Fair Value of Financial Instruments - Summary of Change in Estimated Fair Value of Company's Level 3 Financial Instrument (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in the value of private placement warrants	$ (1,190)	$ 21,658
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Balance beginning	24,525
Fair value of private placement warrants exercised	(7,320)
Change in the value of private placement warrants	(1,190)
Balance ending	$ 16,015

Fair Value Measurement With Unobservable Inputs Change In Warrant Liability Due To Exercise Of Private Placement Warrants

No definition available.

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- Definition

Amount of increase (decrease) of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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