Income Taxes (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Operating Loss Carryforwards [Line Items]
Deferred income taxes	$ 0	$ (508,000)
Deferred tax liabilities	2,785,000
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Taxable loss	(79,300,000)	(91,600,000)
Current income tax expense (benefit)		0
Operating loss carryforwards	647,500,000
Deferred tax assets, capital loss carryforwards	199,700,000
Research and development tax credits	10,000,000
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	71,900,000
Generated After 2017
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	394,800,000
Continuing Operations
Operating Loss Carryforwards [Line Items]
Deferred income taxes	0	(27,000)
Continuing Operations | Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Current income tax expense (benefit)	$ 40,000	$ 14,000