Condensed Consolidating Statements of Comprehensive Income (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
Condensed Statements of Comprehensive Income Captions [Line Items]
Revenues	$ 677.5	$ 621.6	$ 1,934.6	$ 1,753.7
Operating expenses	448.1	421.3	1,339.4	1,211.2
Operating income	229.4	200.3	595.2	542.5
Equity in net earnings (losses) of unconsolidated affiliates	5.0	4.8	16.6	13.8
Interest expense	(17.9)	(18.3)	(54.5)	(61.2)
Debt retirement costs	0	(2.4)	(6.6)	(113.8)
Foreign exchange loss	(12.5)	(1.4)	(4.1)	(10.1)
Other income (expense), net	(0.4)	(0.7)	(3.7)	(0.5)
Income before income taxes	203.6	182.3	542.9	370.7
Income tax expense	65.2	63.3	180.3	131.8
Net income	138.4	119.0	362.6	238.9
Less: Net income attributable to noncontrolling interest	0.3	0.6	1.0	1.3
Net income attributable to Kansas City Southern and subsidiaries	138.1	118.4	361.6	237.6
Other comprehensive income (loss)	(0.3)	0	(0.3)	0.3
Comprehensive income attributable to Kansas City Southern and subsidiaries	137.8	118.4	361.3	237.9
Parent [Member]
Condensed Statements of Comprehensive Income Captions [Line Items]
Revenues	0	0	0	0
Operating expenses	1.6	1.1	6.7	3.7
Operating income	(1.6)	(1.1)	(6.7)	(3.7)
Equity in net earnings (losses) of unconsolidated affiliates	131.0	114.8	346.5	222.7
Interest expense	(0.1)	(0.1)	(0.1)	(0.1)
Debt retirement costs	0	0	0	0
Foreign exchange loss	0	0	0	0
Other income (expense), net	12.4	11.0	37.9	33.4
Income before income taxes	141.7	124.6	377.6	252.3
Income tax expense	3.6	6.2	16.0	14.7
Net income	138.1	118.4	361.6	237.6
Less: Net income attributable to noncontrolling interest	0	0	0	0
Net income attributable to Kansas City Southern and subsidiaries	138.1	118.4	361.6	237.6
Other comprehensive income (loss)	(0.3)	0	(0.3)	0.3
Comprehensive income attributable to Kansas City Southern and subsidiaries	137.8	118.4	361.3	237.9
KCSR [Member]
Condensed Statements of Comprehensive Income Captions [Line Items]
Revenues	327.4	295.9	913.7	836.1
Operating expenses	228.5	212.3	674.7	617.8
Operating income	98.9	83.6	239.0	218.3
Equity in net earnings (losses) of unconsolidated affiliates	(0.1)	(0.2)	0.5	1.0
Interest expense	(20.6)	(17.8)	(62.9)	(49.4)
Debt retirement costs	0	0	(2.7)	(1.5)
Foreign exchange loss	0	0	0	(1.6)
Other income (expense), net	(0.3)	1.0	0.1	4.2
Income before income taxes	77.9	66.6	174.0	171.0
Income tax expense	29.8	25.7	66.7	63.9
Net income	48.1	40.9	107.3	107.1
Less: Net income attributable to noncontrolling interest	0	0	0	0
Net income attributable to Kansas City Southern and subsidiaries	48.1	40.9	107.3	107.1
Other comprehensive income (loss)	(0.1)	0	0	0.4
Comprehensive income attributable to Kansas City Southern and subsidiaries	48.0	40.9	107.3	107.5
Guarantor Subsidiaries [Member]
Condensed Statements of Comprehensive Income Captions [Line Items]
Revenues	12.7	10.7	36.4	30.9
Operating expenses	10.4	9.9	30.4	28.5
Operating income	2.3	0.8	6.0	2.4
Equity in net earnings (losses) of unconsolidated affiliates	1.2	1.8	3.3	4.0
Interest expense	0	0	0	0
Debt retirement costs	0	0	0	0
Foreign exchange loss	0	0	0	0
Other income (expense), net	0	0	0	(0.1)
Income before income taxes	3.5	2.6	9.3	6.3
Income tax expense	1.4	0.9	3.6	2.3
Net income	2.1	1.7	5.7	4.0
Less: Net income attributable to noncontrolling interest	0.3	0.6	1.0	1.3
Net income attributable to Kansas City Southern and subsidiaries	1.8	1.1	4.7	2.7
Other comprehensive income (loss)	0	0	0	0
Comprehensive income attributable to Kansas City Southern and subsidiaries	1.8	1.1	4.7	2.7
Non-Guarantor Subsidiaries [Member]
Condensed Statements of Comprehensive Income Captions [Line Items]
Revenues	348.2	325.1	1,015.5	916.6
Operating expenses	218.4	208.8	659.7	593.0
Operating income	129.8	116.3	355.8	323.6
Equity in net earnings (losses) of unconsolidated affiliates	4.4	4.3	14.9	11.2
Interest expense	(9.6)	(12.3)	(29.5)	(47.4)
Debt retirement costs	0	(2.4)	(3.9)	(112.3)
Foreign exchange loss	(12.5)	(1.4)	(4.1)	(8.5)
Other income (expense), net	(0.1)	(0.2)	(2.6)	(0.4)
Income before income taxes	112.0	104.3	330.6	166.2
Income tax expense	30.4	30.4	94.0	50.8
Net income	81.6	73.9	236.6	115.4
Less: Net income attributable to noncontrolling interest	0	0	0	0
Net income attributable to Kansas City Southern and subsidiaries	81.6	73.9	236.6	115.4
Other comprehensive income (loss)	(0.5)	0	(0.4)	0
Comprehensive income attributable to Kansas City Southern and subsidiaries	81.1	73.9	236.2	115.4
Consolidating Adjustments [Member]
Condensed Statements of Comprehensive Income Captions [Line Items]
Revenues	(10.8)	(10.1)	(31.0)	(29.9)
Operating expenses	(10.8)	(10.8)	(32.1)	(31.8)
Operating income	0	0.7	1.1	1.9
Equity in net earnings (losses) of unconsolidated affiliates	(131.5)	(115.9)	(348.6)	(225.1)
Interest expense	12.4	11.9	38.0	35.7
Debt retirement costs	0	0	0	0
Foreign exchange loss	0	0	0	0
Other income (expense), net	(12.4)	(12.5)	(39.1)	(37.6)
Income before income taxes	(131.5)	(115.8)	(348.6)	(225.1)
Income tax expense	0	0.1	0	0.1
Net income	(131.5)	(115.9)	(348.6)	(225.2)
Less: Net income attributable to noncontrolling interest	0	0	0	0
Net income attributable to Kansas City Southern and subsidiaries	(131.5)	(115.9)	(348.6)	(225.2)
Other comprehensive income (loss)	0.6	0	0.4	(0.4)
Comprehensive income attributable to Kansas City Southern and subsidiaries	$ (130.9)	$ (115.9)	$ (348.2)	$ (225.6)