The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock Options, Restricted Shares and Warrants (Summary of Exercise Price Range) (Details) - $ / shares	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding (shares)	2,017,046	2,426,836	2,716,317	3,312,523
Weighted Average Remaining Contractual Life (Years)	4 years 6 months 15 days
Weighted Average Exercise Price (usd per share)	$ 3.32	$ 3.50	$ 3.43	$ 3.42
Vested (shares)	1,811,146
Weighted Average Exercise Price (usd per share)	$ 3.43
$1.62 - 2.20
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit (usd per share)	1.62
Exercise Price Range, Upper Range Limit (usd per share)	$ 2.20
Outstanding (shares)	684,476
Weighted Average Remaining Contractual Life (Years)	4 years 11 months 5 days
Weighted Average Exercise Price (usd per share)	$ 1.98
Vested (shares)	558,776
Weighted Average Exercise Price (usd per share)	$ 1.98
$2.41 - 2.75
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit (usd per share)	2.41
Exercise Price Range, Upper Range Limit (usd per share)	$ 2.75
Outstanding (shares)	373,144
Weighted Average Remaining Contractual Life (Years)	6 years 2 months 27 days
Weighted Average Exercise Price (usd per share)	$ 2.45
Vested (shares)	360,744
Weighted Average Exercise Price (usd per share)	$ 2.44
$2.86 - 4.28
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit (usd per share)	2.86
Exercise Price Range, Upper Range Limit (usd per share)	$ 4.28
Outstanding (shares)	719,971
Weighted Average Remaining Contractual Life (Years)	4 years 26 days
Weighted Average Exercise Price (usd per share)	$ 3.41
Vested (shares)	652,171
Weighted Average Exercise Price (usd per share)	$ 3.44
$4.49 - 4.76
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit (usd per share)	4.49
Exercise Price Range, Upper Range Limit (usd per share)	$ 4.76
Outstanding (shares)	25,400
Weighted Average Remaining Contractual Life (Years)	2 years 4 months 24 days
Weighted Average Exercise Price (usd per share)	$ 4.64
Vested (shares)	25,400
Weighted Average Exercise Price (usd per share)	$ 4.64
$5.35 - 5.44
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit (usd per share)	5.35
Exercise Price Range, Upper Range Limit (usd per share)	$ 5.44
Outstanding (shares)	77,204
Weighted Average Remaining Contractual Life (Years)	3 years 11 days
Weighted Average Exercise Price (usd per share)	$ 5.39
Vested (shares)	77,204
Weighted Average Exercise Price (usd per share)	$ 5.39
$9.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit (usd per share)	$ 9.00
Outstanding (shares)	27,000
Weighted Average Remaining Contractual Life (Years)	1 year 10 months 13 days
Weighted Average Exercise Price (usd per share)	$ 9.00
Vested (shares)	27,000
Weighted Average Exercise Price (usd per share)	$ 9.00
$10.14 - 11.61
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit (usd per share)	10.14
Exercise Price Range, Upper Range Limit (usd per share)	$ 11.61
Outstanding (shares)	109,851
Weighted Average Remaining Contractual Life (Years)	1 year 7 months 28 days
Weighted Average Exercise Price (usd per share)	$ 10.87
Vested (shares)	109,851
Weighted Average Exercise Price (usd per share)	$ 10.87