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Income Taxes (Narrative) (Details) - USD ($) | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Income Tax [Line Items] |  |  |  |
Net operating loss carryforward |  | $ 226,200,000 |  |
Valuation allowance increase | $ 6,700,000 |  |  |
Net deferred tax asset | 136,477,000 | 104,380,000 |  |
Unrecognized tax benefits | 3,962,000 | 3,387,000 | $ 312,000 | $ 3,180,000
Unrecognized tax benefits, accrued interest and penalties | 400,000 | 200,000 |  |
Accounts Payable and Accrued Expenses [Member] |  |  |  |
Income Tax [Line Items] |  |  |  |
Current taxes payable | 38,200,000 | 15,000,000.0 |  |
Other Assets [Member] |  |  |  |
Income Tax [Line Items] |  |  |  |
Current taxes receivable | $ 0 | $ 0 |  |

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- Definition Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
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