Income Taxes - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
U.S. federal corporate income tax rate (percent)	21.00%
Net operating loss carryforwards	$ 246.0	$ 225.0
Market capitalization used in net operating loss analysis	125.0
Limitation on loss carryforward based Section 382 change in ownership	$ 3.0

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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