Fair Value of Financial Assets and Liabilities - Derivative Instruments (Change in Fair Value of Derivative and Warrant Liabilities) (Details)	6 Months Ended
	Jun. 30, 2016 USD ($)
Derivatives And Fair Value [Line Items]
Balance, warrant Liability	$ 6,000
Balance, Series B Redeemable Preferred Stock Liability	1,493,000
Dilutive Financing Derivative Liability [Member]
Derivatives And Fair Value [Line Items]
Balance, derivative liability
Creation of dilutive financing derivative	1,067,000
Changes in estimated fair value	634,000
Balance, derivative liability	156,000
Payout from liability	(1,545,000)
Series B redeemable convertible preferred stock [Member]
Derivatives And Fair Value [Line Items]
Balance, Series B Redeemable Preferred Stock Liability	1,493,000
Changes in estimated fair value	(1,493,000)
Balance, Series B Redeemable Preferred Stock Liability
Warrant Liability [Member]
Derivatives And Fair Value [Line Items]
Balance, warrant Liability	6,000
Changes in estimated fair value	6,000
June 2016 Offering Liability [Member]
Derivatives And Fair Value [Line Items]
Balance, derivative liability
Creation of dilutive financing derivative	1,816,000
Changes in estimated fair value	(506,000)
Balance, warrant Liability	1,310,000
Balance, derivative liability	$ 1,310,000