Borrowings (Interest Rates and Company Borrowings) (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Interest and debt expense:
Weighted average interest rate during the quarter	2.02%	3.73%
Interest rate at quarter end	1.67%	3.69%
Maximum amount outstanding during the quarter	$ 1,175,000	$ 990,000
Average amount outstanding during the quarter	1,161,385	967,358
Facility fees	$ 4	$ 62

The average effective interest rate during the reporting period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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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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-SubTopic 10
-Section S99
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Maximum amount borrowed under the credit facility at any time during the period.

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