Related Party Transactions (Details) (USD $)
In Millions, unless otherwise specified

Sep. 30, 2014

Dec. 31, 2013

Summary of balance sheet affiliate balances [Abstract]

Natural gas imbalance receivable

$ 1

$ 3

Accounts payable

Natural gas imbalance payable

^[1]

Note receivable

^[2]

Financing obligations

$ 175

^[3]

$ 169

^[3]

[1]	Included in “Other current liabilities” on our Consolidated Balance Sheets.
[2]	We participate in EPB’s cash management program which matches the short-term cash surpluses and needs of participating affiliates, thus minimizing total borrowings from outside sources. EPB uses the cash management program to settle intercompany transactions between participating affiliates. The interest rate on this note is variable and was 1.9% as of September 30, 2014 and December 31, 2013. These amounts are included in “Note receivable from affiliate” on our Consolidated Balance Sheets.
[3]	Represents financing obligations payable to WYCO Development L.L.C. related to Totem Gas Storage Facility and High Plains Pipeline, of which $6 million and $5 million, respectively, is included in “Current portion of debt” on our Consolidated Balance Sheets as of September 30, 2014 and December 31, 2013.

- Definition

Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Amounts due within 1 year (or 1 business cycle) from other related parties which are not otherwise stated in the taxonomy.

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- Definition

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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- Definition

For an unclassified balance sheet, amounts due from parties associated with the reporting entity as evidenced by a written promise to pay.

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COLORADO INTERSTATE GAS COMPANY, L.L.C. 10-Q