Leases (Tables)

12 Months Ended

Dec. 31, 2020

Leases - Tables [Abstract]

Lease-Related Assets and Liabilities

Lease-related assets and liabilities recorded on the Consolidated Balance Sheet were as follows:

(in millions)	Balance Sheet location	December 31, 2020		December 31, 2019
Assets
Operating	Operating lease right-of-use assets (net)	$	1,892	$	1,349
Finance	Property and equipment (net of allowance for depreciation and amortization of $567 and $455)	667		779
Total lease assets		$	2,559	$	2,128
Liabilities
Current
Operating	Current operating lease liabilities	$	306	$	353
Finance	Current maturities of long-term debt	83		85
Noncurrent
Operating	Noncurrent operating lease liabilities	1,562		978
Finance	Long-term debt less current maturities	459		542
Total lease liabilities		$	2,410	$	1,958

Components of Lease Cost

The components of lease costs, included in the Consolidated Statement of Comprehensive Income (Loss), were as follows:

(in millions)	Statement of Comprehensive Income (Loss) location	Year ended December 31, 2020		Year ended December 31, 2019
Operating lease cost - aircraft (a)	Other operating expenses	$	216	$	182
Operating lease cost - other	Landing fees and airport rentals, and Other operating expenses	89		89
Short-term lease cost	Other operating expenses	1		4
Variable lease cost	Landing fees and airport rentals, and Other operating expenses	1,260		1,377
Finance lease cost:
Amortization of lease liabilities	Depreciation and amortization	113		116
Interest on lease liabilities	Interest expense	22		26
Total net finance lease cost		$	135	$	142

(a) Net of sublease income of $78 million and $97 million for the years ended December 31, 2020 and 2019.

Schedule of Cash Flow, Supplemental Disclosures

Supplemental cash flow information related to leases, included in the Consolidated Statement of Cash Flows, was as follows:

(in millions)	Year ended December 31, 2020		Year ended December 31, 2019
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows for operating leases	$	398	$	379
Operating cash flows for finance leases	22		26
Financing cash flows for finance leases	85		85
Right-of-use assets obtained in exchange for lease obligations:
Operating leases	915		230
Finance leases	—		1

Finance Lease Maturity

As of December 31, 2020, maturities of lease liabilities were as follows:

(in millions)	Operating leases		Finance leases
2021	$	371	$	102
2022	253		98
2023	219		94
2024	193		90
2025	156		74
Thereafter	1,156		156
Total lease payments	$	2,348	$	614
Less imputed interest	(480)		(72)
Total lease obligations	1,868		542
Less current obligations	(306)		(83)
Long-term lease obligations	$	1,562	$	459

Operating Lease Maturity

As of December 31, 2020, maturities of lease liabilities were as follows:

(in millions)	Operating leases		Finance leases
2021	$	371	$	102
2022	253		98
2023	219		94
2024	193		90
2025	156		74
Thereafter	1,156		156
Total lease payments	$	2,348	$	614
Less imputed interest	(480)		(72)
Total lease obligations	1,868		542
Less current obligations	(306)		(83)
Long-term lease obligations	$	1,562	$	459

Lessee Operating and Finance Leases Weighted Average Assumptions

The table below presents additional information related to the Company's leases:

Weighted average remaining lease term	December 31, 2020		December 31, 2019
Operating leases	10 years		9 years
Finance leases	7 years		8 years
Weighted average discount rate
Operating leases (a)	3.8	%	3.7	%
Finance leases	3.8	%	3.8	%

(a) Upon adoption of the New Lease Standard, the incremental borrowing rate used for existing leases was established as of January 1, 2019.