Income Taxes, Tax Credit Carryforward (Details) $ in Millions	Dec. 31, 2016 USD ($)
Research and Development [Member] \| Federal [Member]
Tax Credit Carryforward [Abstract]
Tax credit carryforwards	$ 189.6
Research and Development [Member] \| California [Member]
Tax Credit Carryforward [Abstract]
Tax credit carryforwards	48.0
Federal [Member]
Operating Loss Carryforwards [Abstract]
Net operating loss carryforwards	679.8
California [Member]
Operating Loss Carryforwards [Abstract]
Net operating loss carryforwards	$ 973.1

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

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+ References

No definition available.

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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

+ Details

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+ References

No definition available.

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