BENEFIT PLAN (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012 Years	Dec. 31, 2011	Dec. 31, 2010
Benefit Plan Disclosure [Abstract]
Eligible age for defined contribution 401(k) savings plan (in years)	21
Maximum employee contribution as a percentage of eligible earnings (as a percent)	75.00%
Percentage match of employee contribution (as a percent)	50.00%
Maximum percentage match of employee contribution as a percentage of qualified compensation (as a percent)	6.00%
Maximum contribution as a percentage of eligible earnings for plans outside United States (as a percent)	50.00%
Contribution by employer	$ 5.0	$ 2.8	$ 1.8

- Details

Name:	pcln_BenefitPlanDisclosureAbstract
Namespace Prefix:	pcln_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of matching contribution made by employer to defined contribution plan during the year.

+ References

No definition available.

+ Details

Name:	pcln_DefinedContributionPlanContributionsByEmployer
Namespace Prefix:	pcln_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents the percentage match of employee contribution to be contributed by employer for certain plans outside United States.

+ References

No definition available.

+ Details

Name:	pcln_DefinedContributionPlanEmployerContributionForeignPlansPercentageMatchOfEmployeeContribution
Namespace Prefix:	pcln_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the percentage of employee contributions matched by the entity up to 6% of qualified compensation.

+ References

No definition available.

+ Details

Name:	pcln_DefinedContributionPlanEmployerContributionPercentageMatchOfEmployeeContribution
Namespace Prefix:	pcln_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the maximum limit of employer contributions to an employee's defined contribution account as a percentage of the employee's qualified compensation.

+ References

No definition available.

+ Details

Name:	pcln_DefinedContributionPlanEmployerMaximumContributionPercentageOfQualifiedCompensation
Namespace Prefix:	pcln_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents maximum contribution to defined benefit plans as a percentage of eligible earnings of employee, subject to a statutorily prescribed annual limit.

+ References

No definition available.

+ Details

Name:	pcln_DefinedContributionPlanMaximumContributionsByPlanParticipantsPercentage
Namespace Prefix:	pcln_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the minimum age limit for participating in defined contribution plan covering certain U.S. employees.

+ References

No definition available.

+ Details

Name:	pcln_DefinedContributionPlanParticipantMinimumAge
Namespace Prefix:	pcln_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant