Summary of Long-Term Debt (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Accounts receivable securitization program	$ 330,000,000
Long-term debt	3,278,534,000us-gaap_LongTermDebt	3,309,074,000us-gaap_LongTermDebt
Less-Amounts due within one year	(68,319,000)	(99,312,000)
Long-term debt, net	3,210,215,000us-gaap_LongTermDebtNoncurrent	3,209,762,000us-gaap_LongTermDebtNoncurrent
Notes Payable And Mortgages Payable
Debt Instrument [Line Items]
Notes payable and Mortgages payable (including obligations under capitalized leases of $21,600 in 2014 and $6,633 in 2013) and term loans with varying maturities through 2037; weighted average interest rates of 6.4% in 2014 and 5.9% in 2013 and 2012 (see Note 7 regarding capitalized leases)	41,257,000	37,553,000
Revolving Credit And Demand Notes
Debt Instrument [Line Items]
Line of credit facility amount outstanding	140,500,000	25,500,000
Term Loan A
Debt Instrument [Line Items]
Line of credit facility amount outstanding	1,761,872,000	935,308,000
Term Loan B Facility
Debt Instrument [Line Items]
Line of credit facility amount outstanding	0	543,527,000
Term Loan- A2
Debt Instrument [Line Items]
Line of credit facility amount outstanding	0	871,875,000
Revenue Bonds
Debt Instrument [Line Items]
Revenue bonds, interest at floating rates of 0.05% at December 31, 2014 and 0.1% at December 31, 2013, with varying maturities through 2015	5,300,000	5,300,000
Accounts Receivable Securitization Program
Debt Instrument [Line Items]
Accounts receivable securitization program	330,000,000	240,000,000
3.750% Senior Secured Notes due 2019
Debt Instrument [Line Items]
Senior Notes	299,802,000	0
4.750% Senior Secured Notes due 2022
Debt Instrument [Line Items]
Senior Notes	299,796,000	0
7.125% Senior Secured Notes due 2016
Debt Instrument [Line Items]
Senior Notes	400,007,000	400,011,000
7.00% Senior Unsecured Notes due 2018
Debt Instrument [Line Items]
Senior Notes	$ 0	$ 250,000,000

Notes and mortgages payable.

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Revenue bonds.

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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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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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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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