Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Mar. 31, 2019	Apr. 01, 2018
Supplemental Cash Flow Information [Abstract]
Cumulative-effect adjustment from adoption of accounting guidance	$ 997	$ 0	$ 997		$ 997
Shares issued for contingent compensation payment	425	425	425
Non-cash financing activities:
Dividends declared but not paid	5,325	8,026	5,325	$ 5,673
Member distributions declared but not paid	$ 8,206	10,505	8,206	$ 17,081
Establishment of net deferred tax assets related to offerings		$ 37,394	$ 37,924

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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