54)
Current income tax liabilities										(6)	(6)
Current liabilities																		6
Other liabilities							(2)
Debt										(315)	(315)
Deferred tax, uncertain tax positions, and other long-term liabilities							(18)			(67)	(67)
Total identifiable net assets acquired							22			(88)	(88)
Goodwill							149			288	288							17	36		14	26	3	10
Total purchase price							171			200	200							28	61
Fair value of accounts receivable [Abstract]
Uncollectible contractual receivables										10	10
Acquired debt paid off											298
Tax deductible goodwill						14				71	71
Goodwill allocation adjustment											20
Intangible assets allocation adjustment											10
Additional consideration of contingent on achievement of agreed revenue targets for future periods																		2
Number of acquisitions (in number of entity)																2	2
Divestiture [Abstract]
Total consideration from divestiture of businesses																				56
Net current assets derecognized																				18
Net property and equipment derecognized																				1
Goodwill derecognized																				10
Transaction costs from divestiture of business																				1
Pre-tax gain from divestiture of business																				26
Transaction costs included (excluded) due to integration of acquisition into Company's operations										(11)	(11)	11
Unaudited pro forma summary of consolidated information [Abstract]
Revenue	3,764		4,048	11,841	11,984
Net (loss) income attributable to CSC common shareholders	$ (1,390)		$ 221	$ (4,153)	$ 475
Basic EPS (in dollars per share)	$ (8.96)		$ 1.43	$ (26.79)	$ 3.08
Diluted EPS (in dollars per share)	$ (8.96)		$ 1.41	$ (26.79)	$ 3.04