Stock Plans 9 (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted	3.5	3.8	4.7
Weighted average grant date fair value	$ 26.21	$ 24.54	$ 21.41
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted	0.9	0.7	0.6
Weighted average grant date fair value	$ 23.72	$ 24.06	$ 21.30
1-Year PSUs for Fiscal Year 2012 Incentive Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period	1 year
1-Year PSUs for Fiscal Year 2012 Incentive Plans [Member] | Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted	1.2
Weighted average grant date fair value	$ 26.39
1-Year PSUs for Fiscal Year 2012 Incentive Plans [Member] | Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted	0.2
Weighted average grant date fair value	$ 25.40
1-Year PSUs for Fiscal Year 2011 Incentive Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period		1 year
1-Year PSUs for Fiscal Year 2011 Incentive Plans [Member] | Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted		1.1
Weighted average grant date fair value		$ 24.68
1-Year PSUs for Fiscal Year 2011 Incentive Plans [Member] | Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted		0.1
Weighted average grant date fair value		$ 24.48
1-Year PSUs for Fiscal Year 2010 Incentive Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period			1 year
1-Year PSUs for Fiscal Year 2010 Incentive Plans [Member] | Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted			2.2
Weighted average grant date fair value			$ 21.47
1-Year PSUs for Fiscal Year 2010 Incentive Plans [Member] | Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted			0	[1]
Weighted average grant date fair value			$ 21.38
3-Year PSUs for Fiscal Year 2010 Incentive Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period	3 years
Number of shares granted	0.2
Weighted average grant date fair value	$ 26.39
3-Year PSUs for Fiscal Year 2009 Incentive Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period		3 years
Number of shares granted		0.2
Weighted average grant date fair value		$ 24.68
3-Year PSUs for Fiscal Year 2008 Incentive Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period			3 years
Number of shares granted			0.3
Weighted average grant date fair value			$ 21.47
1-Year PSUs for Fiscal Year 2012 Sales Retention Equity Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period	1 year
1-Year PSUs for Fiscal Year 2012 Sales Retention Equity Program [Member] | Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted	0.2
Weighted average grant date fair value	$ 26.39
1-Year PSUs for Fiscal Year 2012 Sales Retention Equity Program [Member] | Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted	0.1
Weighted average grant date fair value	$ 23.41
1-Year PSUs for Fiscal Year 2011 Sales Retention Equity Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period		1 year
1-Year PSUs for Fiscal Year 2011 Sales Retention Equity Program [Member] | Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted		0.3
Weighted average grant date fair value		$ 24.68
1-Year PSUs for Fiscal Year 2011 Sales Retention Equity Program [Member] | Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted		0.1
Weighted average grant date fair value		$ 24.09
1-Year PSUs for Fiscal Year 2010 Sales Retention Equity Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period			1 year
1-Year PSUs for Fiscal Year 2010 Sales Retention Equity Program [Member] | Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted			0.4
Weighted average grant date fair value			$ 21.47
1-Year PSUs for Fiscal Year 2010 Sales Retention Equity Program [Member] | Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted			0.1
Weighted average grant date fair value			$ 21.36

[1] Shares granted amounted to less than 0.1 million.