Represents the amount of member interests, as a percent, that are allowed to be purchased under an agreement.

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Represents the amount of member interests, as a percent, which may be required to be purchased by right of a member in an agreement.

+ References

No definition available.

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- Definition

Represents the cash outflow for payments to 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.

+ References

No definition available.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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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).

+ References

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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Amount of interest capitalized during the period.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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No definition available.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

No definition available.

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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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The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value.

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Note 9 - Related-Party Transactions (Details Textual) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended			9 Months Ended		12 Months Ended
	Oct. 21, 2019	Apr. 30, 2019	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Due from Related Parties, Current, Total			$ 1,873	$ 1,043		$ 1,873		$ 1,043
Contract with Customer, Liability, Total			5,700	5,900		5,700		5,900
Payments to Acquire Property, Plant, and Equipment, Total						9,428	$ 29,560
Tangible Asset Impairment Charges, Total						2,316	442
Equity Method Investments			0			0
Cimarron Express [Member]
Other than Temporary Impairment Losses, Investments, Total						2,000		10,000
Interest Costs Capitalized			$ 400			$ 1,700
DEVCO [Member]
Member Interests, Percent, Right to Purchase			100.00%			100.00%
Ergon [Member] \| Cimarron Express [Member]
Other than Temporary Impairment Losses, Investments, Total								10,000
Ergon [Member] \| Cimarron Express [Member]
Noncontrolling Interest, Ownership Percentage by Parent			50.00%			50.00%
Ergon [Member] \| DEVCO [Member]
Member Interests, Percent, Right to Require Purchase			100.00%			100.00%
Equity Method Investments			$ 10,400			$ 10,400
Cimarron Express [Member]
Payments to Acquire Property, Plant, and Equipment, Total								30,600
Tangible Asset Impairment Charges, Total				20,900
Gain (Loss) on Disposition of Assets, Total		$ 1,400
Ergon [Member]
Revenue from Related Parties			9,300		$ 11,100	27,200	38,600
Due from Related Parties, Current, Total			1,800	1,000		1,800		1,000
Contract with Customer, Liability, Total			4,200	$ 6,500		4,200		$ 6,500
Ergon [Member] \| Crude Oil Purchases [Member]
Related Party Transaction, Purchases from Related Party			32,800		$ 44,400	98,600	$ 74,900
Due to Related Parties, Current, Total			$ 11,400			$ 11,400
Ergon [Member] \| Crude Oil Purchases [Member] \| Subsequent Event [Member]
Payments to Related Parties	$ 11,400