Effective October 1, 2019, the Company adopted Topic 842 and recorded ROU assets and lease liabilities of $154.6 million and $141.9 million, respectively. As part of the adoption, prepaid aircraft rent, deferred rent credits and accrued aircraft rents of $35.8 million, $21.3 million and $1.8 million, respectively, were classified as a component of the Company’s ROU assets.

As of December 31, 2020, the Company leased 18 aircraft, airport facilities, office space, and other property and equipment under non-cancelable operating leases. 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. The Company expects that, in the normal course of business, such operating leases that expire will be renewed or replaced by other leases, or the property may be purchased rather than leased. Aggregate rental expense under all operating aircraft, equipment and facility leases totaled approximately $13.8 million and $16.8 million for the three months ended December 31, 2020 and 2019, respectively.

As of December 31, 2020, the Company’s operating lease right-of-use assets were $114.7 million, the Company’s current maturities of operating lease liabilities were $44.7 million, and the Company’s noncurrent lease liabilities were $53.6 million.

The Company’s operating lease payments in operating cash flows for the three months ended December 31, 2020 and 2019 are $9.3 million and $9.5 million, respectively.

The table below presents lease related terms and discount rates as of December 31, 2020:

As of December 31,2020

Weighted average remaining lease term Operating

leases

3.3 years

Weighted average discount rate Operating leases

4.2

The Table below represents lease expense recorded during three months ended December 31, 2020 and 2019.

	Three Months Ended December 31,
	2020		2019		$ Change			% Change
Operating lease cost	$	13,839	$	16,784	$	(2,945	)		(17.5	)%

The following table summarizes future minimum rental payments primarily related to leased aircraft required under operating leases that had initial or remaining non-cancelable lease terms as of December 31, 2020 (in thousands):

Periods Ending December 31,	Total Maturities
Remainder of 2021	$	38,095
2022		33,242
2023		15,973
2024		14,682
2025		1,494
Thereafter		160
Less: Interest	$	(5,364	)
Amounts recorded in the Consolidated Balance Sheet	$	98,282

The following represents future minimum lease obligations under non-cancelable operating leases as of September 30, 2019 (in thousands):

Periods Ending September 30,	Total Payments
2020		47,814
2021		46,007
2022		31,090
2023		13,726
2024		13,185
Thereafter		1,368
Total	$	153,190

On October 8, 2020, the Company and General Electric Company (“GE”), acting through its GE-Aviation business unit, entered into an Amended and Restated Letter Agreement No. 13, which deferred the initial delivery and payment dates of the 20 new spare CF34-8C5 engines that were subject to previously disclosed letter agreements between the Company and GE. Under the terms of the Amended and Restated Letter Agreement, the Company agreed to purchase and take delivery of the 20 new space CF34-8C5 engines commencing in May 2021, with the final spare engine to be delivered in December 2021. Payments are now due in five (5) separate tranches commencing in December 2020, and in February, April, May and June 2021. The total purchase commitment related to these engines is approximately $118.9 million. However, the parties continue to discuss modifying the number of spare engines to be purchased by the Company and timing of deliveries under the Amended and restated Letter Agreement No. 13.

If the Company fails to accept delivery of the spare engines when duly tendered, the Company may be assessed a minimum cancellation charge based on the engine price determined as of the date of scheduled engine delivery to the Company.