Long-Term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Capital leases	$ 27	$ 25
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	(29,734)	(30,398)
Long-term Debt and Capital Lease Obligations, Including Current Maturities	2,739,484	2,858,620
less: current portion of long-term debt	5,527	5,525
Long-term debt, net	$ 2,733,957	2,853,095
Second Payment [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	8.00%
Long-term Debt, Gross	$ 578,441	565,868
HFOTCO LLC [Member] \| Term Loan B [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.80%
Long-term Debt, Gross	$ 530,750	532,125
HFOTCO LLC [Member] \| Tax Exempt Notes Payable due 2050 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.816%
Long-term Debt, Gross	$ 225,000	225,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Interest Rate at Period End	2.25%
Senior Notes [Member] \| Senior Unsecured Notes due 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.625%
Long-term Debt, Gross	$ 400,000	400,000
Senior Notes [Member] \| Senior unsecured notes due 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.625%
Long-term Debt, Gross	$ 350,000	350,000
Senior Notes [Member] \| Senior Unsecured Notes due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.375%
Long-term Debt, Gross	$ 325,000	325,000
Senior Notes [Member] \| Senior Unsecured Notes due 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.25%
Long-term Debt, Gross	$ 300,000	300,000
Line of Credit [Member] \| Revolving Credit Facility [Member] \| HFOTCO Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Interest Rate at Period End	5.4033%
Long-term Line of Credit	$ 60,000	60,000
Eurodollar [Member] \| Line of Credit [Member] \| Revolving Credit Facility [Member] \| Corporate Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Interest Rate at Period End
Long-term Line of Credit	$ 0	$ 131,000

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.

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-Name Accounting Standards Codification
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