Note 11 Employee Equity Incentive Plans (Narratives) (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
Jun. 30, 2014
Plan 2013 Approved on August 30, 2013 [Member]
Employee Equity Incentive Plans [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	2,000,000
Plan 2009 Approved on September 10, 2009 [Member]
Employee Equity Incentive Plans [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	900,000
Plan 2011 Approved on September 16, 2011 [Member]
Employee Equity Incentive Plans [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	600,000
Stock Options of Plans 2009 2011 and 2013 [Member]
Employee Equity Incentive Plans [Line Items]
Per Share Option Exercise Price as a Percentage of Fair Market Value on Grant Date Not Less Than	100.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years 0 months 0 days
Share-based Compensation Arrangement by Share-based Payment Award, Expiration from Award Date	10 years 0 months 0 days
Stock Appreciation Rights of Plans 2009 and 2011 [Member]
Employee Equity Incentive Plans [Line Items]
Per Share Option Exercise Price as a Percentage of Fair Market Value on Grant Date Not Less Than	100.00%
Share-based Compensation Arrangement by Share-based Payment Award, Expiration from Award Date	10 years 0 months 0 days
Amended and Restated 1999 Employee Stock Purchase Plan [Member]
Employee Equity Incentive Plans [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	1,550,000
ESPP Discounted Purchase Price Percentage	85.00%
ESPP Purchase Period	semi-annual
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	15.00%
Stock Issued During Period, Shares, Employee Stock Purchase Plans	50,417
Number of Employee Stock Purchase Plan Shares Available for Future Issuance	37,073
Equity Incentive Plans Total [Member]
Employee Equity Incentive Plans [Line Items]
Unrecognized Compensation Cost of Stock Option Granted	$ 5.1
Weighted Average Period of the Unrecognized Compensation Cost to be Recognized	2 years 6 months 0 days

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The discounted percentage of the fair market value of the Company's common stock in Employee Stock Purchase Plan.

+ References

No definition available.

+ Details

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- Definition

Purchase period of employee stock purchase plan.

+ References

No definition available.

+ Details

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- Definition

The stock option exercise price shall not be less than the percentage of fair market value specified on grant date.

+ References

No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, 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 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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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