Business Combination - Schedule of Preliminary Estimate of Purchase Price (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Business Acquisition [Line Items]
Adjustment		$ (14,600)	$ 0
Viventia Bio, Inc.
Business Acquisition [Line Items]
Shares Issued	$ 13,525			$ 13,525
Contingent Consideration	31,600			46,200
Fair Value of Consideration	45,125			$ 59,725
Adjustment	$ (14,600)