Employee Benefit Plans (Narrative) (Details) (USD $) In Millions	6 Months Ended
Jun. 30, 2011
Employee Benefit Plans
Dominion contribution	$ 0
Expected contribution to voluntary employees' beneficiary association	$ 18

Name:

us-gaap_DefinedBenefitPlanEstimatedFutureEmployerContributionsInCurrentFiscalYear

Namespace Prefix:

us-gaap

Data Type:

xbrli:monetaryItemType

Balance Type:

debit

Period Type:

instant