INCOME TAXES Income Taxes (Details) (Trunkline LNG [Member], USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2014
Trunkline LNG [Member]
Income Tax Expense (Benefit)	$ 81

The amount of incremental income taxes incurred related to a transaction.

No definition available.

Name:	pepl_IncrementalIncomeTaxRelatedtoaTransaction
Namespace Prefix:	pepl_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration