Stock-based Compensation (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Jun. 30, 2014 plan	Jun. 30, 2013
Stock options
Stock-based Compensation
Number of plans which reserved shares of common stock for issuance to executives and key employees	4
Expiration period	10 years
Major components of stock based compensation expense
Stock-based compensation expense	$ 228	$ 296
Exercised (in shares)	3,000	6,000
Stock options \| Cost of sales
Major components of stock based compensation expense
Stock-based compensation expense	108	138
Stock options \| Selling, general and administrative expenses
Major components of stock based compensation expense
Stock-based compensation expense	115	148
Stock options \| Research and development
Major components of stock based compensation expense
Stock-based compensation expense	5	10
Stock options \| Maximum
Stock-based Compensation
Vesting period	3 years
Stock options \| Minimum
Stock-based Compensation
Vesting period	1 year
Restricted stock
Major components of stock based compensation expense
Stock-based compensation expense	199	296
Restricted stock \| Cost of sales
Major components of stock based compensation expense
Stock-based compensation expense	21	63
Restricted stock \| Selling, general and administrative expenses
Major components of stock based compensation expense
Stock-based compensation expense	178	233
Chief executive officer \| Restricted stock
Stock-based Compensation
Period of restriction for sale of shares	90 days
Executive leadership \| Restricted stock
Stock-based Compensation
Period of restriction for sale of shares	90 days
Board of directors \| Restricted stock
Stock-based Compensation
Period of restriction for sale of shares	90 days
LTIP Plans
Stock-based Compensation
Performance period	2 years
Major components of stock based compensation expense
Stock-based compensation expense	567	377
LTIP Plans \| Cost of sales
Major components of stock based compensation expense
Stock-based compensation expense	217	114
LTIP Plans \| Selling, general and administrative expenses
Major components of stock based compensation expense
Stock-based compensation expense	289	214
LTIP Plans \| Research and development
Major components of stock based compensation expense
Stock-based compensation expense	$ 61	$ 49
2013/2014 LTIP \| Restricted stock units
Stock-based Compensation
Vesting period	3 years
2014/2015 LTIP \| Restricted stock units
Stock-based Compensation
Vesting period	3 years

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Represents the number of plans under which equity-based compensation is awarded by the entity.

+ References

No definition available.

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- Definition

The period of time over which performance targets need to be achieved to earn awards under equity-based compensation arrangements.

+ References

No definition available.

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- Definition

Represents the period of restriction for transfer of shares, awarded under the equity-based compensation arrangement.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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