Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net income	$ 2,298us-gaap_NetIncomeLoss	$ 4,331us-gaap_NetIncomeLoss
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization expense	17,705us-gaap_DepreciationAndAmortization	15,710us-gaap_DepreciationAndAmortization
Write-down of equipment	24	295
Stock-based compensation expenses	1,074us-gaap_ShareBasedCompensation	758us-gaap_ShareBasedCompensation
Amortization of deferred costs	1,072us-gaap_AmortizationOfDeferredCharges	1,036us-gaap_AmortizationOfDeferredCharges
Amortization of interest rate derivative cost		(125)
Allowances and provisions	67	2
Gain on sale of leased equipment	(662)	(231)
Gain on debt extinguishment	(1,151)
Income from joint ventures	354	305
Deferred income taxes	1,357	2,405
Changes in assets and liabilities:
Receivables	(5,751)	(366)
Spare parts inventory	305us-gaap_IncreaseDecreaseInInventories	(428)us-gaap_IncreaseDecreaseInInventories
Other assets	(2,237)	(501)
Accounts payable and accrued expenses	(917)	1,734
Restricted cash	5,642	(8,068)
Maintenance reserves	3,198	2,416
Security deposits	(98)	(357)
Unearned lease revenue	(961)	493
Net cash provided by operating activities	20,611	18,799
Cash flows from investing activities:
Proceeds from sale of equipment (net of selling expenses)	2,405	5,688
Restricted cash for investing activities		5,487
Capital contribution to joint ventures	(630)
Purchase of equipment held for operating lease and for sale	(17,944)	(7,915)
Purchase of property, equipment and furnishings	(3,667)	(156)
Net cash used in investing activities	(19,836)	3,104
Cash flows from financing activities:
Proceeds from issuance of notes payable	31,000	5,000
Debt issuance cost		(27)us-gaap_PaymentsOfDebtIssuanceCosts
Interest bearing security deposits		1,518wlfc_ProceedsFromSecurityDeposit
Proceeds from shares issued under stock compensation plans	85	212
Cancellation of restricted stock units in satisfaction of withholding tax	(514)	(270)
Excess tax benefit from stock-based compensation	143
Repurchase of common stock	(724)
Principal payments on notes payable	(28,623)us-gaap_RepaymentsOfLongTermDebt	(25,506)us-gaap_RepaymentsOfLongTermDebt
Net cash provided by (used in) financing activities	1,367	(19,073)
Increase (decrease) in cash and cash equivalents	2,142	2,830
Cash and cash equivalents at beginning of period	13,493	12,801
Cash and cash equivalents at end of period	15,635	15,631
Net cash paid for:
Interest	8,753us-gaap_InterestPaidNet	8,811us-gaap_InterestPaidNet
Income Taxes	5us-gaap_IncomeTaxesPaidNet	55us-gaap_IncomeTaxesPaidNet
Supplemental disclosures of non-cash investing activities:
Purchase of aircraft and engines, liability incurred but not paid	169	802
Engines and equipment, transferred from Held for Operating Lease to Held for Sale but not settled	$ 86	$ 10,924

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-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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- Definition

The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

+ References

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- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

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- Definition

The cash inflow associated with the amount received from holders to acquire the entity's shares under incentive and share awards other than stock option exercises. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

+ References

No definition available.

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- Definition

The cash inflow from sale of machinery and equipment.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

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- Definition

The cash inflow associated with the sale of investments that are pledged or subject to withdrawal restrictions during the period.

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- Definition

Nonrecurring impairment charges related to the write-off of production-related equipment and inventory. This tag is used when an Entity charges this cost to cost of goods sold.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.2(a))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 11

-Article 9

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.11)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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- Definition

Value of loans and leases held in the entity's portfolio transferred to loans and leases held-for-sale in noncash transactions.

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- Definition

A liability for future maintenance events that have a refundable aspect contingent on return conditions.

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No definition available.

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Balance Type:	na
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- Definition

Represents the cash inflow related to security deposit.

+ References

No definition available.

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