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Estimated interest payments year three.

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

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Debt - Additional Information (Details) - USD ($) $ in Millions						12 Months Ended
	Aug. 11, 2025	Nov. 30, 2023	Sep. 21, 2021	Nov. 21, 2019	Dec. 13, 2017	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Jul. 31, 2025	Sep. 15, 2024
Debt Instrument [Line Items]
Less unamortized debt issuance costs						$ 25.2	$ 18.0
Stated interest rate						4.28%	3.69%
Credit Agreement						$ 3,992.5	$ 2,492.2
Letters of Credit Outstanding Amount						27.5
Unused borrowing capacity						572.5
Debt instrument, redemption amount included premiums, accrued and unpaid interest										$ 407.3
Annual principal maturities for debt
2026						0.0
2027						500.0
2028						500.0
2029						500.0
2030 and thereafter							2,500.0
Interest payments						100.6	107.7	$ 84.8
Estimated interest payments for 2026						118.4
Estimated interest payments for 2027						92.4
Estimated interest payments for 2028						75.4
Estimated interest payments for 2029						75.4
Estimated interest payments for 2030 and thereafter						1,040.9
Amortization of financing costs						4.9	$ 1.8	1.6
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit Agreement						$ 0.0
Senior Notes
Debt Instrument [Line Items]
Stated interest rate						0.00%	0.00%
Credit Agreement						$ 0.0	$ 0.0
Unsecured Term Loan Facility
Debt Instrument [Line Items]
Credit Agreement									$ 500.0
Unsecured Revolving Credit Facility
Debt Instrument [Line Items]
Credit Agreement									600.0
Farm Credit Agreement
Debt Instrument [Line Items]
Credit Agreement									$ 500.0
Old Credit Agreement [Member]
Debt Instrument [Line Items]
Credit Agreement						0.0
3 Year Term Loan, due September 2028 \| Senior Notes
Debt Instrument [Line Items]
Debt, face amount	$ 500.0					$ 500.0
Stated interest rate	5.20%					4.84%	0.00%
Credit Agreement						$ 500.0	$ 0.0
September 15, 2024	Aug. 15, 2035
7 Year Farm Credit Loan, due September 2032 \| Senior Notes
Debt Instrument [Line Items]
Debt, face amount						$ 500.0
Stated interest rate						5.69%	0.00%
Credit Agreement						$ 500.0	$ 0.0
3.65% Senior Notes, Due September 2024
Debt Instrument [Line Items]
Stated interest rate										3.65%
Debt instrument, redemption amount included premiums, accrued and unpaid interest										$ 407.3
3.65% Senior Notes, Due September 2024 \| Senior Notes
Debt Instrument [Line Items]
Stated interest rate										3.65%
3.40% Senior Notes, Due December 2027 \| Senior Notes
Debt Instrument [Line Items]
Debt, face amount					$ 500.0
Stated interest rate					3.40%	3.40%	3.40%
Credit Agreement						$ 499.6	$ 499.4
September 15, 2024					Dec. 15, 2027	Dec. 15, 2027	Dec. 15, 2027
3.00% Senior Notes, Due December 2029 \| Senior Notes
Debt Instrument [Line Items]
Debt, face amount				$ 500.0
Stated interest rate				3.00%		3.00%	3.00%
Credit Agreement						$ 499.7	$ 499.7
September 15, 2024				Dec. 15, 2029		Dec. 15, 2027	Dec. 15, 2027
5.70% Senior Notes, Due December 2033
Debt Instrument [Line Items]
Stated interest rate										5.70%
5.70% Senior Notes, Due December 2033 \| Senior Notes
Debt Instrument [Line Items]
Debt, face amount		$ 400.0								$ 400.0
Stated interest rate		5.70%				5.70%	5.70%			5.70%
Credit Agreement						$ 399.7	$ 399.7
September 15, 2024		Dec. 01, 2033				Dec. 15, 2029	Dec. 15, 2029
5.20% Senior Notes, Due August 2035 \| Senior Notes
Debt Instrument [Line Items]
Debt, face amount	$ 500.0
Less unamortized debt issuance costs	$ 4.9
Stated interest rate	5.20%					5.20%	0.00%
Credit Agreement						$ 499.9	$ 0.0
September 15, 2024						Sep. 15, 2024	Sep. 15, 2024
4.05% Senior Notes, Due December 2049 \| Senior Notes
Debt Instrument [Line Items]
Debt, face amount				$ 400.0
Stated interest rate				4.05%		4.05%	4.05%
Credit Agreement						$ 396.9	$ 396.8
September 15, 2024				Dec. 15, 2049		Dec. 15, 2049	Dec. 15, 2049
3.05% Senior Notes, Due October 2051 \| Senior Notes
Debt Instrument [Line Items]
Debt, face amount			$ 700.0
Stated interest rate			3.05%			3.05%	3.05%
Credit Agreement						$ 696.7	$ 696.6
September 15, 2024			Oct. 01, 2051			Oct. 15, 2051	Oct. 15, 2051
Fixed-Rate Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Book value of fixed rate debt						$ 2,992.5
Long-term debt (fixed-rate debt), fair value						2,679.7
Variable Rate Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Book value of fixed rate debt						1,000.0
Bonds [Member]
Annual principal maturities for debt
Amortization of financing costs						$ 0.4	$ 0.5	$ 0.5