Debt - Additional Information (Detail) - USD ($)					12 Months Ended
	Jan. 10, 2014	Dec. 20, 2013	Nov. 13, 2012	Oct. 01, 2012	Dec. 31, 2015	Dec. 31, 2013	Jun. 11, 2015	Dec. 31, 2012	Dec. 18, 2012	Mar. 01, 2012	Dec. 31, 2007
Debt Instrument [Line Items]
Long-term note payable						$ 400,000
Accrued interest						21,000
Debt extinguished	$ 400,000
Share price							$ 5.215
Convertible promissory notes						5,000,000		$ 5,000,000
Fair value of embedded derivative								$ 800,000
Amortized interest expense						800,000
Interest expense related to premium conversion feature						1,600,000
Convertible Notes Payable [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 5,000,000	$ 3,000,000						$ 1,000,000
Interest rate										8.00%
Accrued interest		$ 400,000
Debt maturity date			Dec. 31, 2013	Jun. 30, 2013
Conversion premium percentage			50.00%
Converted debt amount		5,000,000
Debt instrument beneficial conversion feature		$ 2,400,000
Outstanding borrowings on convertible promissory notes						$ 0
Redeemable Convertible Preferred Stock [Member]
Debt Instrument [Line Items]
Conversion of debt into shares	82,927	1,495,276
Share price	$ 5.215	$ 5.125
Conversion of debt into shares, amount		$ 7,800,000
Promissory Note [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity											$ 400,000
Interest rate											1.00%
Principal amount payable period					Payable over 59 months starting January 1, 2013
Premium on outstanding note balance in event of default					7.00%
Promissory Note [Member] | Amendment [Member]
Debt Instrument [Line Items]
Interest rate									5.00%
Principal amount payable period					The Company would be obligated to make payments on the restated principal on January 1, 2015 in monthly equal installments over 48 months if a qualified financing did not occur.