Amount Payable to Redeem the Notes, Percent of the Principal Amount

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- Definition

Debt Instrument Maturity Year

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Discount Rate used to Compute the Remaining Scheduled Payments of Principal and Interest

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- Definition

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

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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.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average interest rate of debt outstanding.

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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The fair value of notes issued in noncash investing and financing activities.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Credit and Other Debt Agreements - Note Purchase Agreements - Additional Information (Detail) - USD ($) $ in Millions				12 Months Ended
	May 05, 2021	Feb. 10, 2021	Jan. 30, 2020	Dec. 31, 2021	Dec. 31, 2020
Fixed Rate of 3.75% Senior Notes Due in 2027 [Member]
Debt Instrument [Line Items]
Notes issued and sold				$ 30.0
Debt instrument, interest rate				3.75%
Debt instrument, due date				2027
Fixed Rate of 3.99% Senior Notes Due in 2030 [Member]
Debt Instrument [Line Items]
Notes issued and sold				$ 341.0
Debt instrument, interest rate				3.99%
Debt instrument, due date				2030
Fixed Rate of 4.09% Senior Notes Due in 2032 [Member]
Debt Instrument [Line Items]
Notes issued and sold				$ 69.0
Debt instrument, interest rate				4.09%
Debt instrument, due date				2032
Fixed Rate of 4.24% Senior Notes Due in 2035 [Member]
Debt Instrument [Line Items]
Notes issued and sold				$ 79.0
Debt instrument, interest rate				4.24%
Debt instrument, due date				2035
Fixed Rate of 4.49% Senior Notes Due in 2040 [Member]
Debt Instrument [Line Items]
Notes issued and sold				$ 56.0
Debt instrument, interest rate				4.49%
Debt instrument, due date				2040
Fixed Rate of 5.18%, Balloon Due February 10, 2021 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate					5.18%
Note Purchase Agreements [Member]
Debt Instrument [Line Items]
Realized a cash gain (loss) on hedging transaction	$ (17.2)	$ (22.9)	$ (8.9)
Derivative instrument, term	10 years	10 years	10 years
Amount payable to redeem the notes, percent of the principal amount				100.00%
Discount rate used to compute the remaining scheduled payments of principal and interest				U.S. Treasury yield plus 0.5
Note Purchase Agreements [Member] \| Fixed Rate of 5.18%, Balloon Due February 10, 2021 [Member]
Debt Instrument [Line Items]
Repayments of debt		$ 75.0
Note Purchase Agreements [Member] \| Private Placement [Member] \| Unsecured Notes [Member]
Debt Instrument [Line Items]
Notes issued and sold	$ 75.0	$ 100.0	$ 575.0
Weighted average maturity of notes	15 years	15 years	11 years 8 months 12 days
Weighted average interest rate of notes	3.98%	3.97%	4.23%
Debt instrument, interest rate	2.46%	2.44%
Debt instrument, due date	2036	2036