Employee Benefit Plans - Amounts Recognized in the Consolidated Balance Sheets (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Postretirement Benefits
Pension Plans Postretirement And Other Employee Benefits [Line Items]
Total Liabilities	$ 618	$ 674	$ 948
Pension Plan
Pension Plans Postretirement And Other Employee Benefits [Line Items]
Total Liabilities	3,032	3,479	3,266
Current Liabilities | Postretirement Benefits
Pension Plans Postretirement And Other Employee Benefits [Line Items]
Total Liabilities	60	82
Noncurrent Liabilities | Postretirement Benefits
Pension Plans Postretirement And Other Employee Benefits [Line Items]
Total Liabilities	558	592
Noncurrent Liabilities | Pension Plan
Pension Plans Postretirement And Other Employee Benefits [Line Items]
Total Liabilities	$ 3,032	$ 3,479