Name:	pcln_DeferredTaxAssetsLiabilitiesNetClassificationAbstract
Namespace Prefix:	pcln
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

This element represents the Dutch statutory income tax rate.

+ Details

Name:	pcln_DutchStatutoryIncomeTaxRate
Namespace Prefix:	pcln
Data Type:	us-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the effective income tax rate on qualifying innovative activities under Innovative Box Tax.

+ Details

Name:	pcln_EffectiveIncomeTaxRateAtInnovationBoxTaxRate
Namespace Prefix:	pcln
Data Type:	us-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents expected reduction in consolidated income tax rate.

+ Details

Name:	pcln_EffectiveIncomeTaxRateReconciliationReductionInEnactedTaxRate
Namespace Prefix:	pcln
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the amount of additional federal tax benefits related to equity transactions that are not included in deferred tax assets.

+ Details

Name:	pcln_ExcessTaxCreditsEquityTransactions
Namespace Prefix:	pcln
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	pcln_IncomeTaxesDisclosureAbstract
Namespace Prefix:	pcln
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	pcln_OperatingLossAndOtherTaxCarryforwardsLineItems
Namespace Prefix:	pcln
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The total estimated aggregate NOL, net of limitation, imposed by Section 382 related to the use of all operating loss carryforwards available to reduce future taxable income in the event of a more than 50 percent change in ownership.

+ Details

Name:	pcln_OperatingLossCarryforwardsLimitationsOnUseEstimatedFutureAggregateLimitation
Namespace Prefix:	pcln
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The limitation imposed by Section 382 related to the use of all operating loss carryforwards available to reduce future taxable income in the event of a more than 50 percent change in ownership.

+ Details

Name:	pcln_OperatingLossCarryforwardsLimitationsOnUseMinimumPercentageOwnershipChange
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Data Type:	us-types:percentItemType
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Period Type:	duration

- Definition

This element represents the period of time applicable to eligibility for Innovation Box Tax treatment. The entity must apply for and receive a certificate every period that the entity intends to be engaged in innovative activities for the subsequent period.

+ Details

Name:	pcln_PeriodOfTimeEligibilityForInnovationBoxTax
Namespace Prefix:	pcln
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The aggregate tax effects as of the balance sheet date of all future tax deductions arising from temporary differences between tax basis and generally accepted accounting principles basis recognition of assets, liabilities, revenues and expenses, which can only be deducted for tax purposes when permitted under enacted tax laws; net of deducting the allocated valuation allowance, if any, to reduce such amount to net realizable value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 43

+ Details

Name:	us-gaap_DeferredTaxAssetsNet
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the noncurrent portion of deferred tax liabilities, which result from applying the applicable tax rate to net taxable temporary differences pertaining to each jurisdiction to which the entity is obligated to pay income tax. A noncurrent taxable temporary difference is a difference between the tax basis and the carrying amount of a noncurrent asset or liability in the financial statements prepared in accordance with generally accepted accounting principles. In a classified statement of financial position, an enterprise shall separate deferred tax liabilities and assets into a current amount and a noncurrent amount. Deferred tax liabilities and assets shall be classified as current or noncurrent based on the classification of the related asset or liability for financial reporting. A deferred tax liability or asset that is not related to an asset or liability for financial reporting, including deferred tax assets related to carryforwards, shall be classified according to the expected reversal date of the temporary difference.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 41, 42

+ Details

Name:	us-gaap_DeferredTaxLiabilitiesNoncurrent
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate shall be the regular tax rate if there are alternative tax systems.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 47

+ Details

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Namespace Prefix:	us-gaap
Data Type:	us-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The sum of domestic, foreign and state and local operating loss carryforwards, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 48
-Subparagraph a

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The expiration date of each operating loss carryforward included in total operating loss carryforwards, or the applicable range of such expiration dates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 48
-Subparagraph a

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The gross amount of decreases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 48
-Paragraph 21
-Subparagraph a(1)

+ Details

Name:	us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

INCOME TAXES (Details) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
INCOME TAXES (Details) (USD $)	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011 Years Months	Jun. 30, 2010	Dec. 31, 2010
INCOME TAXES
U.S. statutory rate (as a percent)	35.00%	35.00%	35.00%	35.00%
Reversal of reserve for unrecognized tax benefits attributable to tax positions taken in 2010	$ 12,500,000
Effective income tax rate on qualifying innovative activities at Innovation Box Tax rate (as a percent)			5.00%		5.00%
Dutch statutory rate (as a percent)			25.00%
Period of time, eligibility for Innovation Box Tax (in months)			6
Reduction in consolidated income tax rate			two to four percentage
Operating Loss and Other Tax Carryforwards
Federal tax deductions related to equity transactions not included in deferred tax assets					87,800,000
Deferred Tax Assets (Liabilities), Net Classification
Deferred tax asset, net of valuation allowance recorded	210,500,000		210,500,000		222,000,000
Deferred income taxes	54,679,000		54,679,000		56,440,000
U.S. Federal Income Tax
Operating Loss and Other Tax Carryforwards
Net operating loss carryforwards					2,700,000,000
Maximum change in ownership percentage allowed before statutory limitations imposed on the availability of net operating losses (as a percent)			50.00%
Estimated aggregate limitation of cumulative net operating losses available net of limit imposed by IRC Section 382					1,300,000,000
U.S. Federal Income Tax \| Operating Losses
Operating Loss and Other Tax Carryforwards
Net operating loss carryforwards					600,000,000
Estimated aggregate limitation of cumulative net operating losses available net of limit imposed by IRC Section 382					600,000,000
U.S. Federal Income Tax \| Equity-Related Transactions
Operating Loss and Other Tax Carryforwards
Net operating loss carryforwards					2,100,000,000
Estimated aggregate limitation of cumulative net operating losses available net of limit imposed by IRC Section 382					$ 700,000,000
U.S. Federal Income Tax \| Subject To Statutory Limitation
Operating Loss and Other Tax Carryforwards
Net operating loss carryforwards - expiration dates					December 31, 2019 to December 31, 2021