GENERAL AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Property, Plant and Equipment [Table Text Block]

Property and equipment are recorded at cost and depreciated using the straight-line method over their estimated useful lives less an estimated salvage value, which are as follows:

	Estimated Useful Life	Estimated Salvage Value
Aircraft and other flight equipment:
Boeing 737 and E175 aircraft	20-25 years	10%
Bombardier Q400 aircraft	15 years	5%
Buildings	25 - 40 years	10%
Minor building and land improvements	10 years	—%
Capitalized leases and leasehold improvements	Generally shorter of lease term or estimated useful life	—%
Computer hardware and software	3-10 years	—%
Other furniture and equipment	5-10 years	—%