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Long-Term Debt (Details 1) - USD ($) $ in Thousands	Dec. 31, 2018	Jun. 26, 2018	Dec. 31, 2017	Sep. 20, 2017	Mar. 15, 2017
Debt Instrument [Line Items]
Capital leases	$ 0		$ 25
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	(31,666)		(30,398)
Total long-term debt	2,284,834		2,858,620
less: current portion of long-term debt	6,000		5,525
Noncurrent portion of long-term debt	$ 2,278,834		2,853,095
Second Payment [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate stated percentage
Long-term Debt, Gross	$ 0		565,868
HFOTCO Credit Facility [Member]
Debt Instrument [Line Items]
Long-term Line of Credit		$ 75,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Interest Rate at Period End	2.75%
HFOTCO LLC [Member] \| Term Loan B [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate stated percentage	5.28%
Long-term Debt, Gross	$ 597,000	$ 600,000	532,125
HFOTCO LLC [Member] \| Tax Exempt Notes Payable due 2050 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate stated percentage	3.399%
Long-term Debt, Gross	$ 225,000		225,000
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%				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%			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
Long-term Line of Credit	$ 0		60,000
Alternate Base Rate [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	7.25%
Long-term Line of Credit	$ 24,500		0
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	5.156%
Long-term Line of Credit	$ 95,000		$ 131,000