Note 4 Fair Value (Narratives) (Details) (USD $)	3 Months Ended	9 Months Ended
Dec. 31, 2014	Dec. 31, 2014	Mar. 31, 2014
Auction Market Preferred Securities [Abstract]
Collateralized Asset Value Exceeding Value of ARPS Percentage	300.00%	300.00%
Auction Rate Preferred Securities, Credit Ratings	at least AA
Auction Rate Preferred Securities, Percentage Collateralized	100.00%
Debt Instrument [Line Items]
Debt, Fair Value	$ 50,000,000	$ 50,000,000	$ 51,600,000
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Impairment of Marketable Securities	$ 945,000	$ 945,000

Description of the credit rating of auction rate preferred securities given by a credit rating agency.

No definition available.

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- Definition

The percentage rate that the auction rate preferred securities are collaterized.

+ References

No definition available.

+ Details

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- Definition

Collateralized asset value exceeding the value of ARPS in percentage.

+ References

No definition available.

+ Details

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- Details

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

+ Details

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- Definition

The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 8B

-URI http://asc.fasb.org/extlink&oid=27724398&loc=SL6284393-111563

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