Equity (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 3,841.8	$ 3,483.3	$ 3,676.6	$ 3,400.7
Net income	138.4	119.0	362.6	238.9
Other comprehensive income (loss)	(0.3)	0	(0.3)	0.3
Dividends on common stock	(30.9)	(23.6)	(92.7)	(71.0)
Options exercised and stock subscribed, net of shares withheld for employee taxes	1.9	0.7	(2.1)	(1.0)
Excess tax benefit from share-based compensation	0.5	0.4	3.0	3.7
Share-based compensation	1.8	3.0	6.2	11.3
Ending balance	3,953.1	3,582.7	3,953.1	3,582.7
$25 Par Preferred Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends on $25 par preferred stock	(0.1)	(0.1)	(0.2)	(0.2)
Kansas City Southern Stockholders' Equity [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	3,535.1	3,178.5	3,370.6	3,096.6
Net income	138.1	118.4	361.6	237.6
Other comprehensive income (loss)	(0.3)	0	(0.3)	0.3
Dividends on common stock	(30.9)	(23.6)	(92.7)	(71.0)
Options exercised and stock subscribed, net of shares withheld for employee taxes	1.9	0.7	(2.1)	(1.0)
Excess tax benefit from share-based compensation	0.5	0.4	3.0	3.7
Share-based compensation	1.8	3.0	6.2	11.3
Ending balance	3,646.1	3,277.3	3,646.1	3,277.3
Kansas City Southern Stockholders' Equity [Member] | $25 Par Preferred Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends on $25 par preferred stock	(0.1)	(0.1)	(0.2)	(0.2)
Noncontrolling Interest [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	306.7	304.8	306.0	304.1
Net income	0.3	0.6	1.0	1.3
Ending balance	$ 307.0	$ 305.4	$ 307.0	$ 305.4