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Income Taxes - Additional Information (Details) - USD ($) $ in Thousands | 12 Months Ended |
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Dec. 31, 2020 | Dec. 31, 2019
Income Tax Contingency [Line Items] |  |
Change in net deferred tax liabilities | $ 4,183 |
Unrecognized tax benefits before impact of deductions for state taxes, excluding interest and penalties | 6,468 | $ 4,037
Unrecognized tax benefits that would impact effective tax rate | 5,600 | $ 3,511
Accrued interest, expense net of the benefit of tax deductions | 107 |
Cumulative reduction in unrecognized tax benefits, due to lapsing of statutes of limitations | 80 |
Connecticut |  |
Income Tax Contingency [Line Items] |  |
Operating loss carryforwards | 29,555 |
Tax credit carryforward | 1,033 |
Maine |  |
Income Tax Contingency [Line Items] |  |
Operating loss carryforwards | $ 1,087 |

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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 -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319 + Details
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- Definition Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
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