Commitments, Contingencies and Off-Balance Sheet Arrangements - Contractual Obligations (Detail) $ in Millions	Mar. 31, 2017 USD ($)
Note Purchase Agreements [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2017	$ 300.0
Contractual Obligations, Payments Due by Period, 2018	100.0
Contractual Obligations, Payments Due by Period, 2019	100.0
Contractual Obligations, Payments Due by Period, 2020	100.0
Contractual Obligations, Payments Due by Period, 2021	75.0
Contractual Obligations, Payments Due by Period, Thereafter	1,775.0
Contractual Obligations, Payments Due by Period, Total	2,450.0
Multi Currency Credit Agreement [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2017	395.0
Contractual Obligations, Payments Due by Period, Total	395.0
Premium Financing Debt Facility [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2017	104.4
Contractual Obligations, Payments Due by Period, Total	104.4
Interest On Debt [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2017	85.4
Contractual Obligations, Payments Due by Period, 2018	92.9
Contractual Obligations, Payments Due by Period, 2019	88.9
Contractual Obligations, Payments Due by Period, 2020	84.3
Contractual Obligations, Payments Due by Period, 2021	79.4
Contractual Obligations, Payments Due by Period, Thereafter	280.5
Contractual Obligations, Payments Due by Period, Total	711.4
Total Debt Obligations [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2017	884.8
Contractual Obligations, Payments Due by Period, 2018	192.9
Contractual Obligations, Payments Due by Period, 2019	188.9
Contractual Obligations, Payments Due by Period, 2020	184.3
Contractual Obligations, Payments Due by Period, 2021	154.4
Contractual Obligations, Payments Due by Period, Thereafter	2,055.5
Contractual Obligations, Payments Due by Period, Total	3,660.8
Operating Lease Obligations [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2017	79.0
Contractual Obligations, Payments Due by Period, 2018	88.7
Contractual Obligations, Payments Due by Period, 2019	73.3
Contractual Obligations, Payments Due by Period, 2020	60.7
Contractual Obligations, Payments Due by Period, 2021	50.3
Contractual Obligations, Payments Due by Period, Thereafter	121.5
Contractual Obligations, Payments Due by Period, Total	473.5
Less Sublease Arrangements [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2017	(0.8)
Contractual Obligations, Payments Due by Period, 2018	(0.4)
Contractual Obligations, Payments Due by Period, 2019	(0.1)
Contractual Obligations, Payments Due by Period, 2020	(0.1)
Contractual Obligations, Payments Due by Period, Total	(1.4)
Outstanding Purchase Obligations [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2017	42.3
Contractual Obligations, Payments Due by Period, 2018	32.3
Contractual Obligations, Payments Due by Period, 2019	17.3
Contractual Obligations, Payments Due by Period, 2020	7.3
Contractual Obligations, Payments Due by Period, 2021	2.2
Contractual Obligations, Payments Due by Period, Total	101.4
Total Contractual Obligations [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2017	1,005.3
Contractual Obligations, Payments Due by Period, 2018	313.5
Contractual Obligations, Payments Due by Period, 2019	279.4
Contractual Obligations, Payments Due by Period, 2020	252.2
Contractual Obligations, Payments Due by Period, 2021	206.9
Contractual Obligations, Payments Due by Period, Thereafter	2,177.0
Contractual Obligations, Payments Due by Period, Total	$ 4,234.3

Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]

No definition available.

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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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=73718637&loc=d3e25383-109308

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Amount of the recorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of the recorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of the recorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of the recorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of the recorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of the recorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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