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Income Tax Expense - NOL and Tax Credit Carryforwards (Details) - USD ($) | Dec. 31, 2023 | Dec. 31, 2022
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Federal |  |
NOL and Tax Credit Carryforwards [Line Items] |  |
Tax Credit Carryforwards | $ 480,400,000 | $ 464,500,000
Federal Capital Loss Carryforwards | 0 | 35,100,000
Valuation allowance | 0 |
State |  |
NOL and Tax Credit Carryforwards [Line Items] |  |
Tax Credit Carryforwards | 21,500,000 | 24,500,000
NOL Carryforwards | 280,900,000 | 323,000,000.0
State Capital Loss Carryforwards | 0 | 83,200,000
Valuation allowance | 55,400,000 | 59,600,000
Valuation allowance | $ 10,500,000 |
State | Capital Loss Carryforward |  |
NOL and Tax Credit Carryforwards [Line Items] |  |
Valuation allowance |  | $ 58,700,000

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- Definition Federal Capital Loss Carryforwards + References No definition available. + Details
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- Definition NOL and Tax Credit Carryforwards [Line Items] + References No definition available. + Details
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- Definition State Capital Loss Carryforwards + References No definition available. + Details
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- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482685/740-10-50-3 + Details
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- Definition The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482685/740-10-50-2 + Details
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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://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482685/740-10-50-3 + Details
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- Definition Amount of valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from tax credit carryforwards for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482685/740-10-50-2 + Details
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