XML 60 R44.htm IDEA: XBRL DOCUMENT
v3.20.4

Organization and Summary of Significant Accounting Policies - Property, Equipment and Furnishings and Restricted Cash (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019
Restricted Cash |  |
Security deposits | $ 19,522 | $ 20,569
WEST III Notes |  |
Restricted Cash |  |
Projected maintenance obligation period | 9 months |
Minimum amount of cash from maintenance reserve payments required to be held in restricted cash account | $ 10,000 |
WEST IV Notes |  |
Restricted Cash |  |
Projected maintenance obligation period | 10 months |
Minimum amount of cash from maintenance reserve payments required to be held in restricted cash account | $ 5,000 |
WEST V Notes |  |
Restricted Cash |  |
Projected maintenance obligation period | 12 months |
Minimum amount of cash from maintenance reserve payments required to be held in restricted cash account | $ 5,000 |
WEST III Notes, WEST IV Notes, and WEST V Notes |  |
Restricted Cash |  |
Projected maintenance obligation period for security deposit | 4 months |
Security deposits | $ 1,000 |
Minimum |  |
Property, Equipment and Furnishings |  |
Useful life of property, equipment and furnishings | 3 years |
Maximum |  |
Property, Equipment and Furnishings |  |
Useful life of property, equipment and furnishings | 37 years |

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_PropertyPlantAndEquipmentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
Name: | us-gaap_PropertyPlantAndEquipmentUsefulLife
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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

X
- Definition This element represents money paid in advance to protect the provider of a product or service, such as a lessor, against damage or nonpayment by the buyer or tenant (lessee) during the term of the agreement. Such damages may include physical damage to the property, theft of property, and other contractual breaches. Security deposits held may be interest or noninterest bearing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.15(a)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 + Details
Name: | us-gaap_SecurityDepositLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Represents the minimum amount of cash from maintenance reserve payments required to be held in a restricted cash account. + References No definition available. + Details
Name: | wlfc_MinimumCashFromMaintenanceReservePaymentsRequiredToBeHeldInRestrictedCashAccount
Namespace Prefix: | wlfc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Represents the maintenance obligation period for which cash reserve payments are held in the restricted cash account. + References No definition available. + Details
Name: | wlfc_ProjectedMaintenanceObligationPeriod
Namespace Prefix: | wlfc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the maintenance obligation period for which cash reserve payments are held in the restricted cash account for the purpose of security deposit. + References No definition available. + Details
Name: | wlfc_ProjectedMaintenanceObligationPeriodForSecurityDeposit
Namespace Prefix: | wlfc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_DebtInstrumentAxis=wlfc_WestIIINotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=wlfc_WESTIVNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=wlfc_WESTVNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=wlfc_WESTIIINotesWESTIVNotesAndWESTVNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |