Fair value portion of assets classified as held for sale.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

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Amount of currency on hand as well as demand deposits with banks or financial institutions. 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. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

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-Glossary Cash

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-Glossary Cash Equivalents

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- Definition

For an unclassified balance sheet, amounts due from an entity in which the reporting entity shares joint control with another party or group.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

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-Subparagraph (SX 210.4-08.(k)(1))

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-Topic 850

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- Definition

Fair value as of the balance sheet date of all derivative liabilities not designated as hedging instruments.

+ References

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-Topic 815

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

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-Glossary Loan

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Subparagraph (SX 210.9-03.16)

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- Definition

Fair value portion of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Financial Instruments - Summary of Fair Value and Carrying Value of Assets and Liabilities Measured on Recurring and Non-recurring Basis (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2012	Dec. 31, 2011
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	$ 37,708	$ 26,341	$ 18,554	$ 18,566
Loan to joint venture	9,830	9,830
Long-term debt, including current portion	(730,214)	(735,701)
Carrying Amount Asset/ (Liability) [Member] \| Fair Value Measurements, Recurring [Member] \| Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	37,708	26,341
Carrying Amount Asset/ (Liability) [Member] \| Fair Value Measurements, Recurring [Member] \| Level 2 [Member] \| Interest rate swaps [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap agreements	(26,724)	(33,631)
Carrying Amount Asset/ (Liability) [Member] \| Fair Value Measurements, Non-Recurring [Member] \| Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Vessels and equipment		252,068
Vessel held for sale		9,114
Carrying Amount Asset/ (Liability) [Member] \| Fair Value Measurements, Other [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loan to joint venture	9,830	9,830
Carrying Amount Asset/ (Liability) [Member] \| Fair Value Measurements, Other [Member] \| Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including current portion	(730,214)	(735,701)
Carrying Amount Asset/ (Liability) [Member] \| Fair Value Measurements, Other [Member] \| Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment in term loans and interest receivable	122,841	119,385
Fair Value Asset/ (Liability) [Member] \| Fair Value Measurements, Recurring [Member] \| Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	37,708	26,341
Fair Value Asset/ (Liability) [Member] \| Fair Value Measurements, Recurring [Member] \| Level 2 [Member] \| Interest rate swaps [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap agreements	(26,724)	(33,631)
Fair Value Asset/ (Liability) [Member] \| Fair Value Measurements, Non-Recurring [Member] \| Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Vessels and equipment		252,068
Vessel held for sale		9,114
Fair Value Asset/ (Liability) [Member] \| Fair Value Measurements, Other [Member] \| Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including current portion	(654,674)	(648,724)
Fair Value Asset/ (Liability) [Member] \| Fair Value Measurements, Other [Member] \| Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment in term loans and interest receivable	$ 119,929	$ 117,784