Acquisition and Dispositions of Properties Narrative (Details) (San Juan, Subsequent Event, USD $) In Millions, unless otherwise specified	1 Months Ended
Oct. 31, 2014 acre
San Juan \| Subsequent Event
Gas and Oil Acreage [Line Items]
Acres of unproved leasehold, Net	15,000
Payment for unproved leasehold	$ 22.8

Fractional interest owned based on working interests or other economic arrangements of lease area on which wells have not been drilled or completed to a point that would permit the production of commercial quantities of oil and gas regardless of whether or not such area contains proved reserves.

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

-Publisher SEC

-Name Industry Guide

-Number 2

-Paragraph 5

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