Income Taxes (Schedule Of Reconciliation Of Income Tax Provisions) (Details) (USD $)	12 Months Ended
Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Income Taxes [Abstract]
Tax expense at U.S. statutory rate	$ 5,667,281	$ 6,046,264	$ 5,700,630
State income taxes, net of Federal benefit	199,751	244,691	252,881
Domestic manufacturing deduction	(443,708)	(460,723)	(467,053)
Municipal interest	(28,456)	(118,282)	(235,470)
Other	(14,794)	15,669	(8,844)
Income Tax Expense (Benefit), Total	$ 5,380,074	$ 5,727,619	$ 5,242,144

Income Tax Reconciliation, Deductions, Domestic Manufacturing Deduction

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Income Tax Reconciliation, Municipal Interest

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Article 4

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a),(b)

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

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-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 13

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-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Subparagraph 2

-Article 4

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority noncontrolling interest income (loss), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, increase (decrease) in enacted tax rate, prior year income taxes, increase (decrease) in deferred tax asset valuation allowance, and other adjustments.

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