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Retirement Plans - Additional Information (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2019 | Dec. 31, 2020 | Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pension plan termination expense | $ 9,500 |  | $ 9,526
Recognition of pre-tax losses from pension plan |  | $ 7,700 |
Write-off of pension plan asset |  | 1,800 |
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax [Abstract] |  |  |
Net loss |  | $ 0 | $ 0
Non-contributory defined benefit pension plan | Employees hired on or before December 31, 2005 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Requisite age of employees for receiving retirement benefits under the plan |  | 21 years |
Requisite age of employees for receiving retirement benefits under the new benefit formula |  | 1 year |

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- Definition Represents the age of employees to be eligible to participate in the defined benefit plan. + References No definition available. + Details
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- Definition Represents the age of employees to be eligible to participate in the defined benefit plan under new benefit formula. + References No definition available. + Details
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- Definition Amount of termination cost for the defined contribution plan. + References No definition available. + Details
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- Definition Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669686-108580 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount, before tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669646-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e637-108580 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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