Long-Term Debt - Composition of Long-Term Debt (Details) - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Capital lease obligations related to real estate, maturing in varying amounts through December 2037, with a weighted average interest rate of 10.4% at September 30, 2018 and December 31, 2017	$ 51,418,000	$ 51,665,000
Long-term debt	1,379,085,000	1,357,712,000
Less current maturities of long-term debt	74,958,000	39,528,000
Long-term debt, net of current maturities	1,304,127,000	1,318,184,000
Acquisition Line
Debt Instrument [Line Items]
Acquisition line	32,584,000	26,988,000
5.00% Senior Notes
Debt Instrument [Line Items]
Senior notes	$ 543,306,000	542,063,000
Interest rate	5.00%
Aggregate principal amount	$ 550,000,000	550,000,000
5.25% Senior Notes
Debt Instrument [Line Items]
Senior notes	$ 296,587,000	296,151,000
Interest rate	5.25%
Aggregate principal amount	$ 300,000,000	300,000,000
Real estate related and other long-term debt
Debt Instrument [Line Items]
Real estate related and other long-term debt	$ 455,190,000	$ 440,845,000
Capital Lease Obligations
Debt Instrument [Line Items]
Weighted average interest rate	10.40%	10.40%

Long term debt and capital lease obligations excluding short term financing current.

No definition available.

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- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date.

+ References

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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- Definition

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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- Definition

Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

+ References

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- Definition

Amount of long-term debt classified as other.

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- Definition

Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

+ References

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