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Employee Benefit and Stock Compensation Plans Information regarding stock options (Details) - $ / shares		12 Months Ended
		Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Infromation regarding stock options [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	[1]	3,029	4,029	5,362	7,362
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price		$ 246.18	$ 258.16	$ 255.17	$ 235.00
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	[1]	3,002	3,975	5,229
$90.00 - $104.85 [Member]
Infromation regarding stock options [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number		134
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term		5 years 4 months 9 days
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price		$ 97.50
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number		107
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price		$ 97.50
$240.00 - $254.85 [Member]
Infromation regarding stock options [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number		1,899
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term		2 years 9 months 12 days
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price		$ 250.61
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number		1,899
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price		$ 16.71
$255.00 - $269.85 [Member]
Infromation regarding stock options [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number		996
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term		1 year 2 months 4 days
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price		$ 257.63
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number		996
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price		$ 257.63
$285.00 - $299.85 [Member]
Infromation regarding stock options [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price
[1] Options for all periods presented reflects a 1-for-15 reverse stock split which was effective on October 27, 2011

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[Line Items] for Infromation regarding stock options [Table]

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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.

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-Name Accounting Standards Codification



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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

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

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