Long-Term Debt Foreign Seasonal Lines of Credit (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Debt Instrument [Line Items]
Line of credit facility, amount outstanding	$ 658,529
Unused lines of credit	$ 669,428
Foreign Line of Credit [Member]
Debt Instrument [Line Items]
Line of credit facility, amount outstanding		$ 330,254
Line of credit facility, current borrowing capacity		795,746
Unused lines of credit		10,899
Line of credit facility, amount issued but unfunded		$ 6,328
Minimum [Member] | Foreign Line of Credit [Member]
Debt Instrument [Line Items]
Line of credit facility, borrowing period	180 days
Maximum [Member] | Foreign Line of Credit [Member]
Debt Instrument [Line Items]
Line of credit facility, borrowing period	270 days