Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Reconciliation of cash, cash equivalents, and restricted cash

The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the Consolidated Balance Sheets ("balance sheets") that sum to the total of the same such amounts shown within the Consolidated Statements of Cash Flows ("cash flows statement").

Reconciliation of cash, cash equivalents and restricted cash
	December 31,
(in millions)	2021		2020		2019
Current assets:
Cash and cash equivalents	$	7,933	$	8,307	$	2,882
Restricted cash included in prepaid expenses and other	163		192		212
Noncurrent assets:
Cash restricted for airport construction	473		1,556		636
Total cash, cash equivalents and restricted cash	$	8,569	$	10,055	$	3,730

Summary of property and equipment by classification

The following table summarizes our property and equipment:

Property and equipment by classification
		December 31,
(in millions, except for estimated useful life)	Estimated Useful Life	2021		2020
Flight equipment	20-34 years	$	33,368	$	31,572
Ground property and equipment	3-40 years	7,758		6,387
Information technology-related assets	3-15 years	3,389		3,403
Flight and ground equipment under finance leases	Shorter of lease term or estimated useful life	2,052		1,795
Advance payments for equipment		853		883
Less: accumulated depreciation and amortization(1)		(18,671)		(17,511)
Total property and equipment, net		$	28,749	$	26,529

(1)Includes accumulated amortization for flight and ground equipment under finance leases in the amount of $456 million and $793 million at December 31, 2021 and 2020, respectively.