Future Operating Lease Payments as of Prior Year (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Leases [Abstract]
2019	$ 22.5	$ 22.2
2020	18.4	16.8
2021	15.0	12.6
2022	10.7	10.2
2023	7.2	8.1
Thereafter	54.4	46.4
Total minimum lease payments	$ 128.2	$ 116.3

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- Definition

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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-Publisher FASB
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-Topic 840
-SubTopic 20
-Section 50
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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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.

+ References

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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 required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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 required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
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Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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-SubTopic 20
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-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41502-112717

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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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