STOCKHOLDERS' DEFICIT - Preferred Stock (Details) - $ / shares	Mar. 31, 2017	Dec. 31, 2016	Oct. 06, 2016	Jul. 13, 2016
Class of Stock [Line Items]
Preferred stock, par value (in dollars per share)	$ 0.0001
Preferred stock, shares authorized (in shares)	25,000,000
Series A Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	750,000	750,000
Preferred stock, shares outstanding (in shares)	60,756	125,044	165,541
Series B-1 Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	2,000
Preferred stock, shares outstanding (in shares)	0
Series B-2 Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	1,000
Preferred stock, shares outstanding (in shares)	0
Series C Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	690
Preferred stock, shares outstanding (in shares)	0
Series D Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	3,000
Preferred stock, shares outstanding (in shares)	0
Series D-1 Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	2,500
Preferred stock, shares outstanding (in shares)	0
Series E Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	2,800
Preferred stock, shares outstanding (in shares)	105
Series F Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	7,000
Preferred stock, shares outstanding (in shares)	160
Series G Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	2,000
Preferred stock, shares outstanding (in shares)	736
Series H Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	2,500
Preferred stock, shares outstanding (in shares)	0			830
Series I Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	1,000
Preferred stock, shares outstanding (in shares)	0
Series J Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	1,350
Preferred stock, shares outstanding (in shares)	1,125
Series J-1 Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	700	700
Preferred stock, shares outstanding (in shares)	700	700
Series K Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	20,000
Preferred stock, shares outstanding (in shares)	150