Income Taxes - Tax Credit Carryforwards (Details) $ in Millions	Dec. 31, 2019 USD ($)
Federal
Income Taxes
Operating loss carryforwards	$ 430.2
Federal \| General
Income Taxes
Tax credit carryforwards	6.4
State
Income Taxes
Operating loss carryforwards	298.3
Foreign
Income Taxes
Operating loss carryforwards	$ 2.0

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319

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