Chartered-in Vessels - Capital Lease Obligations (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Capital Leased Assets [Line Items]
Finance lease, liability	$ 1,410,904
Capital lease obligations		$ 1,298,556
Less current portion	69,982
Less current portion		81,219
Long-term obligations related to finance leases	1,340,922
Long-term obligations related to finance leases		1,217,337
LNG Carriers
Capital Leased Assets [Line Items]
Finance lease, liability	1,410,904
Capital lease obligations		1,274,569
Suezmax Tanker
Capital Leased Assets [Line Items]
Finance lease, liability	$ 0
Capital lease obligations		$ 23,987

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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