Warrants - Information (Details) - USD ($)							1 Months Ended					3 Months Ended	12 Months Ended
	Dec. 05, 2019	Nov. 26, 2018	Dec. 11, 2017	Dec. 04, 2017	Nov. 03, 2014	Oct. 29, 2013	Dec. 31, 2019	Sep. 30, 2019	Aug. 31, 2019	Jan. 31, 2019	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jul. 25, 2019	Mar. 31, 2019	Dec. 31, 2016	Nov. 09, 2016
Class of Warrant or Right [Line Items]
Warrants issued													58,334	15,750	1,890,602
Exercise price of warrants (in dollars per share)							$ 7.21				$ 5.21	$ 7.21	$ 7.21	$ 6.35	$ 5.21			$ 3.06
Warrants exercised													111,715	101,310	129,149
Exercised (in dollars per share)													$ 6.73	$ 1.30	$ 1.30
Shares issued	207,400,000									3,164,015	1,783,587	89,390	942,285
Warrants outstanding							69,656				2,099,199	69,656	69,656	123,037	2,099,199			337,746
Common warrants
Class of Warrant or Right [Line Items]
Warrants issued		15,750	1,783,587	1,783,587
Exercise price of warrants (in dollars per share)		$ 3.06	$ 5.25	$ 5.25
Warrant term		7 years
Warrants exercised									7,875
Shares issued									6,969
Warrants outstanding							7,875					7,875	7,875
Placement agent warrants
Class of Warrant or Right [Line Items]
Warrants issued			107,015	107,015
Exercise price of warrants (in dollars per share)			$ 6.6562	$ 6.6562
Warrant term			1 year
Shares issued											107,015
2013 Warrants
Class of Warrant or Right [Line Items]
Warrant term						5 years	5 years					5 years	5 years
Warrants exercised														101,310	129,149
Exercised (in dollars per share)						$ 1.30
Common stock to be issued if warrants are exercised (in shares)						230,459
Term Loan
Class of Warrant or Right [Line Items]
Exercise price of warrants (in dollars per share)																			$ 7.41
Warrant term																			7 years
Warrants exercised								32,614
Shares issued								24,328
Warrants outstanding							32,164					32,164	32,164
Common stock to be issued if warrants are exercised (in shares)																			65,228
2019 Term Loan
Class of Warrant or Right [Line Items]
Shares issued							24,185
Warrants outstanding							29,167					29,167	29,167
2019 Term Loan | Warrants
Class of Warrant or Right [Line Items]
Exercise price of warrants (in dollars per share)																	$ 8.10
Warrants exercised							29,167
Common stock to be issued if warrants are exercised (in shares)																29,167	70,000
Term Loan 2019, Tranche Two | Warrants
Class of Warrant or Right [Line Items]
Exercise price of warrants (in dollars per share)																$ 25.71
Common stock to be issued if warrants are exercised (in shares)																5,750
September 2014 Notes
Class of Warrant or Right [Line Items]
Exercise price of warrants (in dollars per share)					$ 5.94
Warrant term					5 years
Warrants exercised													42,059
Common stock to be issued if warrants are exercised (in shares)					42,059
Fair value of warrant recorded as a debt discount					$ 79,129
Mandatory conversion, warrant price premium as a percent of the conversion price					10.00%