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Income Taxes (Narrative) (Details) - USD ($) | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | ---
Income Tax Contingency [Line Items] |  |  |
Valuation allowance | $ 19,191,000 | $ 18,445,000 |
Deferred tax assets expected to be realized | 130,800,000 |  |
Deferred tax assets, subject to expiration | 130,800,000 |  |
Deferred tax assets, not subject to expiration | 111,800,000 |  |
Unrecognized tax benefits, income tax penalties and interest accrued | 2,700,000 | 3,300,000 | $ 227,000
Unrecognized tax benefits that would impact effective tax rate | 19,100,000 | 20,400,000 | 15,200,000
Unrecognized tax benefits, income tax penalties and interest accrued that would impact effective tax rate | (366,000) | $ 1,400,000 | $ 193,000
Approximate range of uncertain income tax positions expected to be settled or resolved during the next 12 months, minimum | 83,000 |  |
Period through 2036 |  |  |
Income Tax Contingency [Line Items] |  |  |
Deferred tax assets, subject to expiration | 29,700,000 |  |
Federal and State | Period through 2029 |  |  |
Income Tax Contingency [Line Items] |  |  |
Tax credit carryforward, amount | $ 8,600,000 |  |

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