Employee Benefit Plans (Components of net periodic benefit costs post retirement benefits) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Postemployment Benefits [Abstract]
Service cost for benefits earned during the period	$ 256	$ 240	$ 769	$ 720
Interest cost on accumulated postretirement benefit	204	188	611	564
Other components	22	9	66	27
Net periodic postretirement benefit cost	$ 482	$ 437	$ 1,446	$ 1,311