At September 30, 2019, the Company leased 18 aircraft under non-cancelable operating leases with remaining terms of up to 4.5 years. The Company has the option to terminate certain leases at various times throughout the lease. The Company headquarters and other facility non-cancelable operating leases have remaining terms of up to 6.2 years. The leases require the Company to pay all taxes, maintenance, insurance, and other operating expenses. Rental expense is recognized on a straight-line basis over the lease term, net of lessor rebates and other incentives. Aggregate rental expense under all operating aircraft, equipment and facility leases totaled approximately $72.8 million, $85.9 million and $83.8 million for the years ended September 30, 2019, 2018 and 2017, respectively.

Future minimum lease payments as of September 30, 2019, under non-cancelable operating leases are as follows (in thousands):

Periods Ending September 30,	Aircraft		Other		Total
2020	$	44,231	$	3,583	$	47,814
2021		44,314		1,693		46,007
2022		29,751		1,339		31,090
2023		12,418		1,308		13,726
2024		11,849		1,336		13,185
Thereafter		—		1,368		1,368
Total	$	142,563	$	10,627	$	153,190

The majority of the Company's leased aircraft are leased through trusts that have a sole purpose to purchase, finance, and lease these aircraft to the Company; therefore, they meet the criteria of a variable interest entity. However, since these are single-owner trusts in which the Company does not participate, the Company is not at risk for losses and is not considered the primary beneficiary. Management believes that the Company's maximum exposure under these leases is the remaining lease payments.