Equity (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 3,739.3	$ 3,487.1	$ 3,676.6	$ 3,400.7
Net income	130.2	15.7	224.2	119.9
Other comprehensive income (loss)	0	(0.3)	0	0.3
Dividends on common stock	(30.9)	(23.8)	(61.8)	(47.4)
Options exercised and stock subscribed, net of shares withheld for employee taxes	0.2	0.5	(4.0)	(1.7)
Excess tax benefit from share-based compensation	0.1	0.4	2.5	3.3
Share-based compensation	2.9	3.7	4.4	8.3
Ending balance	3,841.8	3,483.3	3,841.8	3,483.3
$25 Par Preferred Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends on $25 par preferred stock	0	0	(0.1)	(0.1)
Kansas City Southern Stockholders' Equity [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	3,433.0	3,182.6	3,370.6	3,096.6
Net income	129.8	15.4	223.5	119.2
Other comprehensive income (loss)	0	(0.3)	0	0.3
Dividends on common stock	(30.9)	(23.8)	(61.8)	(47.4)
Options exercised and stock subscribed, net of shares withheld for employee taxes	0.2	0.5	(4.0)	(1.7)
Excess tax benefit from share-based compensation	0.1	0.4	2.5	3.3
Share-based compensation	2.9	3.7	4.4	8.3
Ending balance	3,535.1	3,178.5	3,535.1	3,178.5
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	0	(0.1)	(0.1)
Noncontrolling Interest [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	306.3	304.5	306.0	304.1
Net income	0.4	0.3	0.7	0.7
Ending balance	$ 306.7	$ 304.8	$ 306.7	$ 304.8