Income Taxes - Reconciliation of the beginning and ending balances of unrecognized tax benefits (Details) (USD $)	12 Months Ended
Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Income Tax Disclosure [Abstract]
Unrecognized tax benefits at beginning of period	$ 677,000	$ 670,000	$ 524,000
Additions based on tax positions related to the current year			146,000
Changes to tax positions of prior years		7,000
Settlements
Expirations
Unrecognized tax benefits at end of period	$ 677,000	$ 677,000	$ 670,000

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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

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The gross amount of increases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns.

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The gross amount of increases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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The gross amount of increases in unrecognized tax benefits resulting from settlements with taxing authorities.

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The gross amount of decreases in unrecognized tax benefits resulting from lapses of the applicable statutes of limitations.

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