FINANCE LEASE LIABILITY, Obligations (Details) $ in Thousands	Jun. 30, 2020 USD ($) containership	Dec. 31, 2019 USD ($) containership
Other Liabilities Disclosure [Abstract]
Finance lease liability, current portion	$ 70,944	$ 68,874
Finance lease liability, long-term portion	1,002,558	1,037,553
Capital Lease Obligations	$ 1,073,502	$ 1,106,427
Commitments and Contingencies [Line Items]
Number of container vessels contracted to be chartered in \| containership	4	4
Number of container vessels under sale and leaseback transactions \| containership	7	7

Number of container vessels under sale and leaseback transactions

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Number of 19,200 20 TEU container vessels

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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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Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

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