Fair Value of Financial Instruments (Tables)

9 Months Ended

Sep. 30, 2017

Fair Value Disclosures [Abstract]

Fair Value of Financial Instruments

Financial Liabilities — The following tables set forth the fair value of the Company’s financial instruments (in millions):

	As of September 30, 2017
			Fair Value Measurements Using
	Carrying Value				(Level 1)		(Level 2)		(Level 3)		Fair Value
Financial liabilities:
Senior convertible notes	$	27.7		$		—	$	—	$	24.7	$	24.7
Facility financing obligation		57.9				—		—		60.0		60.0
Milestone rights		8.9				—		—		18.7		18.7
Total financial liabilities	$	94.5		$		—	$	—	$	103.4	$	103.4

	As of December 31, 2016
			Fair Value Measurements Using
	Carrying Value		(Level 1)		(Level 2)		(Level 3)		Fair Value
Financial liabilities:
Senior convertible notes	$	27.6	$	—	$	—	$	22.9	$	22.9
Facility financing obligation		71.3		—		—		74.5		74.5
Milestone rights		8.9		—		—		18.4		18.4
Warrant liability (at recurring fair value)		7.4		—		—		7.4		7.4
Total financial liabilities	$	115.2	$	—	$	—	$	123.2	$	123.2

Fair Values of Warrant Liability which Include Level 3 Instruments

The following table provides a roll forward of the fair value of the warrant liability which is the only Level 3 financial instrument that is carried at fair value (in millions):

Balance at beginning of period December 31, 2016	$	7.4
Additions		—
Changes in fair value		(5.5	)
Settlement through exchange for common shares		(1.9	)
Payments		—
Fair value, end of period September 30, 2017	$	0.0