FINANCIAL INFORMATION BY BUSINESS SEGMENTS (Tables)

12 Months Ended

Dec. 31, 2017

Notes To Financial Statements [Abstract]

Results of Reportable Segment

The results of our reportable segment are as follows (in millions):

	North America		All Other  (1)			Total
Year Ended December 31, 2017
Operating revenue	$	1,721	$	31		$	1,752
Depreciation and amortization expense	$	209	$	6		$	215
Impairment charges	$	2	$	—		$	2
Operating income	$	95	$	6		$	101
Equity in net income from unconsolidated investments	$	1	$	—		$	1
As of December 31, 2017
Total assets	$	3,753	$	688		$	4,441
Capital additions	$	155	$	122		$	277
Year Ended December 31, 2016
Operating revenue	$	1,692	$	7		$	1,699
Depreciation and amortization expense	$	207	$	—		$	207
Impairment charges	$	20	$	—		$	20
Operating income (loss)	$	116	$	(7	)	$	109
Equity in net income from unconsolidated investments	$	1	$	3		$	4
As of December 31, 2016
Total assets	$	3,794	$	490		$	4,284
Capital additions	$	188	$	171		$	359
Year Ended December 31, 2015
Operating revenue	$	1,607	$	38		$	1,645
Depreciation and amortization expense	$	197	$	1		$	198
Impairment charges	$	43	$	—		$	43
Operating income	$	108	$	1		$	109
Equity in net income from unconsolidated investments	$	—	$	13		$	13

(1) All other includes the financial results of our international assets.

Schedule Of Revenue And Total Assets By Geographic Location Table [Text Block]

A summary of operating revenue and total assets by geographic area is as follows (in millions):

	United States		Other		Total
Operating Revenue:
Year Ended December 31, 2017	$	1,705	$	47	$	1,752
Year Ended December 31, 2016	$	1,677	$	22	$	1,699
Year Ended December 31, 2015	$	1,589	$	56	$	1,645

	United States		Assets Held for Sale		Other		Total
Total Assets:
Year Ended December 31, 2017	$	3,727	$	653	$	61	$	4,441
Year Ended December 31, 2016	$	3,763	$	—	$	521	$	4,284
Year Ended December 31, 2015	$	3,847	$	97	$	290	$	4,234