XML 24 R50.htm IDEA: XBRL DOCUMENT
v2.4.0.8

SHARE-BASED COMPENSATION PLAN (Details) (USD $) In Millions, except Share data, unless otherwise specified |  |  |  | 12 Months Ended |  | 12 Months Ended | 3 Months Ended | 0 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2013 Equity Incentive Plan 2011 [Member] Person | Dec. 31, 2012 Equity Incentive Plan 2011 [Member] | Dec. 31, 2011 Equity Incentive Plan 2011 [Member] Person | Jan. 10, 2013 Equity Incentive Plan 2011 [Member] | Dec. 31, 2011 Equity Incentive Plan 2011 [Member] Minimum [Member] | Dec. 31, 2011 Equity Incentive Plan 2011 [Member] Maximum [Member] | Dec. 31, 2012 Scandic American Shipping Ltd. [Member] | Dec. 31, 2013 Employees [Member] | Dec. 31, 2012 Employees [Member] | Dec. 31, 2013 Non-Employees [Member] | Dec. 31, 2012 Non-Employees [Member] | Dec. 31, 2013 Employees and Non Employees [Member] | Dec. 31, 2013 Employees and Non Employees [Member] Equity Incentive Plan 2011 [Member] | Dec. 31, 2012 Employees and Non Employees [Member] Equity Incentive Plan 2011 [Member] | Dec. 31, 2012 Restricted Stock Awards [Member] Scandic American Shipping Ltd. [Member] | Mar. 31, 2013 Restricted Stock Awards [Member] Scandic American Shipping Ltd. [Member] Equity Incentive Plan 2011 [Member] | Aug. 05, 2011 Restricted Stock Awards [Member] Employees and Non Employees [Member] Equity Incentive Plan 2011 [Member] | Feb. 23, 2011 Restricted Stock Awards [Member] Employees and Non Employees [Member] Equity Incentive Plan 2011 [Member] | Dec. 31, 2013 Restricted Stock Awards [Member] Employees and Non Employees [Member] Equity Incentive Plan 2011 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Manager's right to ownership of company's total outstanding shares (in hundredths) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.00% |  |  |  |
Common Stock, par value (in dollars per share) | $ 0.01 | $ 0.01 | $ 0.01 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.01 |  |  |  |
Number of shares transferred in acquisition (in shares) |  |  |  |  |  |  |  |  |  | 1,910,112 |  |  |  |  |  |  |  |  |  |  |  |
Lock up period of new shares issued to the Manager |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 year |  |  |  |
Vesting requirement lifted for restricted shares |  |  |  |  |  |  | 174,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of allocated shares to outstanding shares (in hundredths) |  |  |  |  |  | 0.80% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restricted shares remaining in plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 203,000 |  |  |  |  |  |
Fair value of shares issued to manager (in dollars per share) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 13.73 |  | $ 18.05 | $ 23.88 |
Acquisition of shares in percentage (in hundredths) |  |  |  |  |  |  |  |  |  | 100.00% |  |  |  |  |  |  |  |  |  |  |  |
Total compensation cost for the period |  |  |  | $ 2.1 | $ 1.3 | $ 1.3 |  |  |  |  |  |  |  |  |  |  |  |  | $ 1.1 |  |  |
Restricted shares authorized (in shares) |  |  |  | 400,000 |  | 400,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Individuals in management and Board members participating in incentive plan |  |  |  | 17 |  | 23 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares held in treasury (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 23,000 | 14,500 | 8,500 |  |  |  |  |
Share-based compensation arrangement shares cliff vesting period |  |  |  |  |  |  |  | 4 years | 5 years |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation arrangement shares authorized and issued, first range (in shares) |  |  |  |  |  | 326,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation arrangement shares authorized and issued, second range (in shares) |  |  |  |  |  | 74,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unrecognized compensation cost related to unvested restricted stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1.1
Weighted average period to recognize the unrecognized compensation cost |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 year 1 month 2 days
Fair value of shares vested |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1.7
Restricted shares -Employees and Non-Employees [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Non-vested at beginning of period (in shares) |  |  |  |  |  |  |  |  |  |  | 163,000 | 163,000 | 228,500 | 237,000 |  |  |  |  |  |  |  |
Granted during the year (in shares) |  |  |  | 203,000 |  | 400,000 |  |  |  |  | 0 | 0 | 0 | 0 |  |  |  | 112,245 |  | 74,000 | 326,000 |
Vested during the year (in shares) |  |  |  |  |  |  |  |  |  |  | 0 | 0 | (174,000) | 0 |  |  |  |  |  |  |  |
Forfeited during the year (in shares) |  |  |  |  |  |  |  |  |  |  | 0 | 0 | (14,500) | (8,500) |  |  |  |  |  |  |  |
Non-vested at end of period (in shares) |  |  |  |  |  |  |  |  |  |  | 163,000 | 163,000 | 40,000 | 228,500 |  |  |  |  |  |  |  |
Weighted-average grant-date fair value [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Non-vested at beginning of period (in dollars per share) |  |  |  |  |  |  |  |  |  |  | $ 23.88 | $ 23.88 | $ 22.06 | $ 22.06 |  |  |  |  |  |  |  |
Granted during the year (in dollars per share) |  |  |  |  |  |  |  |  |  |  | $ 0 | $ 0 | $ 0 | $ 0 |  |  |  |  |  |  |  |
Vested during the year (in dollars per share) |  |  |  |  |  |  |  |  |  |  | $ 0 | $ 0 | $ 0 | $ 0 |  |  |  |  |  |  |  |
Forfeited during the year (in dollars per share) |  |  |  |  |  |  |  |  |  |  | $ 0 | $ 0 | $ 0 | $ 0 |  |  |  |  |  |  |  |
Non-vested at end of period (in dollars per share) |  |  |  |  |  |  |  |  |  |  | $ 23.88 | $ 23.88 | $ 24.84 | $ 22.06 |  |  |  |  |  |  |  |

