Condensed Consolidating Balance Sheets (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Assets:
Current assets	$ 780.3	$ 942.4
Investments	43.3	41.1
Investments in consolidated subsidiaries	0	0
Restricted funds	0	4.2
Property and equipment (including concession assets), net	6,909.4	6,356.3
Other assets	84.0	91.4
Total assets	7,817.0	7,435.4
Liabilities and equity:
Current liabilities	760.9	730.6
Long-term debt	1,846.1	1,856.9
Deferred income taxes	1,128.0	1,044.6
Other liabilities	128.9	126.7
Stockholders' equity	3,646.1	3,370.6
Noncontrolling interest	307.0	306.0
Total liabilities and equity	7,817.0	7,435.4
Parent [Member]
Assets:
Current assets	4.6	2.6
Investments	0	0
Investments in consolidated subsidiaries	2,495.9	2,154.6
Restricted funds		0
Property and equipment (including concession assets), net	0	0.1
Other assets	1.6	1.5
Total assets	2,502.1	2,158.8
Liabilities and equity:
Current liabilities	(1,164.4)	(1,216.5)
Long-term debt	0.2	0.2
Deferred income taxes	7.2	(11.7)
Other liabilities	3.4	6.6
Stockholders' equity	3,655.7	3,380.2
Noncontrolling interest	0	0
Total liabilities and equity	2,502.1	2,158.8
KCSR [Member]
Assets:
Current assets	231.3	403.0
Investments	3.9	9.6
Investments in consolidated subsidiaries	(3.2)	(2.1)
Restricted funds		0
Property and equipment (including concession assets), net	3,171.2	2,780.4
Other assets	46.0	50.9
Total assets	3,449.2	3,241.8
Liabilities and equity:
Current liabilities	1,639.0	1,580.6
Long-term debt	701.9	704.3
Deferred income taxes	759.0	719.8
Other liabilities	97.0	92.0
Stockholders' equity	252.3	145.1
Noncontrolling interest	0	0
Total liabilities and equity	3,449.2	3,241.8
Guarantor Subsidiaries [Member]
Assets:
Current assets	6.3	8.8
Investments	0	0
Investments in consolidated subsidiaries	466.0	461.8
Restricted funds		0
Property and equipment (including concession assets), net	193.8	198.6
Other assets	0	0
Total assets	666.1	669.2
Liabilities and equity:
Current liabilities	118.4	130.7
Long-term debt	0.2	0.2
Deferred income taxes	130.1	127.6
Other liabilities	0.7	0.7
Stockholders' equity	109.7	104.0
Noncontrolling interest	307.0	306.0
Total liabilities and equity	666.1	669.2
Non-Guarantor Subsidiaries [Member]
Assets:
Current assets	574.5	560.1
Investments	39.4	31.5
Investments in consolidated subsidiaries	0	0
Restricted funds		4.2
Property and equipment (including concession assets), net	3,544.4	3,377.2
Other assets	36.4	39.0
Total assets	4,194.7	4,012.0
Liabilities and equity:
Current liabilities	204.3	267.9
Long-term debt	1,143.8	1,152.2
Deferred income taxes	231.7	208.9
Other liabilities	27.8	27.5
Stockholders' equity	2,587.1	2,355.5
Noncontrolling interest	0	0
Total liabilities and equity	4,194.7	4,012.0
Consolidating Adjustments [Member]
Assets:
Current assets	(36.4)	(32.1)
Investments	0	0
Investments in consolidated subsidiaries	(2,958.7)	(2,614.3)
Restricted funds		0
Property and equipment (including concession assets), net	0	0
Other assets	0	0
Total assets	(2,995.1)	(2,646.4)
Liabilities and equity:
Current liabilities	(36.4)	(32.1)
Long-term debt	0	0
Deferred income taxes	0	0
Other liabilities	0	(0.1)
Stockholders' equity	(2,958.7)	(2,614.2)
Noncontrolling interest	0	0
Total liabilities and equity	$ (2,995.1)	$ (2,646.4)