XML 59 R43.htm IDEA: XBRL DOCUMENT v3.8.0.1
Schedule of Commitments to Purchase Aircrafts (Detail) - United Airlines, Inc. - Capital Addition Purchase Commitments
Mar. 31, 2018
Aircraft
[1]
Airbus A350 Aircraft  
Long-term Purchase Commitment [Line Items]  
Number of new aircraft committed to purchase 45
Boeing 737 MAX Aircraft  
Long-term Purchase Commitment [Line Items]  
Number of new aircraft committed to purchase 161
Boeing 777-300ER Aircraft  
Long-term Purchase Commitment [Line Items]  
Number of new aircraft committed to purchase 2
Boeing 787 Aircraft  
Long-term Purchase Commitment [Line Items]  
Number of new aircraft committed to purchase 14
[1] United also has options and purchase rights for additional aircraft.