Commitments and Contingencies (Details 2) (USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2014
Non-cancelable operating leases
Future minimum operating lease arrangements	$ 131.7
Natural Gas Sales Contracts [Member]
Delivery Commitments
Volume of gas deliverable (in Bcf)	34,700
Delivery term	12 months
Financial commitment upon nondelivery	146.4
Other Transportation And Delivery Commitments [Member]
Delivery Commitments
Delivery term	4 years
Financial commitment upon nondelivery	$ 2.0

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Total amount of product committed to be supplied under existing contracts or agreements.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Industry Guide

-Number 2

-Paragraph 8

-Subparagraph A

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Total financial obligation resulting from inability to meet short-term or long-term contractual delivery obligations.

No definition available.

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This element represents the period for delivery of oil and gas under terms of contracts and agreements.

No definition available.

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Amount of required minimum rental payments maturing over the next five years and beyond.

No definition available.

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