Other Investments (Schedule of Unrealized Gains and Losses Related to Equity Securities) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Other Investments [Abstract]
Net gains and losses recognized during the period on equity securities	$ 74,084		$ 71,649
Less: Net gains and losses recognized during the period on equity securities sold during the period
Unrealized gains and losses recognized during the reporting period on equity securities still held at the reporting date	$ 74,084		$ 71,649