Cost Method Investment, Ownership Percentage

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License And Equipment Fee Receivable

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Minimum Number Of Rubidium Oscillators To Be Produced Per Year Under Agreement Terms

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This elements represents the minimum worth of the Rubidium Oscillators.

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Percentage of royalties payable on third party sales

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Royalty payable period

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The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

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Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

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Cash received from licensees for license fees during the current period.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Investment in Morion Inc - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	0 Months Ended	3 Months Ended		6 Months Ended
	Oct. 22, 2012	Oct. 31, 2012	Oct. 31, 2011	Oct. 31, 2012	Oct. 31, 2011
Related Party Transaction [Line Items]
Due from related party		$ 972,000		$ 972,000
Morion
Related Party Transaction [Line Items]
Cost method investment ownership percentage		4.60%		4.60%
Purchases from related party		6,000	60,000	18,000	145,000
Revenue from related party		66,000	241,000	96,000	1,000
Due to related party		6,000		6,000
Proceeds from license fees received				925,000
Minimum worth of rubidium oscillators				400,000
Minimum number of rubidium oscillators to be produced per year under agreement terms	5,000
License and equipment fee receivable	$ 2,700
Percentage of royalties payable on third party sales	5.00%
Royalty payable period	5 years