Special Cash Dividend on Common Stock (Details) (USD $)	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Supplemental Cash Flow Elements [Abstract]
Dividends payable, amount per share	$ 1.00us-gaap_DividendsPayableAmountPerShare	$ 1.00us-gaap_DividendsPayableAmountPerShare	$ 5.00us-gaap_DividendsPayableAmountPerShare
Dividends payable, date declared	Feb. 04, 2015	Dec. 04, 2013	Nov. 07, 2012
Dividends payable, date of record	Mar. 06, 2015	Jan. 10, 2014	Nov. 19, 2012
Dividends payable, date to be paid	Mar. 17, 2015	Feb. 14, 2014	Nov. 30, 2012

Date the declared dividend will be paid, in CCYY-MM-DD format.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

+ Details

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Period Type:	duration

- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
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Period Type:	duration

- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Details

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