Acquisitions (Schedule of Purchase Price Allocation) (Details) - USD ($) $ in Thousands	Jul. 24, 2015	Nov. 13, 2014
Enterprise Offshore Acquisition [Member]
Business Acquisition [Line Items]
Cash	$ 1,270
Accounts receivable	29,768
Inventories	600
Other current assets	10,432
Fixed assets	1,225,685
Intangible assets	79,050
Equity investees	352,535
Other assets	1,966
Accounts payable	(6,110)
Accrued liabilities	(18,662)
Other long-term liabilities	(161,412)
Noncontrolling interest	6,447
Total purchase price	$ 1,521,569
M/T American Phoenix Acquisition [Member]
Business Acquisition [Line Items]
Fixed assets		$ 125,000
Intangible assets		32,000
Total purchase price		$ 157,000

The amount of fair value assigned relating to noncontrolling interest acquired at the acquisition date.

No definition available.

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- Definition

Amount of fair value assigned to equity investees at the acquisition date.

+ References

No definition available.

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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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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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- Definition

Amount of other assets expected to be realized or consumed before one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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- Definition

Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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- Definition

Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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- Definition

The amount of inventory recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Amount of liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

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