Commitments and Contingencies - Commitments to Fund Newbuilding and Other Construction Contract Costs (Details) - USD ($) $ in Thousands	1 Months Ended
Jun. 30, 2019	Sep. 30, 2021
Unrecorded Unconditional Purchase Obligation [Line Items]
Total estimated remaining costs		$ 31,896
Estimated Costs Remainder of 2020		5,843
Unrecorded Unconditional Purchase Obligation, to be Paid, Year One		26,053
Equity Method Investments [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Total estimated remaining costs		11,339
Estimated Costs Remainder of 2020		0
Unrecorded Unconditional Purchase Obligation, to be Paid, Year One		11,339
Consolidated Entities [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Total estimated remaining costs		20,557
Estimated Costs Remainder of 2020		5,843
Long-term Purchase Commitment, Amount	$ 53,500
Unrecorded Unconditional Purchase Obligation, to be Paid, Year One		$ 14,714
Bahrain LNG Joint Venture [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Equity Method Investment, Ownership Percentage		30.00%
Bahrain LNG Joint Venture [Member] \| Building
Unrecorded Unconditional Purchase Obligation [Line Items]
Line of credit facility, maximum borrowing capacity		$ 23,500
Line of Credit Facility, Remaining Borrowing Capacity		7,100
Bahrain LNG Joint Venture [Member] \| Construction [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Total estimated remaining costs		$ 11,300

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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The minimum amount the entity agreed to spend under the long-term purchase commitment.

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308

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Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in remainder of current fiscal year.

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