XML 58 R72.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Additional Information with Respect to Non-vested Options (Detail) (Employee Stock Option, USD $) In Millions, unless otherwise specified | Dec. 31, 2011 Year
--- | ---
Employee Stock Option |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Aggregate intrinsic value | $ 3.3
Weighted-average remaining contractual term | 8.56
Weighted-average remaining expected term | 3.45
Weighted-average remaining vesting period | 1.52
Unrecognized compensation cost | $ 6.7

X
- Definition Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Remaining Vesting Term + References No definition available. + Details
Name: | pten_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageRemainingVestingTerm
Namespace Prefix: | pten_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Share Based Compensation Arrangement by Share Based Payment Award, Options, Expected to Vest, Aggregate Intrinsic Value + References No definition available. + Details
Name: | pten_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpectedToVestAggregateIntrinsicValue
Namespace Prefix: | pten_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Share Based Compensation Arrangement By Share Based Payment Award Options Expected To Vest Weighted Average Remaining Contractual Term 1 + References No definition available. + Details
Name: | pten_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpectedToVestWeightedAverageRemainingContractualTerm1
Namespace Prefix: | pten_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Share Based Compensation Arrangement By Share Based Payment Award Options Expected To Vest Weighted Average Remaining Expected Term + References No definition available. + Details
Name: | pten_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpectedToVestWeightedAverageRemainingExpectedTerm
Namespace Prefix: | pten_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph h -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration