Consolidated Statements Of Stockholders' Equity (USD $) In Thousands, except Share data, unless otherwise specified	Pioneer Southwest [Member] Additional Paid-In Capital [Member]	Pioneer Southwest [Member] Noncontrolling Interests [Member]	Pioneer Southwest [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interests [Member]	Total
Beginning Balance at Dec. 31, 2008				$ 1,246	$ 2,909,735	$ (411,659)	$ 988,786	$ 88,788	$ 102,717	$ 3,679,613
Beginning Balance, shares at Dec. 31, 2008				114,546,000
Sale of Pioneer Southwest common units, net of tax
Issuance of Pioneer Southwest common units, net of tax	33,388
Dividends declared ($0.08 per share)							(9,388)			(9,388)
Exercise of long-term incentive plan stock options and employee stock purchases						18,110	(9,604)			8,506
Exercise of long-term incentive plan stock options and employee stock purchases, shares				468,000
Purchase of treasury stock						(21,662)			(259)	(21,921)
Purchase of treasury stock, shares				(1,276,000)
Tax benefits related to stock-based compensation					1					1
Compensation costs:
Vested compensation awards, net				6	(6)
Vested compensation awards, net, shares				637,000
Compensation costs included in net income (loss)					38,332				232	38,564
Issuance of Common Stock					33,388			(5,844)	33,439	60,983
Cash contributions from noncontrolling interests									150	150
Cash distributions to noncontrolling interests									(20,012)	(20,012)
Net income (loss)							(52,106)		9,839	(42,267)
Deferred hedging activity, net of tax:
Hedge fair value changes, net								10,477	3,692	14,169
Net hedge gains included in continuing operations								(42,412)	(22,955)	(65,367)
Ending Balance at Dec. 31, 2009				1,252	2,981,450	(415,211)	917,688	51,009	106,843	3,643,031
Ending Balance, shares at Dec. 31, 2009				114,375,000
Sale of Pioneer Southwest common units, net of tax
Issuance of Pioneer Southwest common units, net of tax
Dividends declared ($0.08 per share)							(9,455)			(9,455)
Exercise of long-term incentive plan stock options and employee stock purchases				1	2,577	7,811	(3,014)			7,375
Exercise of long-term incentive plan stock options and employee stock purchases, shares				266,000
Purchase of treasury stock						(13,835)			(204)	(14,039)
Purchase of treasury stock, shares				(278,000)
Tax benefits related to stock-based compensation					(153)					(153)
Compensation costs:
Vested compensation awards, net				9	(8)					1
Vested compensation awards, net, shares				946,000
Compensation costs included in net income (loss)					38,902				1,283	40,185
Cash contributions from noncontrolling interests									1,151	1,151
Cash distributions to noncontrolling interests									(26,837)	(26,837)
Net income (loss)							605,208		40,787	645,995
Deferred hedging activity, net of tax:
Net hedge gains included in continuing operations								(43,648)	(17,581)	(61,229)
Ending Balance at Dec. 31, 2010				1,262	3,022,768	(421,235)	1,510,427	7,361	105,442	4,226,025
Ending Balance, shares at Dec. 31, 2010				115,309,000
Common stock, issued				5,500,000
Sale of Pioneer Southwest common units, net of tax	26,915	8,176	35,091
Issuance of Pioneer Southwest common units, net of tax	8,104	40,688	48,792		8,104
Dividends declared ($0.08 per share)							(9,498)			(9,498)
Exercise of long-term incentive plan stock options and employee stock purchases					951	3,097	(352)			3,696
Exercise of long-term incentive plan stock options and employee stock purchases, shares				76,000
Purchase of treasury stock						(40,157)			(198)	(40,355)
Purchase of treasury stock, shares				(439,000)
Conversion of 2.875% senior convertible notes					(20)	14				(6)
Tax benefits related to stock-based compensation					31,087					31,087
Disposition of subsidiary					(510)					(510)
Compensation costs:
Vested compensation awards, net				14	(14)
Vested compensation awards, net, shares				1,410,000
Compensation costs included in net income (loss)					40,422				1,251	41,673
Issuance of Common Stock				55	484,105					484,160
Cash contributions from noncontrolling interests									(26,702)	(26,702)
Net income (loss)							834,489		47,425	881,914
Deferred hedging activity, net of tax:
Net hedge gains included in continuing operations								(10,491)	(13,738)	(24,229)
Ending Balance at Dec. 31, 2011				$ 1,331	$ 3,613,808	$ (458,281)	$ 2,335,066	$ (3,130)	$ 162,344	$ 5,651,138
Ending Balance, shares at Dec. 31, 2011				121,856,000