Goodwill and intangible assets (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Dec. 31, 2015	Dec. 31, 2015	Mar. 31, 2015
Amortization of Intangible Assets	$ 300	$ 1,000
Finite-Lived Intangible Assets, Gross	9,324	9,324	$ 9,324
Finite-Lived Intangible Assets, Accumulated Amortization	5,485	5,485	4,507
Goodwill	10,657	10,657	10,657
Intangible Assets Gross Including Goodwill	$ 19,981	$ 19,981	$ 19,981
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		3 years 11 months 10 days
Minimum [Member]
Finite-Lived Intangible Asset, Useful Life		5 years
Maximum [Member]
Finite-Lived Intangible Asset, Useful Life		19 years