Other Expense (Schedule Of Components Of Other Expense) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011		Jun. 30, 2012		Jun. 30, 2011
Other Expense [Abstract]
Transportation commitment charges	$ 9,227	[1]	$ 5,688	[1]	$ 17,680	[1]	$ 10,960	[1]
Above market drilling rig rates	5,760	[2]	5,410	[2]	10,746	[2]	10,569	[2]
Terminated drilling rig contract charges	8,960	[3]	0	[3]	8,960	[3]	0	[3]
Inventory valuation charges	1,262	[4]	302	[4]	7,454	[4]	587	[4]
Other	4,578		(934)		6,346		2,549
Premier Silica acquisition costs	1,190		0		2,173		0
Contingency and environmental accrual adjustments	(326)		1,587		702		2,882
Loss on extinguishment of debt	0		0		197		2,367
Total other expense	$ 30,651		$ 12,053		$ 54,258		$ 29,914

[1] Primarily represents firm transportation payments on excess pipeline capacity commitments.

[2] Primarily represents expenses attributable to the portion of Pioneer's contracted drilling rig rates that are above current market rates and idle drilling rig fees, neither of which are charged to joint operations.

[3] Primarily represents charges to terminate rig contracts that are not required to meet planned drilling activities.

[4] Represents valuation charges on excess materials and supplies inventories; principally related to dry gas assets.