Summary of Long-Term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Accounts receivable securitization program	$ 390,000
Total debt before unamortized financing costs	4,019,822	$ 4,059,238
Less-Unamortized financing costs	(21,189)	(19,229)
Total debt after unamortized financing costs	3,998,633	4,040,009
Less-Amounts due within one year (net of unamortized financing costs)	(63,446)	(545,619)
Long-term debt	3,935,187	3,494,390
Term Loan A
Debt Instrument [Line Items]
Line of credit facility amount outstanding	2,000,000	1,774,607
Term Loan B
Debt Instrument [Line Items]
Line of credit facility amount outstanding	500,000
Accounts Receivable Securitization Program
Debt Instrument [Line Items]
Accounts receivable securitization program	390,000	419,500
3.75% Senior Secured Notes due 2019
Debt Instrument [Line Items]
Senior Notes		299,931
4.75% Senior Secured Notes due 2022
Debt Instrument [Line Items]
Senior Notes	703,363	704,306
5.00% Senior Secured Notes due 2026
Debt Instrument [Line Items]
Senior Notes	400,000	400,000
Notes Payable And Mortgages Payable
Debt Instrument [Line Items]
Notes payable and Mortgages payable (including obligations under capitalized leases of $19,941 in 2018 and $21,780 in 2017) and term loans with varying maturities through 2027; weighted average interest rates of 9.5% in 2018 and 9.1% in 2017 (see Note 7 regarding capitalized leases)	20,159	22,794
Revolving Credit And Demand Notes
Debt Instrument [Line Items]
Line of credit facility amount outstanding	$ 6,300	$ 438,100

Notes and mortgages payable.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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.

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

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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