CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	9 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities:
Net income	$ 9,522us-gaap_NetIncomeLoss	$ 2,826us-gaap_NetIncomeLoss
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Write-off of engineering project development qualification units	81	571
Shipped qualification assets	142bzc_ShippedQualificationAssets	747bzc_ShippedQualificationAssets
Depreciation and amortization	1,537	1,129
Non-cash reserve accretion	221bzc_NonCashReserveAccretion	256bzc_NonCashReserveAccretion
Stock based compensation	849us-gaap_ShareBasedCompensation	517us-gaap_ShareBasedCompensation
Provision for losses on accounts receivable	13us-gaap_ProvisionForDoubtfulAccounts	13us-gaap_ProvisionForDoubtfulAccounts
Deferred taxes-net	(4,311)	90
Changes in assets and liabilities:
(Increase) decrease in accounts receivable and other receivables	8,897	251
(Increase) decrease in inventories	(5,542)us-gaap_IncreaseDecreaseInInventories	(6,134)us-gaap_IncreaseDecreaseInInventories
(Increase) decrease in income taxes receivable	(435)
(Increase) decrease in other assets	407	(178)
Increase (decrease) in accounts payable	(2,088)	784
Increase (decrease) in accrued compensation	(917)	(1,356)
Increase (decrease) in accrued income taxes	1,900	662
Increase (decrease) in other liabilities	(884)	(2,010)
Net cash provided by (used in) operating activities	9,392	(1,832)
Cash flows from investing activities:
Capital expenditures	(295)	(742)
Capitalized qualification units and pre-qualification assets	(44)	(1,349)
Net cash used in investing activities	(339)	(2,091)
Cash flows from financing activities:
Payment of debt issue costs		(33)us-gaap_PaymentsOfDebtIssuanceCosts
Exercise of stock options	662	677
Net cash provided by financing activities	662	644
Increase (decrease) in cash	9,715	(3,279)
Cash at beginning of period	6,021	6,688
Cash at end of period	15,736	3,409
Supplemental information:
Interest payments	19us-gaap_InterestPaid	33us-gaap_InterestPaid
Income tax payments	$ 258us-gaap_IncomeTaxesPaid	$ 980us-gaap_IncomeTaxesPaid

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