Regulatory Matters (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2011
Kinder Morgan Interstate Gas Transmission Pipeline - Franklin to Hastings Expansion Project [Abstract]
Dekatherms of capacity requested in filing	10,000
Estimated total cost to complete the Franklin to Hastings expansion project	$ 18.4
FERC Natural Gas Fuel Tracker Proceedings - Trailblazer Pipeline Company
EFAP rate implemented by Trailblazer	8.14
EFAP rate later approved by FERC	8.69
Expense recognized as a result of FERC approved EFAP	13.1
FERC Natural Gas Fuel Tracker Proceedings - Rockies Express Pipeline
Expense recorded resulting from adjustment to its fuel tracker receivable	$ 8.2

Firm transportation capacity requested in filing for Franklin to Hastings Expansion Project. This is measured in dekatherms per day.

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The Expansion Fuel Adjustment Percentage rate implimented to comply with prior order.

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The Expansion Fuel Adjustment Percentage later approved by the FERC.

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Estimated total cost to complete the Franklin to Hastings Expansion Project.

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The expense recognized as a result of implementing the FERC approved EFAP.

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The expense recorded resulting from an adjustment to its fuel tracker receivable.

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Disclosures related to FERC Natural Gas Fuel Tracker Proceedings involving Rockies Express Pipeline.

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Disclosures related to FERC Natural Gas Fuel Tracker Proceedings involving Trailblazer Pipeline Company.

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Project to expand Kinder Morgan Interstate Gas Transmission Pipeline.

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