Basis Of Presentation (Derivatives and Hedging) (Details) (Pioneer Southwest Ltip [Member])	6 Months Ended
Jun. 30, 2012
Pioneer Southwest Ltip [Member]
Derivative [Line Items]
Pioneer Southwest's credit-adjusted risk-free rate curve basis	LIBOR
Pioneer Southwest's credit-adjusted risk-free rate curve, spread on variable rate	1.625%

The reference rate for the variable rate of the interest rate derivative, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

No definition available.

Name:	us-gaap_DerivativeDescriptionOfVariableRateBasis
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration