Commitments, Contingencies and Off-Balance Sheet Arrangements - Contractual Obligations (Detail) $ in Millions	Mar. 31, 2024 USD ($)
Senior Notes [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, Thereafter	$ 4,550.0
Contractual Obligations, Payments Due by Period, Total	4,550.0
Note Purchase Agreements [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2025	200.0
Contractual Obligations, Payments Due by Period, 2026	640.0
Contractual Obligations, Payments Due by Period, 2027	478.0
Contractual Obligations, Payments Due by Period, 2028	200.0
Contractual Obligations, Payments Due by Period, Thereafter	2,005.0
Contractual Obligations, Payments Due by Period, Total	3,523.0
Credit Agreement [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2024	108.2
Contractual Obligations, Payments Due by Period, Total	108.2
Premium Financing Debt Facility [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2024	184.3
Contractual Obligations, Payments Due by Period, Total	184.3
Interest On Debt [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2024	240.4
Contractual Obligations, Payments Due by Period, 2025	374.0
Contractual Obligations, Payments Due by Period, 2026	355.0
Contractual Obligations, Payments Due by Period, 2027	336.7
Contractual Obligations, Payments Due by Period, 2028	317.2
Contractual Obligations, Payments Due by Period, Thereafter	4,285.8
Contractual Obligations, Payments Due by Period, Total	5,909.1
Total Debt Obligations [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2024	532.9
Contractual Obligations, Payments Due by Period, 2025	574.0
Contractual Obligations, Payments Due by Period, 2026	995.0
Contractual Obligations, Payments Due by Period, 2027	814.7
Contractual Obligations, Payments Due by Period, 2028	517.2
Contractual Obligations, Payments Due by Period, Thereafter	10,840.8
Contractual Obligations, Payments Due by Period, Total	14,274.6
Operating Lease Obligations [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2024	81.0
Contractual Obligations, Payments Due by Period, 2025	103.8
Contractual Obligations, Payments Due by Period, 2026	86.3
Contractual Obligations, Payments Due by Period, 2027	69.1
Contractual Obligations, Payments Due by Period, 2028	52.4
Contractual Obligations, Payments Due by Period, Thereafter	81.9
Contractual Obligations, Payments Due by Period, Total	474.5
Less Sublease Arrangements [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Receivable by Period, 2024	(1.7)
Contractual Obligations, Payments Receivable by Period, 2025	(1.8)
Contractual Obligations, Payments Receivable by Period, 2026	(1.6)
Contractual Obligations, Payments Receivable by Period, 2027	(1.6)
Contractual Obligations, Payments Receivable by Period, 2028	(1.1)
Contractual Obligations, Payments Receivable by Period, Thereafter	(0.8)
Contractual Obligations, Payments Receivable by Period, Total	(8.6)
Outstanding Purchase Obligations [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2024	103.5
Contractual Obligations, Payments Due by Period, 2025	68.1
Contractual Obligations, Payments Due by Period, 2026	28.2
Contractual Obligations, Payments Due by Period, 2027	21.6
Contractual Obligations, Payments Due by Period, 2028	15.1
Contractual Obligations, Payments Due by Period, Thereafter	47.1
Contractual Obligations, Payments Due by Period, Total	283.6
Total Contractual Obligations [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2024	715.7
Contractual Obligations, Payments Due by Period, 2025	744.1
Contractual Obligations, Payments Due by Period, 2026	1,107.9
Contractual Obligations, Payments Due by Period, 2027	903.8
Contractual Obligations, Payments Due by Period, 2028	583.6
Contractual Obligations, Payments Due by Period, Thereafter	10,969.0
Contractual Obligations, Payments Due by Period, Total	$ 15,024.1

Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]

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Recorded unconditional purchase obligation receivable.

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Recorded unconditional purchase obligation receivable after fifth year.

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Recorded unconditional purchase obligation receivable in fifth year.

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Recorded unconditional purchase obligation receivable in fourth year.

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Recorded unconditional purchase obligation receivable in second year.

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Recorded unconditional purchase obligation receivable in third year.

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Recorded unconditional purchase obligation receivable within one year.

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- Definition

Amount of the recorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 440
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482648/440-10-50-6

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- Definition

Amount of recorded unconditional purchase obligation maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 440
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482648/440-10-50-6

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Amount of recorded unconditional purchase obligation to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of recorded unconditional purchase obligation to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of recorded unconditional purchase obligation to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of recorded unconditional purchase obligation to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of recorded unconditional purchase obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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