Operating loss carryforwards (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Operating Loss Carryforwards [Line Items]
Capital loss carryforward	$ 5,707	$ 4,582
Capital loss carryforward, expiration date	Mar. 31, 2020
Capital loss carryforward, valuation allowance	$ 5,700
Foreign Tax Authority and Federal and State Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	99,500
Operating Loss Carryforwards, Valuation Allowance	$ 53,200
Minimum | Foreign Tax Authority and Federal and State Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards, Expiration Date	Mar. 31, 2016
Maximum | Foreign Tax Authority and Federal and State Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards, Expiration Date	Mar. 31, 2035