Annual report pursuant to Section 13 and 15(d)

Income taxes - Reconciliation of Effective Tax Rate (Details)

v3.6.0.2
Income taxes - Reconciliation of Effective Tax Rate (Details) - Her Majesty's Revenue and Customs (HMRC)
6 Months Ended 12 Months Ended
Dec. 31, 2015
Dec. 31, 2016
Jun. 30, 2015
Jun. 30, 2014
Income taxes        
UK tax rate 20.00% 20.00% 20.75% 22.50%
Permanent differences relating to foreign exchange (8.70%)   3.40%  
Surrender of R&D expenditures for R&D tax credit (4.50%) (5.90%) (5.50%) (12.10%)
Change in valuation allowances (10.80%) (14.70%) (20.70%) (16.20%)
Other 4.20% (0.70%) 0.90% 5.00%
Effective income tax rate 0.20% (1.30%) (1.10%) (0.80%)