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 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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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.

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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	9 Months Ended
LEASES Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Lessee, Lease, Details [Line Items]
Operating cash flows for operating leases		$ 4,972
Financing cash flows for finance lease		1,307
Right-of-use asset obtained in exchange for operating lease liability		3,663
Finance lease assets- Accumulated depreciation	$ (3,585,411)	(3,585,411)		$ (3,264,312)
Finance lease liability - current	1,901	1,901		1,765
Finance lease liability - noncurrent	24,801	24,801		$ 26,244
Lease Assets and Liabilities Included in the Consolidated Balance Sheet
Lessee, Lease, Details [Line Items]
Operating lease assets- Other assets	16,176	16,176
Finance lease assets- PPE	28,286	28,286
Finance lease assets- Accumulated depreciation	(1,037)	(1,037)
Total leased assets	43,425	43,425
Operating lease liabilities- Other current liabilities	2,624	2,624
Finance lease liability - current	1,901	1,901
Operating lease liabilities- Other deferred credits	13,790	13,790
Finance lease liability - noncurrent	24,801	24,801
Total lease liabilities	43,116	43,116
Components of Lease Cost
Lessee, Lease, Details [Line Items]
Operating leases - Operations and maintenance	1,751	5,402
Finance lease - Amortization of lease assets	283	849
Finance lease - Interest on lease liabilities	675	2,058
Total lease cost	$ 2,709	$ 8,309
Weighted-Average Remaining Lease Term
Lessee, Lease, Details [Line Items]
Operating leases	10 years 1 month 6 days	10 years 1 month 6 days
Finance lease	9 years 1 month 6 days	9 years 1 month 6 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	$ 1,100	$ 1,100
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	40,700	40,700
Less: Interest	14,000	14,000
Present value of lease liabilities	26,700	26,700
Maturity of Operating Lease Liabilities
Lessee, Lease, Details [Line Items]
Remainder of 2019	1,300	1,300
2020	2,400	2,400
2021	2,000	2,000
2022	2,000	2,000
2023	1,900	1,900
2024 and beyond	11,100	11,100
Total lease payments	20,700	20,700
Less: Interest	4,300	4,300
Present value of lease liabilities	$ 16,400	$ 16,400
Accounting Standards Update 2016-02
Lessee, Lease, Details [Line Items]
Present value of lease liabilities			$ 17,400
Operating lease assets- Other assets			$ 17,500