The remaining time until maturity of the debt instrument.

No definition available.

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Namespace Prefix:	al_
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Balance Type:	na
Period Type:	instant

- Definition

Line Of Credit Amount Maturing

+ References

No definition available.

+ Details

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Namespace Prefix:	al_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line Of Credit Facility, Maximum Borrowing Capacity, Increase (Decrease), Percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	al_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 20
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	instant

- 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

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Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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-Paragraph 1
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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Debt Financing - Narrative (Details) - USD ($)	12 Months Ended
Debt Financing - Narrative (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020	Jan. 31, 2022
Debt Instrument [Line Items]
Outstanding balance	$ 17,204,019,000	$ 16,696,081,000
Outstanding balance	17,022,480,000	16,518,338,000
Senior notes
Debt Instrument [Line Items]
Outstanding balance	$ 16,892,058,000	$ 15,583,544,000
Senior notes \| LIBOR
Debt Instrument [Line Items]
Interest margin	1.125%	1.125%
Senior notes \| Three Month London Interbank Offered Rate Libor
Debt Instrument [Line Items]
Interest margin	0.35%	0.67%
Senior notes \| Minimum
Debt Instrument [Line Items]
Remaining term	1 month
Interest rate	0.70%	2.25%
Senior notes \| Maximum
Debt Instrument [Line Items]
Remaining term	8 years 11 months 1 day
Interest rate	4.625%	4.625%
Medium Term Note Program \| Senior notes
Debt Instrument [Line Items]
Principal amount issued	$ 3,700,000,000
Medium Term Note Program, $750 Million, Due 2024 \| Senior notes
Debt Instrument [Line Items]
Interest rate	0.70%
Principal amount issued	$ 750,000,000
Medium Term Note Program, $1.2 Billion Due 2026 \| Senior notes
Debt Instrument [Line Items]
Interest rate	1.875%
Principal amount issued	$ 1,200,000,000
Medium Term Note Program, $600 Million, Due 2022 \| Senior notes
Debt Instrument [Line Items]
Interest rate	0.35%
Principal amount issued	$ 600,000,000
Medium Term Note Program, $600 Million, Due 2024 \| Senior notes
Debt Instrument [Line Items]
Interest rate	0.80%
Principal amount issued	$ 600,000,000
Medium Term Note Program, $500 Million, Due 2028 \| Senior notes
Debt Instrument [Line Items]
Interest rate	2.10%
Principal amount issued	$ 500,000,000
Medium Term Note Program Due 2027 \| Senior notes \| Subsequent Event
Debt Instrument [Line Items]
Interest rate			2.20%
Principal amount issued			$ 750,000,000
Medium Term Note Program Due 2032 \| Senior notes \| Subsequent Event
Debt Instrument [Line Items]
Interest rate			287.50%
Principal amount issued			$ 750,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Outstanding balance	$ 0	$ 0
Facility fee	0.20%
Maximum borrowing capacity	$ 6,800,000,000
Increase in maximum capacity from prior period	13.30%
Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Interest margin	1.05%
Revolving Credit Facility \| Base Rate
Debt Instrument [Line Items]
Interest margin	0.05%
Unsecured Revolving Credit Facility Mature May 5, 2025 \| Debt Instrument, Redemption, May 5, 2023
Debt Instrument [Line Items]
Line of credit maturity amount	$ 6,100,000,000
Unsecured Revolving Credit Facility Mature May 5, 2023 \| Debt Instrument, Redemption, May 5, 2022
Debt Instrument [Line Items]
Line of credit maturity amount	575,000,000
Unsecured Revolving Credit Facility Mature May 5, 2022 \| Debt Instrument, Redemption, May 5, 2021
Debt Instrument [Line Items]
Line of credit maturity amount	105,000,000
Other Debt Financings
Debt Instrument [Line Items]
Outstanding balance	$ 312,000,000	$ 1,100,000,000
Other Debt Financings \| Minimum
Debt Instrument [Line Items]
Debt term	3 months
Other Debt Financings \| Maximum
Debt Instrument [Line Items]
Debt term	7 years 9 months 18 days