Derivatives (Narratives) (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Total notional amount of Company's variable interest rate swaps	$ 117,600
Notional amount of operating lease	6,200
Change in fair value of cash flow hedges, net of tax	3,082	$ 6,149	$ 6,027
Loss reclassified from AOCI into income (effective portion)	3,893	$ 8,628	$ 12,616
Reclassify net losses on interest rate contracts from AOCI to earnings over the next twelve months	$ 700