Related Party Transactions (Related Party Assets) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Mar. 31, 2021
Related party assets:
Amounts due to related parties	$ (730)	$ (1,353)
Related party assets	34,481	35,395
Blackwater [Member]
Related party assets:
Notes receivable	28,840	27,116
Mercury [Member]
Related party assets:
Notes receivable	$ 6,371	$ 9,632

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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+ Details