Employee Benefit Plans - Increase in Minimum Liability Included in Other Comprehensive Income (Loss) (Detail) (Postretirement Benefits, USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Postretirement Benefits
Pension Plans Postretirement And Other Employee Benefits [Line Items]
(Decrease) increase in minimum liability included in accumulated other comprehensive income	$ (38)	$ 16

After tax amount of additional minimum pension liability not yet recognized as a net periodic pension cost.

No definition available.

Name:	us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeMinimumPensionLiabilityAfterTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant