Share-based compensation (Share-based Compensation Expense) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014
Share-based compensation
Share-based compensation expense	$ 3,086	$ 3,282	$ 10,427	$ 11,515
Cost of revenue
Share-based compensation
Share-based compensation expense	266	317	771	932
Research and development
Share-based compensation
Share-based compensation expense	511	797	1,598	2,473
Selling and marketing
Share-based compensation
Share-based compensation expense	829	599	2,978	2,228
General and administrative
Share-based compensation
Share-based compensation expense	$ 1,480	$ 1,569	$ 5,080	$ 5,882

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration