Transactions with Affiliates (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Mar. 31, 2017
Transactions with Affiliates
Accounts receivable-affiliates	$ 1,552		$ 6,711
Accounts payable-affiliates	1,777		7,918
SemGroup
Transactions with Affiliates
Sales to related party	123	$ 71
Purchases from related party	1,017	2,025
Accounts receivable-affiliates	1,482		6,668
Accounts payable-affiliates	1,440		6,571
Equity method investees
Transactions with Affiliates
Sales to related party	98	405
Purchases from related party	27,906	30,647
Accounts receivable-affiliates	16		15
Accounts payable-affiliates	323		1,306
Equity method investees \| Loan Agreement
Transactions with Affiliates
Loan receivable from Victory Propane, LLC	$ 3,700
Loan agreement successive extension period	1 year
Entities affiliated with management
Transactions with Affiliates
Sales to related party	$ 83	77
Purchases from related party	197	$ 8,243
Accounts receivable-affiliates	54		28
Accounts payable-affiliates	14		$ 41
Minimum \| Entities affiliated with management
Transactions with Affiliates
Increase in property, plant and equipment	$ 100

Related Party Transaction, Loan Agreement Extension Period

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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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Amounts due from parties associated with the reporting entity as evidenced by a written promise to pay, due after 1 year (or 1 business cycle).

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Amount of acquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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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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