Transactions with Affiliates - Related Party Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Transactions with Affiliates
Accounts receivable-affiliates	$ 8,591	$ 9,435
Accounts payable-affiliates	73	119
Entities affiliated with management
Transactions with Affiliates
Sales to related party	0	18,402	$ 8,367
Purchases from related party	1,489	1,239	3,799
Accounts receivable-affiliates	1	728
Accounts payable-affiliates	46	12
NGL Energy Holdings LLC
Transactions with Affiliates
Accounts receivable-affiliates	8,483	8,245
Equity method investees
Transactions with Affiliates
Sales to related party	0	0	203
Purchases from related party	1,091	3,249	2,120
Accounts receivable-affiliates	107	462
Accounts payable-affiliates	$ 27	107
WPX Energy
Transactions with Affiliates
Sales to related party		39,129	48,222
Purchases from related party		$ 216,487	313,578
SemGroup
Transactions with Affiliates
Sales to related party			$ 458

The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

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Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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