Business Segments, Concentration of Business, and Credit Risk and Significant Customers (Details 3) (USD $) In Thousands, unless otherwise specified						3 Months Ended
	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013 tannery	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2014 International Net Sales	Mar. 31, 2014 International Net Sales	Jun. 30, 2014 Net Trade Accounts Receivable	Jun. 30, 2014 Net Trade Accounts Receivable Customer One	Mar. 31, 2014 Net Trade Accounts Receivable Customer One	Jun. 30, 2014 Net Trade Accounts Receivable Customer Two	Mar. 31, 2014 Net Trade Accounts Receivable Customer Two	Jun. 30, 2014 US	Mar. 31, 2014 US	Jun. 30, 2014 All other countries	Mar. 31, 2014 All other countries
Business segment information
Property and equipment, by major country	$ 187,804	$ 184,570											$ 150,337	$ 148,178	$ 37,467	$ 36,392	[1]
Concentration risk benchmark (as a percent)						10.00%		10.00%
Concentration risk (as a percent)						37.50%	35.30%		11.10%	11.80%	10.40%	11.40%
Number of Tanneries			2
Cash and cash equivalents
Money market fund accounts	63,221	143,816
Cash	95,005	101,272
Total cash and cash equivalents	$ 158,226	$ 245,088		$ 49,126	$ 64,591

[1] No other country’s long-lived assets comprised more than 10% of total long-lived assets as of June 30, 2014 and March 31, 2014.