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Commitments, Contingencies and Off-Balance Sheet Arrangements - Additional Information (Detail) |  | 12 Months Ended | 192 Months Ended
--- | --- | --- | ---
Dec. 22, 2018 USD ($) Employee | Dec. 31, 2018 USD ($) ft² Entity LetterOfCredit Employees | Dec. 31, 2017 USD ($) Entity | Dec. 31, 2016 USD ($) Entity | Dec. 31, 2018 USD ($) ft² Entity LetterOfCredit
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |  |  |
Number of square feet | ft² |  | 360,000 |  |  | 360,000
Number of employees will accommodate at new facility | Employees |  | 2,000 |  |  |
Lease abandonment charges |  |  | $ 13,200,000 |  |
Total rent expense |  | $ 140,000,000 | $ 137,700,000 | $ 134,200,000 |
Number of companies acquired | Entity |  | 112 | 108 | 101 | 507
Aggregate amount of maximum earnout obligations related to acquisitions |  | $ 558,100,000 | $ 567,900,000 |  |
Aggregate amount of maximum earnout obligations related to acquisitions, recorded in consolidated balance sheet |  | $ 258,800,000 | $ 264,200,000 |  |
Ownership interest |  | 50.00% |  |  | 50.00%
Debt |  | $ 19,900,000 |  |  | $ 19,900,000
Liabilities recorded on self-insurance |  | $ 15,800,000 |  |  | 15,800,000
Definitive Agreement [Member] | Stackhouse Poland Group Limited [Member] | United Kingdom, Pounds |  |  |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |  |  |
Cash consideration | $ 350,000,000 |  |  |  |
Percentage of interest acquired in acquired entity | 100.00% |  |  |  |
Number of employees will accommodate at new facility | Employee | 500 |  |  |  |
Tax Increment Financing [Member] |  |  |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |  |  |
Property tax credit expect to receive period |  | 15 years |  |  |
Economic development for growing economy tax credit |  | $ 11,800,000 |  |  | 11,800,000
Letter of Credit [Member] |  |  |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |  |  |
Debt |  | $ 1,300,000 |  |  | $ 1,300,000
Number of letters of credit issued | LetterOfCredit |  | 1 |  |  | 1
Letter of Credit [Member] | Security Deposit [Member] |  |  |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |  |  |
Debt |  | $ 500,000 |  |  | $ 500,000
Number of letters of credit issued | LetterOfCredit |  | 1 |  |  | 1
Letter of Credit [Member] | Self-Insurance Deductibles [Member] |  |  |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |  |  |
Debt |  | $ 10,200,000 |  |  | $ 10,200,000
Liabilities recorded on self-insurance |  | $ 15,800,000 |  |  | $ 15,800,000
Number of letters of credit issued | LetterOfCredit |  | 2 |  |  | 2
Letter of Credit [Member] | Rent-A-Captive Facility [Member] |  |  |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |  |  |
Debt |  | $ 6,300,000 |  |  | $ 6,300,000
Number of letters of credit issued | LetterOfCredit |  | 7 |  |  | 7
Minimum [Member] |  |  |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |  |  |
Ownership interest |  | 1.00% |  |  | 1.00%
Minimum [Member] | Tax Increment Financing [Member] |  |  |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |  |  |
Property tax credit expect to receive |  | $ 60,000,000 |  |  | $ 60,000,000
Maximum [Member] |  |  |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |  |  |
Ownership interest |  | 50.00% |  |  | 50.00%
Maximum [Member] | Tax Increment Financing [Member] |  |  |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |  |  |
Property tax credit expect to receive |  | $ 90,000,000 |  |  | $ 90,000,000

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