Identification of the name or type of counterparty to the derivative instrument.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column A

-Footnote 1

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Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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- Definition

States whether the entity was in compliance with the debt covenants throughout the reporting period, and describes facts and circumstances of any compliance failure.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph (g)

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- Definition

The amount of cash or securities placed with a broker or counterparty as security for a trading or derivatives securities position which was partially obtained with funds provided by the broker dealer.

+ 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 210.5-02.8,17)

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

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Subsequent Events - Additional Information (Detail) (USD $)	3 Months Ended	0 Months Ended	1 Months Ended
	Mar. 31, 2015 Segments	May 28, 2015 Segments	May 31, 2015
Subsequent Event [Line Items]
Number of operating segments	1us-gaap_NumberOfOperatingSegments
Subsequent Event [Member]
Subsequent Event [Line Items]
Number of operating segments		2
Subsequent Event [Member] \| Zero cost collars [Member]
Subsequent Event [Line Items]
Derivative counterparty			Nomura Financial Investment (Korea) Co., Ltd.
Derivative notional amount			$ 84,000,000
Deposit paid to counterparty			$ 5,000,000
6.625% senior notes due 2021 [Member] \| Senior notes [Member]
Subsequent Event [Line Items]
Debt instrument, covenant terms	The Company did not cure the Initial Reporting Defaults within the applicable 60-day grace period and the Initial Reporting Defaults ripened into Events of Default.
6.625% senior notes due 2021 [Member] \| Senior notes [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Debt instrument, covenant terms		The Company believes it has cured the default referenced in the 10-K Notice of Default within the applicable 60-day grace period under the Indenture by the filing of the 2014 10-K with the SEC on May 28, 2015.