Borrowings (Interest Rates and Company Borrowings) (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Interest and debt expense:
Weighted average interest rate during the quarter	1.39%	2.02%
Interest rate at quarter end	1.38%	1.67%
Maximum amount outstanding during the quarter	$ 1,088,000	$ 1,175,000
Average amount outstanding during the quarter	1,073,055	1,161,385
Facility fees	$ 71	$ 4

The average effective interest rate during the reporting period.

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Average amount borrowed under the credit facility during the period.

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Amount of the fees associated with providing collateral for the credit facility.

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The effective interest rate during the reporting period.

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