Discontinued Operations (Schedule Of Discontinued Operations) (Details) (USD $)	3 Months Ended				6 Months Ended				1 Months Ended	3 Months Ended
	Jun. 30, 2011		Jun. 30, 2010		Jun. 30, 2011		Jun. 30, 2010		Feb. 28, 2011 Pioneer Tunisia [Member]	Jun. 30, 2011 Pioneer Tunisia [Member]
Oil and gas			$ 40,096,000		$ 22,130,000		$ 75,848,000
Interest and other	18,000		42,619,000		4,586,000		44,414,000
Gain (loss) on disposition of assets, net	(4,574,000)				645,298,000
Total revenues and other income from discontinued operations	(4,556,000)		82,715,000		672,014,000		120,262,000
Oil and gas production			3,278,000		2,126,000		6,894,000
Depletion, depreciation and amortization			6,006,000	[1]			12,346,000	[1]
Exploration and abandonments	1,692,000		4,379,000		4,246,000		8,329,000
General and administrative	2,279,000		1,940,000		8,898,000		4,573,000
Accretion of discount on asset retirement obligations			103,000	[1]	81,000	[1]	204,000	[1]
Other	675,000		533,000		1,857,000		1,161,000
Total costs and expenses from discontinued operations	4,646,000		16,239,000		17,208,000		33,507,000
Income (loss) from discontinued operations before income taxes	(9,202,000)		66,476,000		654,806,000		86,755,000
Current tax provision	(1,963,000)	[2]	(5,737,000)	[2]	(9,537,000)	[2]	(5,294,000)	[2]
Deferred tax (provision) benefit	9,581,000	[1],[2]	(18,888,000)	[1],[2]	(232,211,000)	[1],[2]	(35,799,000)	[1],[2]
Income (loss) from discontinued operations	(1,584,000)		41,851,000		413,058,000		45,662,000
Percentage sale of ownership in subsidiary									100.00%
Cash proceeds from sale of subsidiaries, net									853,700,000
Gain on sale of subsidiaries, pretax									645,300,000
Reduction in net gain										4,600,000
Interest and other	18,454,000		16,952,000		51,141,000		34,960,000
Discontinued operations reinvestment reserve	5,200,000
Foreign tax carryover	3,700,000
Discontinued Operation, Current Foreign Tax Effect of Discontinued Operation	$ 3,753,000		$ 5,737,000		$ 5,602,000		$ 5,294,000

[1] Represents the significant noncash components of discontinued operations.

[2] During the three months ended June 30, 2011, the Company's taxes from discontinued operations include (i) a current provision and a deferred benefit amounting to $5.2 million associated with a Tunisian reinvestment reserve adjustment and (ii) a $3.7 million deferred foreign tax credit carryover benefit.