Income Taxes - Carryforward (Details) $ in Millions	Dec. 31, 2016 USD ($)
Research
Carryforward
Federal and state carryforwards	$ 46.9
Federal
Carryforward
Operating loss carryforward	476.4
Operating loss carryforward related to deductions from the exercise of stock options	27.0
State
Carryforward
Operating loss carryforward	308.3
Operating loss carryforward related to deductions from the exercise of stock options	$ 23.3

Represents the operating loss carryforward related to deductions from the exercise of stock options, before tax effects, available to reduce future taxable income under enacted tax laws.

No definition available.

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- Definition

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

+ References

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- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32559-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Carryforwards
-URI http://asc.fasb.org/extlink&oid=6506874

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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