Number of joint ventures in the company.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Amount of investment in equity method investee and investment in and advance to affiliate.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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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Equity Method Investments (Narrative) (Details) $ in Thousands	Jun. 30, 2019 USD ($) item	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Apr. 30, 2018 USD ($)	Jul. 14, 2017 USD ($)
Schedule of Equity Method Investments [Line Items]
Accumulated other comprehensive gain (loss)	$ (40,282)		$ (29,929)
Investments in and advances to affiliated companies	265,959		268,322
Current installments of long-term debt	$ 57,680		51,555
Number of joint ventures \| item	3
Other Equity Method Investments [Member]
Schedule of Equity Method Investments [Line Items]
Investments in and advances to affiliated companies	$ 16,441
LNG Joint Venture [Member] \| Liquid Natural Gas Carrier Vessel [Member]
Schedule of Equity Method Investments [Line Items]
Investments in and advances to affiliated companies	116,203
FSO Joint Venture [Member] \| FSO Term Loan [Member]
Schedule of Equity Method Investments [Line Items]
Line of credit facility, maximum borrowing capacity					$ 220,000
FSO Joint Venture [Member] \| FSO Term Loan [Member] \| Financial Guarantee [Member]
Schedule of Equity Method Investments [Line Items]
Line of credit facility, maximum borrowing capacity				$ 110,000
FSO Joint Venture [Member] \| FSO Asia and FSO Africa [Member]
Schedule of Equity Method Investments [Line Items]
Investments in and advances to affiliated companies	$ 133,315
LNG Joint Venture, TI Africa and TI Asia Limited [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	50.00%
Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Guarantor obligations, maximum exposure, undiscounted	$ 83,005		93,548
Guarantor obligations, current carrying value	$ 445	$ 445	$ 673