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Debt Obligations - Schedule of Notes Payable (Details) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Long Term Debt |  |  |
Gross amount of debt | $ 1,758,191,000 |  | $ 1,827,059,000
Less: unamortized debt issuance costs and note discounts | (22,621,000) |  | (24,178,000)
Total debt obligations | 1,735,570,000 |  | 1,802,881,000
Revolving credit facility | Maturity in June 2024 |  |  |
Long Term Debt |  |  |
Line of credit facility, maximum borrowing capacity | 158,200,000 |  |
Revolving credit facility | Maturity in June 2025 |  |  |
Long Term Debt |  |  |
Line of credit facility, maximum borrowing capacity | 500,000,000.0 |  |
Credit facility at a floating rate of interest of one-month term Secured Overnight Financing Rate (“SOFR”) plus 3.00% and 1.38% on $218.8 million and $71.2 million, respectively, at March 31, 2024, secured by engines. The facility has a committed amount of $658.2 million at March 31, 2024, of which $158.2 million revolves until the maturity date of June 2024, and $500.0 million revolves until the maturity date of June 2025. |  |  |
Long Term Debt |  |  |
Line of credit facility outstanding amount | $ 290,000,000 |  | 353,000,000
WEST VII Series A 2023 term notes payable at a fixed rate of interest of 8.00%, maturing in October 2048, secured by engines |  |  |
Long Term Debt |  |  |
Fixed rate (as a percent) | 8.00% |  |
Gross amount of debt | $ 396,931,000 |  | 406,894,000
WEST VI Series A 2021 term notes payable at a fixed rate of interest of 3.10%, maturing in May 2046, secured by engines |  |  |
Long Term Debt |  |  |
Fixed rate (as a percent) | 3.10% |  |
Gross amount of debt | $ 250,544,000 |  | 252,986,000
WEST VI Series B 2021 term notes payable at a fixed rate of interest of 5.44%, maturing in May 2046, secured by engines |  |  |
Long Term Debt |  |  |
Fixed rate (as a percent) | 5.44% |  |
Gross amount of debt | $ 34,831,000 |  | 35,142,000
WEST VI Series C 2021 term notes payable at a fixed rate of interest of 7.39%, maturing in May 2046, secured by engines |  |  |
Long Term Debt |  |  |
Fixed rate (as a percent) | 7.39% |  |
Gross amount of debt | $ 11,781,000 |  | 12,361,000
WEST V Series A 2020 term notes payable at a fixed rate of interest of 3.23%, maturing in March 2045, secured by engines |  |  |
Long Term Debt |  |  |
Fixed rate (as a percent) | 3.23% |  |
Gross amount of debt | $ 236,642,000 |  | 240,371,000
WEST V Series B 2020 term notes payable at a fixed rate of interest of 4.21%, maturing in March 2045, secured by engines |  |  |
Long Term Debt |  |  |
Fixed rate (as a percent) | 4.21% |  |
Gross amount of debt | $ 32,966,000 |  | 33,485,000
WEST V Series C 2020 term notes payable at a fixed rate of interest of 6.66%, maturing in March 2045, secured by engines |  |  |
Long Term Debt |  |  |
Fixed rate (as a percent) | 6.66% |  |
Gross amount of debt | $ 10,043,000 |  | 10,695,000
WEST IV Series A 2018 term notes payable at a fixed rate of interest of 4.75%, maturing in September 2043, secured by engines |  |  |
Long Term Debt |  |  |
Fixed rate (as a percent) | 4.75% |  |
Gross amount of debt | $ 209,079,000 |  | 212,157,000
WEST IV Series B 2018 term notes payable at a fixed rate of interest of 5.44%, maturing in September 2043, secured by engines |  |  |
Long Term Debt |  |  |
Fixed rate (as a percent) | 5.44% |  |
Gross amount of debt | $ 28,602,000 |  | 29,024,000
WEST III Series A 2017 term notes payable at a fixed rate of interest of 4.69%, maturing in August 2042, secured by engines |  |  |
Long Term Debt |  |  |
Fixed rate (as a percent) | 4.69% |  |
Gross amount of debt | $ 171,760,000 |  | 175,705,000
WEST III Series B 2017 term notes payable at a fixed rate of interest of 6.36%, maturing in August 2042, secured by engines |  |  |
Long Term Debt |  |  |
Fixed rate (as a percent) | 6.36% |  |
Gross amount of debt | $ 23,062,000 |  | 23,592,000
Note payable at a fixed rate of interest of $5.00%, maturing in February 2033, secured by an engine |  |  |
Long Term Debt |  |  |
Fixed rate (as a percent) | 5.00% |  |
Gross amount of debt | $ 20,980,000 |  | 0
Note payable at a fixed rate of interest of 4.59%, maturing in November 2032, secured by an engine |  |  |
Long Term Debt |  |  |
Fixed rate (as a percent) | 4.59% |  |
Gross amount of debt | $ 22,483,000 |  | 22,610,000
Note payable at a fixed rate of interest of $4.23%, maturing in June 2032, secured by an engine |  |  |
Long Term Debt |  |  |
Fixed rate (as a percent) | 4.23% |  |
Gross amount of debt | $ 17,780,000 |  | 17,802,000
Note payable at a fixed rate of interest of 3.18%, maturing in July 2024, secured by an aircraft |  |  |
Long Term Debt |  |  |
Fixed rate (as a percent) | 3.18% |  |
Gross amount of debt | $ 707,000 |  | 1,235,000
Revolving credit facility | Credit facility at a floating rate of interest of one-month term Secured Overnight Financing Rate (“SOFR”) plus 3.00% and 1.38% on $218.8 million and $71.2 million, respectively, at March 31, 2024, secured by engines. The facility has a committed amount of $658.2 million at March 31, 2024, of which $158.2 million revolves until the maturity date of June 2024, and $500.0 million revolves until the maturity date of June 2025. |  |  |
Long Term Debt |  |  |
Line of credit facility, maximum borrowing capacity | 658,200,000 |  |
SOFR | Credit facility at a floating rate of interest of one-month term Secured Overnight Financing Rate (“SOFR”) plus 3.00% and 1.38% on $218.8 million and $71.2 million, respectively, at March 31, 2024, secured by engines. The facility has a committed amount of $658.2 million at March 31, 2024, of which $158.2 million revolves until the maturity date of June 2024, and $500.0 million revolves until the maturity date of June 2025. |  |  |
Long Term Debt |  |  |
Line of credit facility, maximum borrowing capacity | $ 218,800,000 |  | $ 71,200,000
Variable rate (as a percent) | 3.00% | 1.38% |

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