Debt (Tables)

12 Months Ended

Dec. 31, 2018

Debt Disclosure [Abstract]

Summary of Long-Term Debt

(In millions)	At December 31,
	2018			2017
Secured
Notes payable, fixed interest rates of 0.0% to 9.52% (weighted average rate of 4.18% as of December 31, 2018), payable through 2030	$	8,811		$	8,661
Notes payable, floating interest rates of the London interbank offered rate ("LIBOR") plus 1.05% to 1.75%, payable through 2030	2,051			1,880
Term loan, LIBOR plus 1.75%, or alternative rate based on certain market rates plus 0.75%, due 2024	1,474			1,489
Unsecured
6.375% Senior Notes due 2018 (a)	—			300
6% Senior Notes due 2020 (a)	300			300
4.25% Senior Notes due 2022 (a)	400			400
5% Senior Notes due 2024 (a)	300			300
Other	300			101
	13,636			13,431
Less: unamortized debt discount, premiums and debt issuance costs	(191		)	(163		)
Less: current portion of long-term debt	(1,230		)	(1,565		)
Long-term debt, net	$	12,215		$	11,703

(a) UAL is the issuer of this debt. United is a guarantor.

Contractual Principal Payments under Outstanding Long-Term Debt Agreements

The table below presents the Company's contractual principal payments (not including debt discount or debt issuance costs) at December 31, 2018 under then-outstanding long-term debt agreements in each of the next five calendar years (in millions):

2019	$	1,230
2020	1,310
2021	1,300
2022	1,653
2023	703
After 2023	7,440
	$	13,636

Details of Pass Through Trusts

Certain details of the pass-through trusts with proceeds received from issuance of debt in 2018 are as follows (in millions, except stated interest rate):

EETC Date	Class	Principal		Final expected distribution date	Stated interest rate		Total debt recorded as of December 31, 2018		Proceeds received from issuance of debt during 2018		Remaining proceeds from issuance of debt to be received in future periods
February 2019	AA	$	717	August 2031	4.15	%	$	—	$	—	$	717
February 2019	A	296		August 2031	4.55	%	—		—		296
May 2018	B	226		March 2026	4.60	%	226		226		—
February 2018	AA	677		March 2030	3.50	%	677		677		—
February 2018	A	258		March 2030	3.70	%	258		258		—
		$	2,174				$	1,161	$	1,161	$	1,013

Summary of Collateral Covenants and Cross Default Provisions

The collateral, covenants and cross default provisions of the Company's principal debt instruments that contain such provisions are summarized in the table below:

Debt Instrument	Collateral, Covenants and Cross Default Provisions
Various equipment notes and other notes payable	Secured by certain aircraft. The indentures contain events of default that are customary for aircraft financing, including in certain cases cross default to other related aircraft.
Credit Agreement	Secured by certain of United's international route authorities, specified take-off and landing slots at certain airports and certain other assets. The Credit Agreement requires the Company to maintain at least $2.0 billion of unrestricted liquidity at all times, which includes unrestricted cash, short-term investments and any undrawn amounts under any revolving credit facility, and to maintain a minimum ratio of appraised value of collateral to the outstanding obligations under the Credit Agreement of 1.6 to 1.0 at all times. The Credit Agreement contains covenants that, among other things, restrict the ability of UAL and its restricted subsidiaries (as defined in the Credit Agreement) to incur additional indebtedness and to pay dividends on or repurchase stock, although, as of December 31, 2018, the Company had ample ability under these restrictions to repurchase stock under the Company's share repurchase program. The Credit Agreement contains events of default customary for this type of financing, including a cross default and cross acceleration provision to certain other material indebtedness of the Company.
6% Senior Notes due 2020 4.25% Senior Notes due 2022 5% Senior Notes due 2024	The indentures for these notes contain covenants that, among other things, restrict the ability of the Company and its restricted subsidiaries (as defined in the indentures) to incur additional indebtedness and pay dividends on or repurchase stock, although the Company currently has ample ability under these restrictions to repurchase stock under the Company's share repurchase program.