Goodwill and Intangible Assets - Gross Value and Net Carrying Amount (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Mar. 31, 2019
Amortizable intangible assets:
Gross Value	$ 85,172,000	$ 12,061,000
Accumulated Amortization	(17,456,000)	(10,633,000)
Impairment	(66,087,000)
Net Carrying Amount	1,629,000	1,428,000
Unamortizable intangible assets:
Gross Value	18,491,000	18,491,000
Accumulated Amortization	0	0
Net Carrying Amount	18,491,000	18,491,000
Developed technology | Noctiva
Amortizable intangible assets:
Gross Value	73,111,000	0
Accumulated Amortization	(7,024,000)	0
Net Carrying Amount	0	0
Developed technology | Vazculep
Amortizable intangible assets:
Gross Value	12,061,000	12,061,000
Accumulated Amortization	(10,432,000)	(10,633,000)
Net Carrying Amount	1,629,000	$ 1,428,000
In Process Research and Development [Member] | Noctiva
Amortizable intangible assets:
Impairment	(66,087,000)
In Process Research and Development [Member] | Vazculep
Amortizable intangible assets:
Impairment	$ 0