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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
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Dec. 31, 2018 USD ($)
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |
Maximum Exposure | $ 19.9
Liability Recorded | $ 15.8
Credit Support Under Letters of Credit for Deductibles Due by Us on Our Own Insurance Coverage's Expires After 2023 [Member] |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |
Collateral | None
Compensation to Us | None
Maximum Exposure | $ 10.2
Liability Recorded | $ 15.8
Credit Enhancement Under Letters of Credit for Our Captive Insurance Operations to Meet Minimum Statutory Capital Requirement's Expires After 2023 [Member] |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |
Collateral | None
Compensation to Us | Reimbursement of LOC fees
Maximum Exposure | $ 6.3
Collateral Related to Claims Funds Held in a Fiduciary Capacity by a Recent Acquisition Expires 2020 [Member] |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |
Collateral | None
Compensation to Us | None
Maximum Exposure | $ 1.3
Credit Support Under Letters of Credit in Lieu of Security Deposit for Acquisition Lease Expires 2023 [Member] |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |
Collateral | None
Compensation to Us | None
Maximum Exposure | $ 0.5
Financial Guarantees of Loans to Nineteen Canadian Based Employees Trigger [Member] |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |
Collateral | -1
Compensation to Us | None
Maximum Exposure | $ 1.6

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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 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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