Total lease liabilities

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Total leased assets.

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount of interest expense on finance lease liability.

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Present value of lessee's discounted obligation for lease payments from finance lease.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in third fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in second fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for finance lease.

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Amount of cash outflow for principal payment on finance lease.

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Amount of lessee's right to use underlying asset under finance lease.

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Amount of amortization expense attributable to right-of-use asset from finance lease.

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Weighted average discount rate for finance lease calculated at point in time.

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Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of lease cost recognized by lessee for lease contract.

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Amount of lessee's undiscounted obligation for lease payments for operating lease.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fourth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Amount of lessee's right to use underlying asset under operating lease.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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LEASES Leases (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
LEASES Leases (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Lessee, Lease, Details [Line Items]
Operating cash flows for operating leases		$ 3,300
Financing cash flows for finance lease		860
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability		3,041
Finance lease assets- Accumulated depreciation	$ (3,470,520)	(3,470,520)		$ (3,264,312)
Finance lease liability - current	1,854	1,854		1,765
Finance lease liability - noncurrent	25,294	25,294		$ 26,244
Lease Assets and Liabilities Included in the Consolidated Balance Sheet
Lessee, Lease, Details [Line Items]
Operating lease assets- Other assets	17,406	17,406
Finance lease assets- PPE	28,286	28,286
Finance lease assets- Accumulated depreciation	(754)	(754)
Total leased assets	44,938	44,938
Operating lease liabilities- Other current liabilities	3,660	3,660
Finance lease liability - current	1,854	1,854
Operating lease liabilities- Other deferred credits	13,964	13,964
Finance lease liability - noncurrent	25,294	25,294
Total lease liabilities	44,772	44,772
Components of Lease Cost
Lessee, Lease, Details [Line Items]
Operating leases	1,921	3,651
Amortization of lease assets	283	566
Interest on lease liabilities	686	1,383
Total lease cost	$ 2,890	$ 5,600
Weighted-Average Remaining Lease Term
Lessee, Lease, Details [Line Items]
Operating leases	9 years 9 months 18 days	9 years 9 months 18 days
Finance lease	9 years 3 months 18 days	9 years 3 months 18 days
Weighted-Average Discount Rate
Lessee, Lease, Details [Line Items]
Operating leases	4.58%	4.58%
Finance lease	10.00%	10.00%
Maturity of Finance Lease Liability
Lessee, Lease, Details [Line Items]
Remainder of 2019	$ 2,200	$ 2,200
2020	4,500	4,500
2021	4,500	4,500
2022	4,500	4,500
2023	4,500	4,500
2024 and beyond	21,600	21,600
Total lease payments	41,800	41,800
Less: Interest	14,700	14,700
Present value of lease liabilities	27,100	27,100
Maturity of Operating Lease Liabilities
Lessee, Lease, Details [Line Items]
Remainder of 2019	4,300	4,300
2020	2,200	2,200
2021	1,900	1,900
2022	1,800	1,800
2023	1,800	1,800
2024 and beyond	10,100	10,100
Total lease payments	22,100	22,100
Less: Interest	4,500	4,500
Present value of lease liabilities	$ 17,600	$ 17,600
Accounting Standards Update 2016-02
Lessee, Lease, Details [Line Items]
Present value of lease liabilities			$ 17,400
Operating lease assets- Other assets			$ 17,500