Operating Segments and Related Disclosures (Tables)

12 Months Ended

Dec. 31, 2015

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:

	2015		2014		2013
	(in millions)
DOT—Domestic	$	1,940.2	$	1,728.8	$	1,467.5
DOT—Latin America	201.3		202.8		186.9
Total	$	2,141.5	$	1,931.6	$	1,654.4