Shareholders' Equity - Summary of dividends declared (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Mar. 31, 2015
Declaration Date May 2, 2014
Stockholders Equity Note [Line Items]
Declaration Date	May 02, 2014
Per Share Dividend	$ 0.170
Record Date	May 14, 2014
Total Amount (In thousands)	$ 3,432
Payment Date	May 23, 2014
Declaration Date July 21, 2014
Stockholders Equity Note [Line Items]
Declaration Date	Jul. 21, 2014
Per Share Dividend	$ 0.170
Record Date	Aug. 04, 2014
Total Amount (In thousands)	3,446
Payment Date	Aug. 15, 2014
Declaration Date October 20, 2014
Stockholders Equity Note [Line Items]
Declaration Date	Oct. 20, 2014
Per Share Dividend	$ 0.170
Record Date	Nov. 03, 2014
Total Amount (In thousands)	3,445
Payment Date	Nov. 14, 2014
Declaration Date January 20, 2015
Stockholders Equity Note [Line Items]
Declaration Date	Jan. 20, 2015
Per Share Dividend	$ 0.170
Record Date	Feb. 03, 2015
Total Amount (In thousands)	$ 3,445
Payment Date	Feb. 13, 2015

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

+ References

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

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

+ References

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.15(5))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 15

-Subparagraph a

-Article 7

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 15

-Subparagraph 5

-Article 9

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.15(5))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

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

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