Stock-Based Compensation Plans (Details 1)	3 Months Ended	9 Months Ended
Dec. 31, 2011	Jan. 01, 2011	Dec. 31, 2011	Jan. 01, 2011
Restricted Stock Units [Member]
Weighted average assumptions in estimation of fair value of stock options
Risk-free interest rate	0.40%	0.80%	0.70%	1.00%
Dividend yield	2.40%	2.30%	2.10%	2.50%
Employee Stock Option [Member]
Weighted average assumptions in estimation of fair value of stock options
Expected life of options (years)	5.2	5.2	5.2	5.1
Expected stock price volatility	35.00%	32.00%	32.00%	35.00%
Risk-free interest rate	0.90%	1.40%	1.40%	1.80%
Dividend yield	2.40%	2.30%	2.30%	2.50%
Employee Stock [Member]
Weighted average assumptions in estimation of fair value of stock options
Expected life of options (years)			1.25	1.25
Expected stock price volatility			29.00%	33.00%
Risk-free interest rate			0.20%	0.30%
Dividend yield			2.40%	2.30%

The period of time an equity-based award is expected to be outstanding. An equity-based award's expected term is generally determined based on, among other factors, the instrument's contractual term and the effects of employees' expected exercise and post-vesting employment termination behavior.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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