Commitments, Contingencies and Off-Balance Sheet Arrangements - Contractual Obligations (Detail) $ in Millions	Jun. 30, 2021 USD ($)
Senior Notes [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, Thereafter	$ 1,500.0
Contractual Obligations, Payments Due by Period, Total	1,500.0
Note Purchase Agreements [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2022	200.0
Contractual Obligations, Payments Due by Period, 2023	250.0
Contractual Obligations, Payments Due by Period, 2024	475.0
Contractual Obligations, Payments Due by Period, 2025	200.0
Contractual Obligations, Payments Due by Period, Thereafter	3,323.0
Contractual Obligations, Payments Due by Period, Total	4,448.0
Premium Financing Debt Facility [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2021	166.1
Contractual Obligations, Payments Due by Period, Total	166.1
Interest On Debt [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2021	119.1
Contractual Obligations, Payments Due by Period, 2022	234.0
Contractual Obligations, Payments Due by Period, 2023	224.9
Contractual Obligations, Payments Due by Period, 2024	208.3
Contractual Obligations, Payments Due by Period, 2025	193.6
Contractual Obligations, Payments Due by Period, Thereafter	1,496.3
Contractual Obligations, Payments Due by Period, Total	2,476.2
Total Debt Obligations [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2021	285.2
Contractual Obligations, Payments Due by Period, 2022	434.0
Contractual Obligations, Payments Due by Period, 2023	474.9
Contractual Obligations, Payments Due by Period, 2024	683.3
Contractual Obligations, Payments Due by Period, 2025	393.6
Contractual Obligations, Payments Due by Period, Thereafter	6,319.3
Contractual Obligations, Payments Due by Period, Total	8,590.3
Operating Lease Obligations [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2021	52.9
Contractual Obligations, Payments Due by Period, 2022	101.8
Contractual Obligations, Payments Due by Period, 2023	81.8
Contractual Obligations, Payments Due by Period, 2024	59.7
Contractual Obligations, Payments Due by Period, 2025	45.3
Contractual Obligations, Payments Due by Period, Thereafter	87.6
Contractual Obligations, Payments Due by Period, Total	429.1
Less Sublease Arrangements [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Receivable by Period, 2021	(0.1)
Contractual Obligations, Payments Receivable by Period, 2022	(0.3)
Contractual Obligations, Payments Receivable by Period, 2023	(0.3)
Contractual Obligations, Payments Receivable by Period, 2024	(0.3)
Contractual Obligations, Payments Receivable by Period, 2025	(0.2)
Contractual Obligations, Payments Receivable by Period, Thereafter	(0.5)
Contractual Obligations, Payments Receivable by Period, Total	(1.7)
Outstanding Purchase Obligations [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2021	57.0
Contractual Obligations, Payments Due by Period, 2022	60.1
Contractual Obligations, Payments Due by Period, 2023	40.0
Contractual Obligations, Payments Due by Period, 2024	29.4
Contractual Obligations, Payments Due by Period, 2025	21.7
Contractual Obligations, Payments Due by Period, Thereafter	33.0
Contractual Obligations, Payments Due by Period, Total	241.2
Total Contractual Obligations [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2021	395.0
Contractual Obligations, Payments Due by Period, 2022	595.6
Contractual Obligations, Payments Due by Period, 2023	596.4
Contractual Obligations, Payments Due by Period, 2024	772.1
Contractual Obligations, Payments Due by Period, 2025	460.4
Contractual Obligations, Payments Due by Period, Thereafter	6,439.4
Contractual Obligations, Payments Due by Period, Total	$ 9,258.9

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 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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- 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 http://asc.fasb.org/extlink&oid=121559207&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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- Definition

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

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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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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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