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Income Taxes (Narrative) (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Income Tax Contingency [Line Items] |  |  |  |
Federal tax rate |  | 21.00% | 21.00% | 35.00%
Tax Cuts and Jobs Act of 2017, maximum operating loss carryforwards percentage |  | 80.00% |  |
Tax Cuts and Jobs Act of 2017, change in tax rate, deferred tax liability, income tax (expense) benefit | $ 2,900,000 |  |  | $ 2,900,000
Interest or penalties recorded in income statement |  | $ 0 | $ 0 | $ 0
Amounts accrued for interest or penalties |  | 0 | $ 0 |
Domestic Country [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Operating loss carryforwards |  | 0 |  |
State And Local Jurisdiction [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Operating loss carryforwards |  | $ 0 |  |
Minimum [Member] | Domestic Country [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Federal income tax years currently open for audits |  | 2016 |  |
Minimum [Member] | State And Local Jurisdiction [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Federal income tax years currently open for audits |  | 2017 |  |
Maximum [Member] | Domestic Country [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Federal income tax years currently open for audits |  | 2019 |  |
Maximum [Member] | State And Local Jurisdiction [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Federal income tax years currently open for audits |  | 2019 |  |
Scenario, Plan [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Federal tax rate |  | 21.00% |  |

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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 + Details
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