Concentration Risk, Number of Large Customers

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- Definition

Sensitivity Analysis Of Fair Value, Fair Value Of Derivative Contracts, Impact Of Ten Percent Change In Commodity Prices

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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No definition available.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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The cash inflow from sales of all investments, including securities and other assets, having ready marketability and intended by management to be liquidated, if necessary, within the current operating cycle. Includes cash flows from securities classified as trading securities that were acquired for reasons other than sale in the short-term.

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Fair Value Measurements (Additional Information) (Details)	12 Months Ended
	Dec. 31, 2015 USD ($) customer	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Concentration Risk [Line Items]
Sale of short-term investments	$ 919,000,000	$ 473,000,000	$ 310,000,000
Impact of ten percent change in commodity prices	$ 100,000
Number of large customers \| customer	2
Plains Marketing \| Accounts receivable
Concentration Risk [Line Items]
Concentration of credit risk (less than 9 percent)	47.00%
Plains Marketing \| Total operating revenues
Concentration Risk [Line Items]
Concentration of credit risk (less than 9 percent)	33.00%
Shell Trading \| Accounts receivable
Concentration Risk [Line Items]
Concentration of credit risk (less than 9 percent)	21.00%
Remaining Customer Concentration Risk \| Accounts receivable
Concentration Risk [Line Items]
Concentration of credit risk (less than 9 percent)	9.00%
Reported Value Measurement
Concentration Risk [Line Items]
Fair value of long-term debt	$ 776,500,000	1,039,000,000
Estimate of Fair Value Measurement
Concentration Risk [Line Items]
Fair value of long-term debt	690,100,000	993,700,000
Swap [Member] \| Credit facility
Concentration Risk [Line Items]
Long-term debt	$ 66,667,000
Interest rate	1.0425%
Interest rate cash flow hedge liability at fair value	$ 200,000	$ 800,000