Acquisition of GCI - Summary of Value of Attributed to Identifiable Assets Acquired and Liabilities Assumed (Detail) - GCI [Member] $ in Thousands	Mar. 13, 2018 USD ($)
Business Acquisition [Line Items]
Cash and cash equivalents	$ 70,121
Current assets	5,316
Vessels	1,369,628
Vessels under construction	28,924
Other assets	107,407
Total assets acquired	1,581,396
Debt assumed	1,038,081
Current liabilities	31,115
Other long-term liabilities	14,150
Net assets acquired	$ 498,050

Business combination recognized identifiable assets acquired and liabilities assumed vessels under construction.

No definition available.

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- Definition

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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No definition available.

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Amount of assets acquired at the acquisition date.

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- Definition

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 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 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 long-term debt due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=84160947&loc=d3e2207-128464

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-Topic 805
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-Section 50
-Paragraph 1
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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 other 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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