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Business Combinations - Summary of Estimated Fair Values of Net Assets Acquired (Detail) $ in Millions | Dec. 31, 2020 USD ($)
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Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Cash and restricted cash | $ 34.0
Other current assets | 88.0
Fixed assets | 3.2
Noncurrent assets | 27.6
Goodwill | 359.6
Expiration lists | 467.2
Non-compete agreements | 11.4
Trade names | 12.5
Total assets acquired | 1,003.5
Current liabilities | 103.6
Noncurrent liabilities | 23.8
Total liabilities assumed | 127.4
Total net assets acquired | 876.1
CRB [Member] |
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Noncurrent assets | 7.6
Goodwill | 108.4
Expiration lists | 133.7
Non-compete agreements | 2.9
Trade names | 4.7
Total assets acquired | 257.3
Total net assets acquired | 257.3
HES [Member] |
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Cash and restricted cash | 3.3
Other current assets | 1.0
Noncurrent assets | 0.8
Goodwill | 19.1
Expiration lists | 13.7
Non-compete agreements | 0.1
Total assets acquired | 38.0
Current liabilities | 4.4
Noncurrent liabilities | 0.5
Total liabilities assumed | 4.9
Total net assets acquired | 33.1
CRES [Member] |
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Cash and restricted cash | 4.3
Other current assets | 12.4
Goodwill | 21.3
Expiration lists | 13.9
Trade names | 0.3
Total assets acquired | 52.2
Current liabilities | 15.7
Total liabilities assumed | 15.7
Total net assets acquired | 36.5
OTI [Member] |
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Cash and restricted cash | 0.6
Other current assets | 3.0
Fixed assets | 0.9
Noncurrent assets | 6.7
Goodwill | 25.4
Expiration lists | 18.3
Non-compete agreements | 0.4
Total assets acquired | 55.3
Current liabilities | 5.2
Noncurrent liabilities | 7.5
Total liabilities assumed | 12.7
Total net assets acquired | 42.6
CIA [Member] |
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Cash and restricted cash | 4.2
Other current assets | 28.8
Fixed assets | 0.1
Noncurrent assets | 0.9
Goodwill | 58.9
Expiration lists | 56.2
Non-compete agreements | 0.8
Trade names | 7.5
Total assets acquired | 157.4
Current liabilities | 28.1
Noncurrent liabilities | 0.2
Total liabilities assumed | 28.3
Total net assets acquired | 129.1
HAI [Member] |
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Cash and restricted cash | 2.3
Other current assets | 9.0
Fixed assets | 1.1
Noncurrent assets | 6.4
Goodwill | 45.7
Expiration lists | 62.5
Non-compete agreements | 0.7
Total assets acquired | 127.7
Current liabilities | 9.5
Noncurrent liabilities | 6.4
Total liabilities assumed | 15.9
Total net assets acquired | 111.8
AT [Member] |
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Cash and restricted cash | 6.0
Other current assets | 8.6
Fixed assets | 0.5
Noncurrent assets | 2.1
Goodwill | 14.8
Expiration lists | 78.2
Non-compete agreements | 5.8
Total assets acquired | 116.0
Current liabilities | 8.4
Noncurrent liabilities | 2.1
Total liabilities assumed | 10.5
Total net assets acquired | 105.5
Twenty Other Acquisitions [Member] |
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Cash and restricted cash | 13.3
Other current assets | 25.2
Fixed assets | 0.6
Noncurrent assets | 3.1
Goodwill | 66.0
Expiration lists | 90.7
Non-compete agreements | 0.7
Total assets acquired | 199.6
Current liabilities | 32.3
Noncurrent liabilities | 7.1
Total liabilities assumed | 39.4
Total net assets acquired | $ 160.2

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