X
- Definition Factor defining the numbers of common shares the manager is entitled upon qualifying events (e.g. initial adoption of management agreement and subsequent share issues). + References No definition available. + Details
Name: | nat_DueToRelatedPartiesManagersRightToOwnershipOfCompanysTotalOutstandingShares
Namespace Prefix: | nat_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of individual in management and Board members participating in incentive plan. + References No definition available. + Details
Name: | nat_IndividualsInManagementandBoardParticipatingInIncentivePlan
Namespace Prefix: | nat_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Period for which the shares issued are non-transferable. + References No definition available. + Details
Name: | nat_LockUpPeriod
Namespace Prefix: | nat_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the percentage of allocated shares to outstanding shares. + References No definition available. + Details
Name: | nat_PercentageOfAllocatedSharesToOutstandingShares
Namespace Prefix: | nat_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of balance sheet date. + References No definition available. + Details
Name: | nat_ShareBasedCompensationArrangementsByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingNumber
Namespace Prefix: | nat_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition The first range of awards issued under the equity-based compensation plan, within the maximum number of shares authorized for share-based compensation plan. + References No definition available. + Details
Name: | nat_ShareBasedCompensationArrangementSharesAuthorizedAndIssuedFirstRange
Namespace Prefix: | nat_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The second range of awards issued under the equity-based compensation plan, within the maximum number of shares authorized for share-based compensation plan. + References No definition available. + Details
Name: | nat_ShareBasedCompensationArrangementSharesAuthorizedAndIssuedSecondRange
Namespace Prefix: | nat_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The fair value per share of shares issued during the period under a share based compensation arrangement. + References No definition available. + Details
Name: | nat_ShareBasedCompensationFairValueOfSharesIssued
Namespace Prefix: | nat_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of restricted shares for which requirements have been lifted. + References No definition available. + Details
Name: | nat_VestingRequirementLiftedForRestrictedShares
Namespace Prefix: | nat_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | nat_WeightedAverageGrantDateFairValueAbstract
Namespace Prefix: | nat_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 14.F) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 14 -Section F + Details
Name: | us-gaap_AllocatedShareBasedCompensationExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Number of shares of equity interests issued or issuable to acquire entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b)(4) -URI http://asc.fasb.org/extlink&oid=7488404&loc=d3e6927-128479 + Details
Name: | us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of voting equity interests acquired at the acquisition date in the business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463 + Details
Name: | us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Face amount or stated value per share of common stock. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 30 -Article 5 + Details
Name: | us-gaap_CommonStockParOrStatedValuePerShare
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Unrecognized cost of unvested share-based compensation awards. + References Reference 1: 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
- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: 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_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

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

X
- Definition The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

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

X
- Definition The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of shares that have been repurchased during the period and are being held in treasury. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 + Details
Name: | us-gaap_TreasuryStockSharesAcquired
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration