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Description of debt redemption features under terms of the debt agreement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph e

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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-Publisher FASB

-Name Accounting Standards Codification

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Indebtedness - Senior Subordinated Notes and Early Extinguishment of Debt - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended			0 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014 Subordinated Debt	May 27, 2014 8.0% Senior Subordinated notes due 2019
Debt Instrument [Line Items]
Maximum redemption price of notes as percentage of principal amount					101.00%	104.00%
Announced call for redemption amount of debt						$ 300,000,000
Debt instrument, redemption description						On May 27, 2014, we announced a call for the redemption of $300.0 million of our outstanding 8.0% senior subordinated notes due 2019 at 104.0% of par plus accrued and unpaid interest, which were redeemed on June 26, 2014.
Loss on early extinguishment of debt	$ 24,596,000	$ 12,280,000	$ 24,596,000	$ 12,280,000