Commitments, Contingencies and Off-Balance Sheet Arrangements - Contractual Obligations (Detail) $ in Millions	Mar. 31, 2023 USD ($)
Senior Notes [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, Thereafter	$ 2,550.0
Contractual Obligations, Payments Due by Period, Total	2,550.0
Note Purchase Agreements [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2023	200.0
Contractual Obligations, Payments Due by Period, 2024	475.0
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, Thereafter	2,205.0
Contractual Obligations, Payments Due by Period, Total	4,198.0
Credit Agreement [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, Total	0.0
Premium Financing Debt Facility [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2023	159.8
Contractual Obligations, Payments Due by Period, Total	159.8
Interest On Debt [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2023	198.3
Contractual Obligations, Payments Due by Period, 2024	265.2
Contractual Obligations, Payments Due by Period, 2025	251.4
Contractual Obligations, Payments Due by Period, 2026	232.6
Contractual Obligations, Payments Due by Period, 2027	214.1
Contractual Obligations, Payments Due by Period, Thereafter	2,393.8
Contractual Obligations, Payments Due by Period, Total	3,555.4
Total Debt Obligations [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2023	558.1
Contractual Obligations, Payments Due by Period, 2024	740.2
Contractual Obligations, Payments Due by Period, 2025	451.4
Contractual Obligations, Payments Due by Period, 2026	872.6
Contractual Obligations, Payments Due by Period, 2027	692.1
Contractual Obligations, Payments Due by Period, Thereafter	7,148.8
Contractual Obligations, Payments Due by Period, Total	10,463.2
Operating Lease Obligations [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2023	74.4
Contractual Obligations, Payments Due by Period, 2024	91.3
Contractual Obligations, Payments Due by Period, 2025	74.0
Contractual Obligations, Payments Due by Period, 2026	58.9
Contractual Obligations, Payments Due by Period, 2027	45.6
Contractual Obligations, Payments Due by Period, Thereafter	93.1
Contractual Obligations, Payments Due by Period, Total	437.3
Less Sublease Arrangements [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Receivable by Period, 2023	(0.7)
Contractual Obligations, Payments Receivable by Period, 2024	(0.6)
Contractual Obligations, Payments Receivable by Period, 2025	(0.3)
Contractual Obligations, Payments Receivable by Period, 2026	(0.3)
Contractual Obligations, Payments Receivable by Period, 2027	(0.2)
Contractual Obligations, Payments Receivable by Period, Thereafter	(0.1)
Contractual Obligations, Payments Receivable by Period, Total	(2.2)
Outstanding Purchase Obligations [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2023	99.7
Contractual Obligations, Payments Due by Period, 2024	95.3
Contractual Obligations, Payments Due by Period, 2025	47.9
Contractual Obligations, Payments Due by Period, 2026	19.0
Contractual Obligations, Payments Due by Period, 2027	15.7
Contractual Obligations, Payments Due by Period, Thereafter	49.5
Contractual Obligations, Payments Due by Period, Total	327.1
Total Contractual Obligations [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2023	731.5
Contractual Obligations, Payments Due by Period, 2024	926.2
Contractual Obligations, Payments Due by Period, 2025	573.0
Contractual Obligations, Payments Due by Period, 2026	950.2
Contractual Obligations, Payments Due by Period, 2027	753.2
Contractual Obligations, Payments Due by Period, Thereafter	7,291.3
Contractual Obligations, Payments Due by Period, Total	$ 11,225.4

Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]

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Recorded unconditional purchase obligation due after fourth year.

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Recorded unconditional purchase obligation receivable.

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Recorded unconditional purchase obligation receivable after fourth year.

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Recorded unconditional purchase obligation receivable in fourth year.

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Recorded unconditional purchase obligation receivable in remainder of fiscal year.

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- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 6
-URI https://asc.fasb.org/extlink&oid=123406679&loc=d3e25383-109308

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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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Amount of recorded unconditional purchase obligation to be paid in remainder of current fiscal year.

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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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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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