XML 57 R41.htm IDEA: XBRL DOCUMENT
v3.3.1.900

Organization and Summary of Significant Accounting Policies (Organization and Revenue Recognition) (Details) - USD ($) |  | 12 Months Ended |
--- | --- | --- | ---
Sep. 18, 2013 | Dec. 31, 2015 | Sep. 16, 2013
Revenue Recognition |  |  |
Lease rent to be received, more than 30 days past due |  | $ 5,300,000 |
Maintenance reserve payments to be received, more than 30 days past due |  | $ 2,900,000 |
Minimum number of days for which lease rent and maintenance reserve payments are past due |  | 30 days |
Revenue | Customer concentration risk | One largest customer |  |  |
Organizations [Line Items] |  |  |
Percentage of concentration risk |  | 8.40% |
Lease rents due |  | $ 0 |
WOLF |  |  |
Organizations [Line Items] |  |  |
Previously held interest (as a percent) |  |  | 50.00%
Acquisition of the remaining outstanding shares (as a percent) | 50.00% |  |
Controlling interest assumed (as a percent) | 100.00% |  |
WOLF |  |  |
Organizations [Line Items] |  |  |
Previously held interest (as a percent) |  |  | 50.00%

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=56956515&loc=d3e1392-128463 + Details
Name: | us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage of equity in the acquiree held by the acquirer immediately before the acquisition date in a business combination. + References No definition available. + Details
Name: | us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6351-108592 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13531-108611 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6404-108592 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13537-108611 + Details
Name: | us-gaap_ConcentrationRiskPercentage1
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_RevenueRecognitionAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions. + References No definition available. + Details
Name: | us-gaap_SubsidiaryOrEquityMethodInvesteeCumulativePercentageOwnershipAfterAllTransactions
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the minimum number of days for which lease rent and maintenance reserve payments are past due. + References No definition available. + Details
Name: | wlfc_LeaseRentAndMaintenanceReservePaymentsReceivablePastDuePeriodMinimum
Namespace Prefix: | wlfc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the amount of maintenance reserve payments receivable that are more than 30 days past due. + References No definition available. + Details
Name: | wlfc_MaintenanceReservePaymentsReceivableOverThirtyDaysPastDue
Namespace Prefix: | wlfc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Represents the amount of lease rents receivable due to delinquency in rental payments by lessees. + References No definition available. + Details
Name: | wlfc_OperatingLeasesLeaseRentReceivable
Namespace Prefix: | wlfc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Represents the amount of lease rent receivables that are more than 30 days past due. + References No definition available. + Details
Name: | wlfc_OperatingLeasesLeaseRentReceivableOverThirtyDaysPastDue
Namespace Prefix: | wlfc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Organization [Line Items] + References No definition available. + Details
Name: | wlfc_OrganizationsLineItems
Namespace Prefix: | wlfc_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_SalesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CustomerConcentrationRiskMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorCustomersAxis=wlfc_OneLargestCustomerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=wlfc_WOLFA340LLCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=wlfc_WOLFA340LLCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |