Summary of Significant Accounting Policies (Policies)	6 Months Ended
Jun. 30, 2020
Accounting Policies [Abstract]
Organization and Basis of Presentation	Aircastle Limited (“Aircastle,” the “Company,” “we,” “us” or “our”) is a Bermuda exempted company that was incorporated on October 29, 2004 under the provisions of Section 14 of the Companies Act of 1981 of Bermuda. Aircastle’s business is acquiring, leasing, managing and selling commercial jet aircraft.
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include the accounts of Aircastle and all its subsidiaries. Aircastle consolidates two Variable Interest Entities (“VIEs”) of which Aircastle is the primary beneficiary. All intercompany transactions and balances have been eliminated in consolidation. We consolidate VIEs in which we have determined that we are the primary beneficiary. We use judgment when deciding: (a) whether an entity is subject to consolidation as a VIE; (b) who the variable interest holders are; (c) the potential expected losses and residual returns of the variable interest holders; and (d) which variable interest holder is the primary beneficiary. When determining which enterprise is the primary beneficiary, we consider: (1) the entity’s purpose and design; (2) which variable interest holder has the power to direct the activities that most significantly impact the entity’s economic performance; and (3) the obligation to absorb losses of the entity or the right to receive benefits from the entity that could potentially be significant to the VIE. When certain events occur, we reconsider whether we are the primary beneficiary of VIEs. We do not reconsider whether we are a primary beneficiary solely because of operating losses incurred by an entity.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. While Aircastle believes the estimates and related assumptions used in the preparation of the consolidated financial statements are appropriate, actual results could differ from those estimates.
Revenue Recognition Leases, Operating [Policy Text Block]	Lease Revenue Recognition We lease flight equipment under net operating leases with lease terms typically ranging from three to seven years. We generally do not offer renewal terms or purchase options in our leases, although certain of our operating leases allow the lessee the option to extend the lease for an additional term. Operating leases with fixed rentals and step rentals are recognized on a straight-line basis over the term of the initial lease, assuming no renewals. Operating lease rentals that adjust based on a London Interbank Offered Rate (“LIBOR”) index are recognized on a straight-line basis over the lease term using the prevailing rate at lease commencement. Changes to rate-based lease rentals are recognized in the statements of income (loss) in the period of change. In certain instances, we may provide lease concessions to customers, generally in the form of lease rental deferrals. While these deferral arrangements affect the timing of lease rental payments, the total amount of lease rental payments required over the lease term is generally the same as that which was required under the original lease agreement. We account for the deferrals as if no modifications to the lease agreements were made and record the deferred rentals as a receivable within Other assets in our consolidated balance sheet. If we determine that the collectability of rental payments is no longer probable (including any deferral thereof), we recognize lease rental revenue using a cash basis of accounting rather than an accrual method. In the period we conclude that collection of lease payments is no longer probable, we recognize any difference between revenue amounts recognized to date under the accrual method and payments that have been collected from the lessee, including security deposit amounts held, as a current period adjustment to lease rental revenue. The COVID-19 virus has had an unprecedented negative impact on the global economy, and in particular on the aviation sector. There has been a dramatic slowdown in air traffic, with many markets in near complete shutdown. According to the International Air Transport Association (“IATA”), as of mid-June 2020, air travel is down to approximately 30% of normal levels and a full recovery to pre-pandemic levels is not expected for several years. Substantially all the world’s airlines are experiencing financial difficulties and liquidity challenges. While we believe the long-term demand for air travel will return to historical trends over time, the near-term impacts of the COVID-19 virus’ economic shock are material; the extent and duration of which cannot currently be determined. Airlines have been seeking to preserve liquidity through a combination of requesting government support, raising debt and equity, delaying or canceling new aircraft orders, furloughing employees, as well as requesting deferrals from lessors. We have agreed to defer near-term lease payments with certain of our airline customers, which they are obliged to repay over time. As of August 1, 2020, we have agreed to defer approximately $99,000 in near-term lease payments, including $61,209 that appear in our Consolidated Balance Sheet as components of Accounts receivable, Net investment in leases, or Other assets as of June 30, 2020. This represents approximately 12% of Lease rental and Direct financing and sales-type lease revenues for the twelve months ended June 30, 2020. Deferrals have been agreed to with 40 airlines, representing 50% of our customer base, and for an average deferral of four months of lease rentals. In a limited number of situations, we have agreed to broader restructurings of contractual terms, for example obtaining better security packages, term extensions, or other valuable considerations in exchange for short-term economic concessions.
Financing Receivable, Held-for-investment [Policy Text Block]	Net Investment in Leases If a lease meets specific criteria at lease commencement or at the effective date of a lease modification, we recognize the lease as a direct financing or sales-type lease. The net investment in direct financing and sales-type leases consists of the lease receivable, estimated unguaranteed residual value of the lease flight equipment at lease-end and, for direct financing leases, deferred selling profit. For sales-type leases, we recognize the difference between the net book value of the aircraft and the net investment in the lease as a gain or loss on sale of flight equipment. Selling profit on a direct financing lease is deferred and amortized over the lease term, and a selling loss is recognized at lease commencement. Interest income on our net investment in leases is recognized as Direct financing and sales-type leases revenue over the lease term in a manner that produces a constant rate of return on the net investment in the lease. The net investment in leases is recorded in the consolidated financial statements net of an allowance for credit losses. The allowance for credit losses is recorded upon the initial recognition of the net investment in the lease based on the Company’s estimate of expected credit losses over the lease term. The allowance reflects the Company’s estimate of lessee default probabilities and loss given default percentages. When determining the credit loss allowance, we consider relevant information about past events, current conditions, and reasonable and supportable forecasts that affect the collectability of the net investment in the lease. The allowance also considers potential losses due to non-credit risk related to unguaranteed residual values. A provision for credit losses is recorded as a component of Selling, general, and administrative expenses in our Consolidated Statements of Income (Loss) to adjust the allowance for changes to management’s estimate of expected credit losses.
New Accounting Pronouncements, Policy	Recent Accounting Pronouncements In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848), Facilitation of the Effects of Reference Rate Reform on Financial Reporting. The standard applies to entities that have contracts, such as debt agreements, lease agreements or derivative instruments, which reference LIBOR or another reference rate expected to be discontinued due to reference rate reform. Entities can elect not to apply certain modification accounting requirements for contract modifications that replace a reference rate affected by reference rate reform. If elected, such contracts are accounted for as a continuation of the existing contract and no reassessments or re-measurements are required. The standard is effective for all entities from March 12, 2020 through December 31, 2022 and does not apply to contract modifications made after December 31, 2022. We have not adopted ASC 848 for this interim period and are currently evaluating the election available to us under the standard and the impact it may have on our financial statements. In April 2020, the FASB Staff issued a question-and-answer document (the “Q&A”) regarding accounting for lease concessions related to the effects of the COVID-19 pandemic. The Q&A provides that entities may elect to apply or not apply the lease modification guidance in ASC 842, “Leases”, for lease concessions provided by lessors as a result of the COVID-19 pandemic. The Company has elected not to apply the lease modification guidance in ASC 842 for such lease concessions – see “Lease Revenue Recognition” above.

Summary of Significant Accounting Policies (Policies)

6 Months Ended

Jun. 30, 2020

Aircastle Limited (“Aircastle,” the “Company,” “we,” “us” or “our”) is a Bermuda exempted company that was incorporated on October 29, 2004 under the provisions of Section 14 of the Companies Act of 1981 of Bermuda. Aircastle’s business is acquiring, leasing, managing and selling commercial jet aircraft.

Principles of Consolidation

The consolidated financial statements include the accounts of Aircastle and all its subsidiaries. Aircastle consolidates two Variable Interest Entities (“VIEs”) of which Aircastle is the primary beneficiary. All intercompany transactions and balances have been eliminated in consolidation.

We consolidate VIEs in which we have determined that we are the primary beneficiary. We use judgment when deciding: (a) whether an entity is subject to consolidation as a VIE; (b) who the variable interest holders are; (c) the potential expected losses and residual returns of the variable interest holders; and (d) which variable interest holder is the primary beneficiary. When determining which enterprise is the primary beneficiary, we consider: (1) the entity’s purpose and design; (2) which variable interest holder has the power to direct the activities that most significantly impact the entity’s economic performance; and (3) the obligation to absorb losses of the entity or the right to receive benefits from the entity that could potentially be significant to the VIE. When certain events occur, we reconsider whether we are the primary beneficiary of VIEs. We do not reconsider whether we are a primary beneficiary solely because of operating losses incurred by an entity.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. While Aircastle believes the estimates and related assumptions used in the preparation of the consolidated financial statements are appropriate, actual results could differ from those estimates.

Revenue Recognition Leases, Operating [Policy Text Block]

Lease Revenue Recognition

We lease flight equipment under net operating leases with lease terms typically ranging from three to seven years. We generally do not offer renewal terms or purchase options in our leases, although certain of our operating leases allow the lessee the option to extend the lease for an additional term. Operating leases with fixed rentals and step rentals are recognized on a straight-line basis over the term of the initial lease, assuming no renewals. Operating lease rentals that adjust based on a London Interbank Offered Rate (“LIBOR”) index are recognized on a straight-line basis over the lease term using the prevailing rate at lease commencement. Changes to rate-based lease rentals are recognized in the statements of income (loss) in the period of change.

