Long-Term Debt and Notes Payable - Summary of Long-Term Debt Obligations (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Long-term debt consists of:
Long-term borrowing	$ 861,339us-gaap_DebtAndCapitalLeaseObligations	$ 864,469us-gaap_DebtAndCapitalLeaseObligations
Less: Amounts due within one year	27,092	27,026
Long-Term Debt	834,247	837,443
Senior Notes [Member]
Long-term debt consists of:
Long-term borrowing	490,625	490,354
Term Loan [Member]
Long-term debt consists of:
Long-term borrowing	291,040	291,424
Amortizing Notes [Member]
Long-term debt consists of:
Long-term borrowing	30,354	33,258
Capital lease obligation [Member]
Long-term debt consists of:
Long-term borrowing	2,802	2,802
Other financing [Member]
Long-term debt consists of:
Long-term borrowing	494	743
North Ocean 105 [Member]
Long-term debt consists of:
Long-term borrowing	$ 46,024	$ 45,888

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13,16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal 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 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section H

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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