Borrowings (Interest Rates and Company Borrowings) (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Interest and debt expense:
Weighted average interest rate during the quarter	1.65%	1.76%
Interest rate at quarter end	1.65%	1.77%
Maximum amount outstanding during the quarter	$ 191,000	$ 164,632
Average amount outstanding during the period	180,714	142,170
Facility fees	$ 94	$ 117