Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

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- Definition

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)

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- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 1A

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Borrowing Arrangements - Summary of Carrying Amount of Debt and Equity Components (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Sep. 27, 2010	May 30, 2006
2010 Convertible Senior Subordinated Notes [Member]
Debt Instrument [Line Items]
Principal amount of notes	$ 97,650,000	$ 130,000,000	$ 1,000
Unamortized discount	(1,831,000)	(5,494,000)
Net carrying amount	95,819,000	124,506,000
2006 Convertible Senior Subordinated Notes [Member]
Debt Instrument [Line Items]
Principal amount of notes	750,000	750,000		1,000
Net carrying amount	$ 750,000	$ 750,000