LEASE - Finance leases - Gross difference (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Finance leases, gross difference
Total future minimum lease payments	$ 41,130
Less: imputed interest	2,056
NPV for future minimum lease payments	$ 39,074
Total future minimum lease payments		$ 76,826
Less: imputed interest		5,024
NPV for future minimum lease payments		$ 71,802

Amount of minimum lease payments for capital leases.

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Amount necessary to reduce net minimum lease payments to present value for capital leases.

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
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-Publisher FASB
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Amount of lessee's undiscounted obligation for lease payments for finance lease.

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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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