Long-Term Debt and Credit Facilities Long-Term Debt and Credit Facilities (Parentheticals) (Details)	Mar. 31, 2014
3.00% senior unsecured notes, due January 15, 2015
Debt Instrument, Interest Rate, Stated Percentage	3.00%
4.375% senior unsecured notes, due January 15, 2020
Debt Instrument, Interest Rate, Stated Percentage	4.375%
2.00% senior unsecured notes, due September 30, 2016
Debt Instrument, Interest Rate, Stated Percentage	2.00%
1.30% senior unsecured notes, due April 1, 2018
Debt Instrument, Interest Rate, Stated Percentage	1.30%
4.10% senior unsecured notes, due April 1, 2043
Debt Instrument, Interest Rate, Stated Percentage	4.10%