Income Taxes (Details) (USD $)	3 Months Ended				9 Months Ended
	Dec. 30, 2011	Sep. 30, 2011	Jul. 01, 2011	Dec. 31, 2010	Dec. 30, 2011	Dec. 31, 2010
Income Taxes [Abstract]
Effective tax rate	3.10%			(6.10%)	2.80%	17.90%
Recognized benefits related to research and development (R&D) credits				$ 68,000,000
Favorable impact on the effective tax rate due to recognized benefits related to R&D (in hundredths)				29.60%		9.90%
Valuation allowance against prior year deferred tax assets of U.K. operating entities	65,000,000
Unfavorable impact on the effective tax rate due to valuation allowance (in hundredths)	4.50%				1.60%
Income tax benefits due to change in tax status of subsidiary			121,000,000
Favorable impact on the effective tax rate due to change in tax status of a foreign subsidiary (in hundredths)					2.90%
Tax benefits recognized due to audit settlements and expiration of statute of limitations		112,000,000
Favorable impact on effective tax rate due to settlement of tax audits and expiration of statute of limitations (in hundredths)					2.70%
Impairment of goodwill	60,000,000	2,685,000,000		0	2,745,000,000	0
Statutory tax rate (in hundredths)	35.00%				35.00%
NHS contract charge	1,500,000,000
Decrease in uncertain tax positions, net of tax attributes and excluding interest and penalties					187,000,000
Tax attributes on uncertain tax positions					75,000,000
Decrease in uncertain tax positions due to settlement of IRS examination and lapse of statute of limitations, net of tax attributes and excluding interest and penalties		186,000,000
Tax attributes on uncertain tax positions related to settlement of IRS examination and lapse of statute of limitations		26,000,000
Increase in uncertain tax positions related to acquisitions of two companies, net of tax attributes		13,000,000
Tax attributes on uncertain tax positions related to company acquisitions		49,000,000
Liability for uncertain tax positions including interest and penalties	217,000,000				217,000,000
Liability for interest recognized, net of tax	30,000,000				30,000,000
Tax related to interest liability on uncertain tax positions	18,000,000				18,000,000
Liability for penalties recognized	15,000,000				15,000,000
Interest benefit due to settlement with IRS					36,000,000
Interest benefit due to settlement with IRS, net of tax					23,000,000
Penalties released due to settlement with IRS					19,000,000
Uncertain tax positions that would impact effective tax rate	118,000,000				118,000,000
Range of possible reduction in liability for uncertain tax positions - maximum					$ 20,000,000