In certain instances, we may provide lease concessions to customers, generally in the form of lease rental deferrals. While these deferral arrangements affect the timing of lease rental payments, the total amount of lease rental payments required over the lease term is generally the same as that which was required under the original lease agreement. We account for the deferrals as if no modifications to the lease agreements were made and record the deferred rentals as a receivable within Other assets in our consolidated balance sheet.

If we determine that the collectability of rental payments is no longer probable (including any deferral thereof), we recognize lease rental revenue using a cash basis of accounting rather than an accrual method. In the period we conclude that collection of lease payments is no longer probable, we recognize any difference between revenue amounts recognized to date under the accrual method and payments that have been collected from the lessee, including security deposit amounts held, as a current period adjustment to lease rental revenue.

The COVID-19 virus has had an unprecedented negative impact on the global economy, and in particular on the aviation sector. There has been a dramatic slowdown in air traffic, with many markets in near complete shutdown. According to the International Air Transport Association (“IATA”), as of mid-June 2020, air travel is down to approximately 30% of normal levels and a full recovery to pre-pandemic levels is not expected for several years. Substantially all the world’s airlines are experiencing financial difficulties and liquidity challenges. While we believe the long-term demand for air travel will return to historical trends over time, the near-term impacts of the COVID-19 virus’ economic shock are material; the extent and duration of which cannot currently be determined.

Airlines have been seeking to preserve liquidity through a combination of requesting government support, raising debt and equity, delaying or canceling new aircraft orders, furloughing employees, as well as requesting deferrals from lessors. We have agreed to defer near-term lease payments with certain of our airline customers, which they are obliged to repay over time. As of August 1, 2020, we have agreed to defer approximately $99,000 in near-term lease payments, including $61,209 that appear in our Consolidated Balance Sheet as components of Accounts receivable, Net investment in leases, or Other assets as of June 30, 2020. This represents approximately 12% of Lease rental and Direct financing and sales-type lease revenues for the twelve months ended June 30, 2020. Deferrals have been agreed to with 40 airlines, representing 50% of our customer base, and for an average deferral of four months of lease rentals. In a limited number of situations, we have agreed to broader restructurings of contractual terms, for example obtaining better security packages, term extensions, or other valuable considerations in exchange for short-term economic concessions.

Financing Receivable, Held-for-investment [Policy Text Block]

Net Investment in Leases

If a lease meets specific criteria at lease commencement or at the effective date of a lease modification, we recognize the lease as a direct financing or sales-type lease. The net investment in direct financing and sales-type leases consists of the lease receivable, estimated unguaranteed residual value of the lease flight equipment at lease-end and, for direct financing leases, deferred selling profit. For sales-type leases, we recognize the difference between the net book value of the aircraft and the net investment in the lease as a gain or loss on sale of flight equipment. Selling profit on a direct financing lease is deferred and amortized over the lease term, and a selling loss is recognized at lease commencement. Interest income on our net investment in leases is recognized as Direct financing and sales-type leases revenue over the lease term in a manner that produces a constant rate of return on the net investment in the lease.

The net investment in leases is recorded in the consolidated financial statements net of an allowance for credit losses. The allowance for credit losses is recorded upon the initial recognition of the net investment in the lease based on the Company’s estimate of expected credit losses over the lease term. The allowance reflects the Company’s estimate of lessee default probabilities and loss given default percentages. When determining the credit loss allowance, we consider relevant information about past events, current conditions, and reasonable and supportable forecasts that affect the collectability of the net investment in the lease. The allowance also considers potential losses due to non-credit risk related to unguaranteed residual values. A provision for credit losses is recorded as a component of Selling, general, and administrative expenses in our Consolidated Statements of Income (Loss) to adjust the allowance for changes to management’s estimate of expected credit losses.

New Accounting Pronouncements, Policy

Recent Accounting Pronouncements

In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848), Facilitation of the Effects of Reference Rate Reform on Financial Reporting. The standard applies to entities that have contracts, such as debt agreements, lease agreements or derivative instruments, which reference LIBOR or another reference rate expected to be discontinued due to reference rate reform. Entities can elect not to apply certain modification accounting requirements for contract modifications that replace a reference rate affected by reference rate reform. If elected, such contracts are accounted for as a continuation of the existing contract and no reassessments or re-measurements are required. The standard is effective for all entities from March 12, 2020 through December 31, 2022 and does not apply to contract modifications made after December 31, 2022. We have not adopted ASC 848 for this interim period and are currently evaluating the election available to us under the standard and the impact it may have on our financial statements.

In April 2020, the FASB Staff issued a question-and-answer document (the “Q&A”) regarding accounting for lease concessions related to the effects of the COVID-19 pandemic. The Q&A provides that entities may elect to apply or not apply the lease modification guidance in ASC 842, “Leases”, for lease concessions provided by lessors as a result of the COVID-19 pandemic. The Company has elected not to apply the lease modification guidance in ASC 842 for such lease concessions – see “Lease Revenue Recognition” above.