Fair Value Measurements - Summary of Changes in the Estimated Fair Value of Liability (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Dec. 31, 2013		Feb. 12, 2014
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning balance		$ 24,251	[1]
Ending balance	2,296	24,251	[1]
Convertible Preferred Stock Warranty Liability | Level 3
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning balance	24,251
Warrants exercised	(37,328)
Change in fair value	15,373
Ending balance	2,296
Contingent Consideration | Level 3
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning balance				1,310
Change in fair value	2,740
Ending balance	$ 4,050			$ 1,310

[1] Amounts have been derived from the December 31, 2013 audited financial statements included in the Company’s registration statement on Form S-1 (No. 333-198906) filed with the Securities and Exchange Commission on November 6, 2014