Stockholders' Equity Accelerated Share Repurchase (Details) (Accelerated Share Repurchase Agreement, Common Stock, USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended		3 Months Ended	0 Months Ended
	Apr. 03, 2015		Jan. 02, 2015	Nov. 08, 2015
Accelerated Share Repurchases [Line Items]
Notional ASR amount (in millions)	$ 427
Number of shares repurchased	4,155,193
Consideration	277
Average price per share (in USD per share)	$ 66.69
Second Quarter ASR Arrangement
Accelerated Share Repurchases [Line Items]
Notional ASR amount (in millions)	125	[1]
Number of shares repurchased	1,290,481	[1]	31,830
Consideration	75	[1]
Average price per share (in USD per share)	$ 58.12	[1]
Refund for cash prepayment on ASR			50
Fourth Quarter ASR Arrangement
Accelerated Share Repurchases [Line Items]
Notional ASR amount (in millions)	302	[2]
Number of shares repurchased	2,864,712	[2]
Consideration	202	[2]
Average price per share (in USD per share)	$ 70.55	[2]
Fourth Quarter ASR Arrangement | Maximum | Scenario, Forecast
Accelerated Share Repurchases [Line Items]
Refund for cash prepayment on ASR				$ 100

[1] In the third quarter of fiscal 2015, the Company received an additional 31,830 shares and a refund of the $50 million prepayment in cash upon settlement of the second quarter ASR arrangement.

[2] Consideration includes transaction costs. The final number of shares ultimately delivered and therefore the average price paid per share will be determined at maturity of the fourth quarter ASR arrangement. CSC may receive a refund of $100 million prepayment in cash or shares upon settlement of the fourth quarter ASR arrangement.