Effective interest rate for the funds borrowed under the debt agreement considering the effect of cash flow hedge.

No definition available.

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- Definition

Weighted average fixed interest rate related to the group of interest rate derivatives.

+ References

No definition available.

+ Details

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- Definition

The net cash outflow or inflow from settlement of a financial contract that meets the hedge criteria as a cash flow hedge, classified as operating activities.

+ References

No definition available.

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- Definition

Term of future forecasted debt issuance.

+ References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Nominal or face amount used to calculate payment on derivative.

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- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

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Derivative Instruments Interest Rate Derivative Instruments (Details) $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	May 31, 2017 USD ($) Treasury_Lock_Agreements	Dec. 31, 2019 USD ($)	Dec. 31, 2020 USD ($) Treasury_Lock_Agreements	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Derivative [Line Items]
Term of future forecasted debt issuance			30 years
Long-term debt instrument, gross			$ 3,810.9
Cash paid for settlement of treasury lock agreements			0.0	$ 25.8	$ 0.0
Senior Notes [Member] \| 3.00% Senior Notes due May 15, 2023 [Member]
Derivative [Line Items]
Long-term debt instrument, gross			$ 444.7
Debt instrument, stated interest rate			3.00%
Debt instrument, maturity date			May 15, 2023
Senior Notes [Member] \| 3.85% Senior Notes due November 15, 2023 [Member]
Derivative [Line Items]
Long-term debt instrument, gross			$ 200.0
Debt instrument, stated interest rate			3.85%
Debt instrument, maturity date			Nov. 15, 2023
Senior Notes [Member] \| 2.35% Senior Notes due May 15, 2020 [Member]
Derivative [Line Items]
Long-term debt instrument, gross	$ 275.0
Debt instrument, stated interest rate	2.35%
Debt instrument, maturity date	May 15, 2020
Senior Notes [Member] \| 2.875% Senior Notes due November 15, 2029 [Member] \| KCS [Member]
Derivative [Line Items]
Debt instrument, stated interest rate		2.875%		2.875%
Debt instrument, maturity date		Nov. 15, 2029
Debt instrument, face amount		$ 425.0		$ 425.0
Debt instrument, interest rate effective percentage after effect of cash flow hedge		3.60%		3.60%
Treasury Lock Agreements [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member]
Derivative [Line Items]
Number of treasury lock agreements executed \| Treasury_Lock_Agreements	4		6
Aggregate notional value of treasury lock agreements	$ 275.0		$ 650.0
Weighted-average interest rate of treasury lock agreements	2.85%		1.58%
Cash paid for settlement of treasury lock agreements		$ 25.8