PROPERTY AND EQUIPMENT

12 Months Ended

Dec. 31, 2019

Property Plant And Equipment [Abstract]

PROPERTY AND EQUIPMENT

NOTE 7: PROPERTY AND EQUIPMENT

Property and equipment includes land, buildings and improvements, machinery and equipment, roads and other items.

Carrying Value of Property and Equipment and Estimated Service Lives

DOLLAR AMOUNTS IN MILLIONS
	RANGE OF LIVES	DECEMBER 31, 2019			DECEMBER 31, 2018
Property and equipment, at cost:
Land	N/A	$	87		$	87
Buildings and improvements	15-40		999			942
Machinery and equipment	5-25		3,425			3,240
Roads	10-35		742			785
Other	3-10		193			179
Total cost			5,446			5,233
Accumulated depreciation and amortization			(3,477	)		(3,376	)
Property and equipment, net		$	1,969		$	1,857

SERVICE LIVES AND DEPRECIATION

In general, additions are classified into components, each with its own estimated useful life as determined at the time of purchase.

Depreciation and amortization expense for property and equipment was:

• $240 million in 2019,

• $197 million in 2018 and

• $206 million in 2017.