Business Segments, Concentration of Business, and Credit Risk and Significant Customers (Long-lived Assets) (Details) $ in Thousands		3 Months Ended
		Jun. 30, 2015 USD ($) customer tannery	Mar. 31, 2015 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)
Business segment information
Property and equipment, by major country		$ 239,381	$ 232,317
Number of Customers Considered Concentration Risk | customer		1
Number of Tanneries | tannery		2
Cash and cash equivalents
Money market fund accounts		$ 110,895	127,900
Cash		57,849	97,243
Total cash and cash equivalents		$ 168,744	$ 225,143	$ 158,226	$ 245,088
Long-lived Assets
Business segment information
Concentration risk (as a percent)		10.00%
International Net Sales
Business segment information
Concentration risk (as a percent)		37.10%		37.50%
Concentration risk benchmark (as a percent)		10.00%
Net Trade Accounts Receivable
Business segment information
Concentration risk benchmark (as a percent)		10.00%
Net Trade Accounts Receivable | Customer One
Business segment information
Concentration risk (as a percent)		13.20%	11.80%		10.60%
Net Trade Accounts Receivable | Customer Two
Business segment information
Concentration risk (as a percent)					11.00%
US
Business segment information
Property and equipment, by major country		$ 205,721	$ 196,513
All other countries
Business segment information
Property and equipment, by major country	[1]	$ 33,660	$ 35,804

[1] No other country’s long-lived assets comprised more than 10% of total long-lived assets as of June 30, 2015 and March 31, 2015.