Concentration of Business, Significant Customers and Credit Risk (Details) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Sep. 30, 2017 USD ($) supplier tannery	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) supplier tannery	Sep. 30, 2016 USD ($)	Mar. 31, 2017 USD ($)
Concentration Risk [Line Items]
Number of tanneries | tannery	2		2
Number of suppliers | supplier	2		2
Property and equipment	$ 216,980		$ 216,980		$ 225,531
Long-lived Assets
Concentration Risk [Line Items]
Concentration risk (as a percent)			10.00%
International Net Sales
Concentration Risk [Line Items]
Concentration risk (as a percent)	37.30%	35.70%	38.80%	36.10%
Accounts Receivable | Unidentified Major Customer One
Concentration Risk [Line Items]
Concentration risk (as a percent)			11.90%		11.20%
Accounts Receivable | Unidentified Major Customer Two
Concentration Risk [Line Items]
Concentration risk (as a percent)			10.40%
UNITED STATES
Concentration Risk [Line Items]
Property and equipment	$ 198,287		$ 198,287		$ 206,077
Other Countries
Concentration Risk [Line Items]
Revenue	$ 160,200	$ 137,000	$ 209,400	$ 181,000
Concentration risk (as a percent)	33.20%	28.20%	30.30%	27.30%
Property and equipment	$ 18,693		$ 18,693		$ 19,454