Schedule II - Valuation and Qualifying Accounts (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	$ 6.7	$ 6.6	$ 4.8
Amounts Recorded in Earnings	2.7	2.7	1.0
Adjustments	1.3	(2.6)	0.8
Balance at End of Year	10.7	6.7	6.6
Allowance for Estimated Policy Cancellations [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	4.2	4.0	5.2
Amounts Recorded in Earnings	(0.2)	(0.2)	(1.6)
Adjustments	2.8	0.4	0.4
Balance at End of Year	6.8	4.2	4.0
Accumulated Amortization of Expiration Lists, Noncompete Agreements and Trade Names [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	544.1	419.3	321.3
Amounts Recorded in Earnings	189.5	125.2	99.0
Adjustments	25.2	(0.4)	(1.0)
Balance at End of Year	$ 758.8	$ 544.1	$ 419.3

Valuation allowances and reserves, additions charged to earnings

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- Definition

Total of the adjustments in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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- Definition

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

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