Supplemental Cash Flow Information (Detail) (USD $)	6 Months Ended
Sep. 30, 2013	Sep. 30, 2012
Income taxes paid	$ 551,000	$ 2,286,000
Interest paid	0	0
Accrued dividends	$ 543,956	$ 883,928

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 210

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

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-Paragraph 15

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

-Publisher SEC

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

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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