Transactions with Affiliates and Other Related Parties (Details) (USD $)	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Related Party Transactions:
Production costs	$ 19,057,000	$ 15,797,000	$ 51,091,000	$ 41,106,000
Exploration expense	2,030,000	1,773,000	5,156,000	6,019,000
General and administrative expense	16,080,000	13,710,000	46,978,000	42,796,000
PDCM
Related Party Transactions:
Sales from natural gas marketing	4,774,000	2,894,000	12,742,000	7,459,000
Cost of natural gas marketing	4,680,000	2,838,000	12,492,000	7,313,000
Well operating and administrative services billed to PDCM	3,600,000	3,000,000	10,400,000	9,200,000
Affiliated Partnerships
Related Party Transactions:
Sales from natural gas marketing	348,000	145,000	931,000	368,000
Cost of natural gas marketing	341,000	142,000	913,000	360,000
PDCE proportionate share
Related Party Transactions:
Production costs	1,068,000	1,022,000	3,121,000	3,080,000
Exploration expense	127,000	110,000	366,000	357,000
General and administrative expense	$ 584,000	$ 370,000	$ 1,716,000	$ 1,168,000

- Definition

Exploration expenses (including prospecting) related to oil and gas producing entities and would be included in operating expenses of that entity. Costs incurred in identifying areas that may warrant examination and in examining specific areas that are considered to have prospects of containing oil and gas reserves, including costs of drilling exploratory wells and exploratory-type stratigraphic test wells. Exploration costs may be incurred both before acquiring the related property (sometimes referred to in part as prospecting costs) and after acquiring the property. Principal types of exploration costs, which include depreciation and applicable operating costs of support equipment and facilities and other costs of exploration activities, are: (i) Costs of topographical, geographical and geophysical studies, rights of access to properties to conduct those studies, and salaries and other expenses of geologists, geophysical crews, and others conducting those studies. Collectively, these are sometimes referred to as geological and geophysical or "G&G" costs. (ii) Costs of carrying and retaining undeveloped properties, such as delay rentals, ad valorem taxes on properties, legal costs for title defense, and the maintenance of land and lease records. (iii) Dry hole contributions and bottom hole contributions. (iv) Costs of drilling and equipping exploratory wells. (v) Costs of drilling exploratory-type stratigraphic test wells.

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