Number of Impaired Assets

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- Definition

Number of Vessels

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- Definition

Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]

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- Definition

Percentage of completion

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- Definition

Restricted Cash Foreign Accounts

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- Definition

Restricted Cash Reinsurance Reserves

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- Definition

Accumulated appreciation or loss, net of tax, in value of the total of available-for-sale securities at the end of an accounting period.

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- Definition

The charge against earnings resulting from the aggregate write down of all assets from their carrying value to their fair value.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-SubTopic 10

-Section 45

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

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Cash and equivalents whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements.

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BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Additional information (Detail) (USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2010	Sep. 30, 2010	Sep. 30, 2011	Dec. 31, 2010
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Percentage of completion to recognize expected profit			70.00%
Restricted cash and cash equivalents, aggregate amount			$ 15,300,000
Restricted cash and cash equivalents, restricted foreign accounts			13,800,000
Restricted cash and cash equivalents, reinsurance reserve requirements			500,000
Restricted cash and cash equivalents, non-current			1,000,000
Available-for-sale securities			200,946,000	285,205,000
Net loss on investments			(4,426,000)	(4,330,000)
Loss on asset impairments	$ 24,444,000	$ 24,444,000
Charter Fleet Business
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of vessels	10
Secunda International Limited
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of vessels	14
Number of assets impaired	2
Secunda International Limited \| Vessels retain for use
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of vessels	4