Other Current Liabilities - Other Current Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Mar. 31, 2014
Other Liabilities Disclosure [Abstract]
Engineering project reserves	$ 1,572bzc_EngineeringProjectReservesCurrent	$ 1,530bzc_EngineeringProjectReservesCurrent
Environmental reserves	2,085	1,673
Accrued medical benefits cost	798us-gaap_AccruedEmployeeBenefitsCurrent	621us-gaap_AccruedEmployeeBenefitsCurrent
Accrued commissions	529us-gaap_AccruedSalesCommissionCurrent	618us-gaap_AccruedSalesCommissionCurrent
Other	885us-gaap_OtherAccruedLiabilitiesCurrent	772us-gaap_OtherAccruedLiabilitiesCurrent
Total	$ 5,869us-gaap_OtherLiabilitiesCurrent	$ 5,214us-gaap_OtherLiabilitiesCurrent

Carrying value as of the balance sheet date of obligations, excluding pension and other postretirement benefits, incurred through that date and payable for perquisites provided to employees pertaining to services received from them. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for sales commissions. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Aggregate carrying amount of current liabilities (due within one year or within the normal operating cycle if longer) not separately disclosed in the balance sheet. Includes costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered and of liabilities not separately disclosed.

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