BASIS OF PRESENTATION details (Details) $ in Millions	Jun. 30, 2015 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Unamortized debt issuance expense, excluding revolving credit facilities	$ 32.6

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues, excluding revolving credit facilities. This does not include the amounts capitalized as part of the cost of the utility plant or asset. This represents the amount to be included as a contra-liability to issued debt instruments.

No definition available.

Name:	pcln_UnamortizedDebtIssuanceExpenseexcludingRevolvingCreditFacility
Namespace Prefix:	pcln_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant