Operating Segments and Related Disclosures (Tables)

12 Months Ended

Dec. 31, 2016

Segment Reporting [Abstract]

Operating revenues by geographic region

Operating revenues by geographic region as defined by the Department of Transportation (DOT) area are summarized below:

	2016		2015		2014
	(in millions)
DOT—Domestic	$	2,136.2	$	1,940.2	$	1,728.8
DOT—Latin America	185.8		201.3		202.8
Total	$	2,322.0	$	2,141.5	$	1,931.6