Concentration of Business, Significant Customers and Credit Risk (Details) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Mar. 31, 2016 USD ($)	Sep. 30, 2016 USD ($) supplier tannery	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) supplier tannery	Sep. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)
Concentration of Business, Significant Customers and Credit Risk [Line Items]
Property and equipment, net	$ 237,246	$ 246,723		$ 246,723
Number of tanneries | tannery		2		2
Number of suppliers | supplier		1		1
Cash equivalents	195,575	$ 65,312		$ 65,312
Cash	50,381	44,735		44,735
Total cash and cash equivalents	$ 245,956	$ 110,047	$ 99,775	$ 110,047	$ 99,775	$ 225,143
International net sales
Concentration of Business, Significant Customers and Credit Risk [Line Items]
Concentration risk (as a percent)		35.70%	38.10%	36.10%	37.80%
Net trade accounts receivable
Concentration of Business, Significant Customers and Credit Risk [Line Items]
Number of customers	one
Customer One | Net trade accounts receivable
Concentration of Business, Significant Customers and Credit Risk [Line Items]
Concentration risk (as a percent)	12.80%
US
Concentration of Business, Significant Customers and Credit Risk [Line Items]
Property and equipment, net	$ 211,111	$ 220,681		$ 220,681
All other countries
Concentration of Business, Significant Customers and Credit Risk [Line Items]
Property and equipment, net	$ 26,135	$ 26,042		$ 26,042
Concentration risk (as a percent)		28.20%	28.90%	27.30%	26.80%