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Commitments, Contingencies and Off-Balance Sheet Arrangements - Outstanding Letters of Credit, Financial Guarantees and Funding Commitments (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($)
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Maximum Exposure	$ 22.6
Liability Recorded	$ 18.3
Funding Commitment to an Equity Investment - to be Funded in 2022 [Member] | Other Investments [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Collateral	None
Compensation to Us	None
Maximum Exposure	$ 0.5
Credit Support Under Letters of Credit for Deductibles Due by Us on Our Own Insurance Coverage's Expires After 2025 [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Collateral	None
Compensation to Us	None
Maximum Exposure	$ 9.4
Liability Recorded	$ 18.3
Credit Enhancement Under Letters of Credit for Our Captive Insurance Operations to Meet Minimum Statutory Capital Requirement's Expires After 2025 [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Collateral	None
Compensation to Us	Reimbursement of LOC fees
Maximum Exposure	$ 6.1
Collateral Related to Claims Funds Held in a Fiduciary Capacity by a Recent Acquisition Expires 2021 [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Collateral	None
Compensation to Us	None
Maximum Exposure	$ 0.9
Credit Support under Letters of Credit in lieu of Security Deposits for two Leases from Acquisitions - Expires after 2023 and 2026 [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Collateral	None
Compensation to Us	None
Maximum Exposure	$ 0.6
Financial Guarantees of Loans to Five Canadian Based Employees Trigger [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Collateral	(1)
Compensation to Us	None
Maximum Exposure	$ 1.0
Financial Guarantee of External Loan to Subsidiary in Chile Expires when Loan Balance is Reduced to Zero through July 2024 - Principal and Interest are Paid Quarterly [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Collateral	None
Compensation to Us	None
Maximum Exposure	$ 4.1

X

- Definition

Collateral

+ References

No definition available.

+ Details

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- Definition

Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]

+ References

No definition available.

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- Definition

Compensation for commitments.

+ References

No definition available.

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- Definition

Liabilities Recorded on Self-Insurance

+ References

No definition available.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
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