Note 12 - Income Tax Charge / (Credit) - Components of Tax Credit (Details) (Parentheticals)	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Statement Line Items [Line Items]
Applicable tax rate	19.00%	20.00%	20.00%

The applicable income tax rate.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2017-01-01
-Paragraph 81
-Subparagraph c
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_c_ii&doctype=Standard
-URIDate 2017-03-09

Name:	ifrs-full_ApplicableTaxRate
Namespace Prefix:	ifrs-full_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration