Fair Value Measurements - Additional Information (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
Fair Value Disclosures [Abstract]
Fair value of asset transfer from Level 1 to Level 2 on recurring basis	$ 0	$ 0
Fair value of asset transfer from Level 2 to Level 1 on recurring basis	0	0
Fair value of liabilities transfer from Level 1 to Level 2 on recurring basis	0	0
Fair value of liabilities transfer from Level 2 to Level 1 recurring basis	0	0
Liabilities measured at estimated fair value on nonrecurring basis	$ 0	$ 0

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bb)

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

+ Details

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

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- Definition

Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

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- Definition

Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

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- Definition

Aggregation of the liabilities reported on the balance sheet measured at fair value on a nonrecurring basis by the entity.

+ References

No definition available.

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