Stockholders' Equity - Warrants Issued to Service Provider (Details) - Common Stock Purchase Warrants - Service Provider - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		12 Months Ended
	Dec. 31, 2015	May 31, 2014	Dec. 31, 2015
Convertible Preferred Stock and Stockholders' Equity
Number of shares under warrant agreement (up to)	187,500	333,333
Exercise price of warrants (in dollars per share)		$ 12.81
Vesting period		4 years
Expiration period		5 years
Early expiration period		12 months
Outstanding common stock warrants	145,833		145,833
Total number of warrants earned under agreement			112,500
Selling and Marketing Expense
Convertible Preferred Stock and Stockholders' Equity
Reduction in warrant expense			$ 1.0
Minimum
Convertible Preferred Stock and Stockholders' Equity
Expected life			1 year
Risk-free interest rate			0.52%
Volatility (as a percent)			44.10%
Maximum
Convertible Preferred Stock and Stockholders' Equity
Expected life			4 years
Risk-free interest rate			1.28%
Volatility (as a percent)			48.90%