Commitments And Contingencies [Line Items]

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- Definition

Long-Term Purchase Commitment, Number Of Payment Installments

+ References

No definition available.

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- Definition

The percentage due of the amount the entity agreed to spend under the long-term purchase commitment.

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No definition available.

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- Definition

Number Of Chartered Vessels

+ References

No definition available.

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- Definition

Term of charter agreement in years.

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No definition available.

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- Definition

The duration period applicable to the contract.

+ References

No definition available.

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- Definition

Carrying value of amounts transferred to third parties for security purposes that are expected to be returned or applied towards payment after one year or beyond the operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The minimum amount the entity agreed to spend under the long-term purchase commitment.

+ References

No definition available.

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- Definition

The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585

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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Commitments And Contingencies And Other Matters (Narrative) (Details) $ in Thousands	1 Months Ended					9 Months Ended
	Oct. 21, 2016 USD ($)	Dec. 31, 2015 USD ($) payment_installment	Jul. 31, 2015 USD ($)	Feb. 28, 2014 vessel	Sep. 30, 2013 USD ($)	Sep. 30, 2016 USD ($)	Nov. 30, 2014 USD ($)
Commitments And Contingencies [Line Items]
Total investment		$ 2,544,857				$ 2,655,343
Charter fee deposit		$ 12,544				12,544
Q7000 [Member]
Commitments And Contingencies [Line Items]
Contract amount					$ 346,000
Percentage of contract price to be paid		80.00%
Number of installments to be paid \| payment_installment		3
Total investment						190,100
Q7000 [Member] \| Contract Signing [Member]
Commitments And Contingencies [Line Items]
Percentage of contract price to be paid					20.00%
Payment of shipyard costs						69,200
Q7000 [Member] \| Due June 2016 [Member]
Commitments And Contingencies [Line Items]
Percentage of contract price to be paid		20.00%
Q7000 [Member] \| Issuance of Completion Certificate [Member]
Commitments And Contingencies [Line Items]
Percentage of contract price to be paid		20.00%
Q7000 [Member] \| Vessel Delivery [Member]
Commitments And Contingencies [Line Items]
Percentage of contract price to be paid		40.00%
Q7000 [Member] \| Capital Addition Purchase Commitments [Member] \| Extend Scheduled Delivery [Member]
Commitments And Contingencies [Line Items]
Total investment					$ 14,500
Q7000 [Member] \| Capital Addition Purchase Commitments [Member] \| Contract Signing [Member] \| Extend Scheduled Delivery [Member]
Commitments And Contingencies [Line Items]
Payment of shipyard costs			$ 7,300
Monohull Vessels [Member]
Commitments And Contingencies [Line Items]
Number of chartered vessels \| vessel				2
Topside Equipment [Member]
Commitments And Contingencies [Line Items]
Total investment						$ 179,500
Siem Helix 2 [Member]
Commitments And Contingencies [Line Items]
Charter fee deposit							$ 12,500
Siem [Member] \| Monohull Vessels [Member]
Commitments And Contingencies [Line Items]
Term of charter agreement				7 years
Petrobras [Member]
Commitments And Contingencies [Line Items]
Term of contract				4 years
Subsequent Event [Member] \| Q7000 [Member]
Commitments And Contingencies [Line Items]
Payment of shipyard costs	$ 69,200