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Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
SEC Schedule, 12-09, Allowance, Credit Loss [Member] |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |  |
Balance at Beginning of Year |  | $ 10.1 | $ 8.7 | $ 10.0
Amounts Recorded in Earnings |  | 7.0 | 6.6 | 4.2
Adjustments | [1] | (8.8) | (5.2) | (5.5)
Balance at End of Year |  | 8.3 | 10.1 | 8.7
Allowance for Estimated Policy Cancellations [Member] |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |  |
Balance at Beginning of Year |  | 9.9 | 8.3 | 7.8
Amounts Recorded in Earnings |  | (1.3) | 4.1 | 0.5
Adjustments | [2] | 1.4 | (2.5) |
Balance at End of Year |  | 10.0 | 9.9 | 8.3
Valuation Allowance for Deferred Tax Assets [Member] |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |  |
Balance at Beginning of Year |  | 94.9 | 80.5 | 67.4
Amounts Recorded in Earnings |  | 60.0 | 14.4 | 13.1
Balance at End of Year |  | 154.9 | 94.9 | 80.5
Accumulated Amortization of Expiration Lists, Non-compete Agreements and Trade Names [Member] |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |  |
Balance at Beginning of Year |  | 2,537.0 | 2,087.5 | 1,750.4
Amounts Recorded in Earnings |  | 415.1 | 417.3 | 334.0
Adjustments | [3] | (28.1) | 32.2 | 3.1
Balance at End of Year |  | $ 2,924.0 | $ 2,537.0 | $ 2,087.5
[1] | Net activity of bad debt write offs and recoveries and acquired businesses.
[2] | Additions to allowance related to acquired businesses.
[3] | Elimination of fully amortized expiration lists, non-compete agreements and trade names, intangible asset/amortization reclassifications and disposal of acquired businesses.

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