Summary of Long-Term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Accounts receivable securitization program	$ 420,000
Total debt before unamortized financing costs	4,059,238	$ 4,161,699
Less-Unamortized financing costs	(19,229)	(25,574)
Total debt after unamortized financing costs	4,040,009	4,136,125
Less-Amounts due within one year (net of unamortized financing costs)	(545,619)	(105,895)
Long-term debt	3,494,390	4,030,230
Term Loan A
Debt Instrument [Line Items]
Line of credit facility amount outstanding	1,774,607	1,862,915
Accounts Receivable Securitization Program
Debt Instrument [Line Items]
Accounts receivable securitization program	419,500	398,700
3.75% Senior Secured Notes due 2019
Debt Instrument [Line Items]
Senior Notes	299,931	299,888
4.75% Senior Secured Notes due 2022
Debt Instrument [Line Items]
Senior Notes	704,306	705,250
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 $21,780 in 2017 and $23,446 in 2016) and term loans with varying maturities through 2027; weighted average interest rates of 9.1% in 2017 and 8.9% in 2016 (see Note 7 regarding capitalized leases)	22,794	25,246
Revolving Credit And Demand Notes
Debt Instrument [Line Items]
Line of credit facility amount outstanding	$ 438,100	$ 469,700

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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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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This is the principal amount outstanding for securitized loans only (across all types of loans).

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Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

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