Commitments and Contingencies (General Commitments) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Minimum Investor Partners Return On Investment			10.00%
Maximum Investor Partners Return On Investment			12.00%
Net partnership revenues subordinated	$ 0.4	$ 2.1	$ 3.8	$ 4.3
Long-term Purchase Commitment, Amount			36.4
EP Energy Acquisition
Contractual Obligation, Due in Next Twelve Months	4.4		4.4
Contractual Obligation, Due in Second Year	8.6		8.6
Contractual Obligation, Due in Third Year	2.1		2.1
Contractual Obligation, Due in Fourth Year	0		0
Contractual Obligation, Due in Fifth Year	$ 0		$ 0
Minimum
Partnership obligations to purchase units from investor partners			5.00%
Maximum
Partnership obligations to purchase units from investor partners			10.00%

Maximum investor partners return on Investment.

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- Definition

Minimum percent return on investment per year an investor partner will receive on their investment in the Drilling Partnerships over a specified period, typically the first five to seven years, in accordance with the terms of the agreements.

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No definition available.

+ Details

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- Definition

Net partnership revenues subordinated.

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No definition available.

+ Details

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- Definition

The Partnership is not obligated to purchase more than a percentage of the units of Drilling Partnerships in any calendar year.

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No definition available.

+ Details

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- Definition

Amount of contractual obligation maturing in the fifth fiscal year following the latest fiscal year.

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No definition available.

+ Details

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- Definition

Amount of contractual obligation maturing in the fourth fiscal year following the latest fiscal year.

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No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount of contractual obligation maturing in the next fiscal year following the latest fiscal year.

+ References

No definition available.

+ Details

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- Definition

Amount of contractual obligation maturing in the second fiscal year following the latest fiscal year.

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No definition available.

+ Details

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- Definition

Amount of contractual obligation maturing in the third fiscal year following the latest fiscal year.

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No definition available.

+ Details

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- Definition

The minimum amount the entity agreed to spend under the long-term purchase commitment.

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No definition available.

+ Details

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