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Allowance for Uncollectible Premiums Receivable (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Jun. 30, 2021 | Dec. 31, 2020 | Jun. 30, 2020 | Dec. 31, 2019
Premiums Receiveable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |  |
Premium Receivable, Allowance for Credit Loss | $ 16,500 |  | $ 16,500 |  | $ 18,300 | $ 21,000 | $ 21,000 | $ 6,400 |
Allowance for credit losses, net of write-offs |  |  |  | $ 13,500 |  |  |  |  |
Premiums Receivable [Member] |  |  |  |  |  |  |  |  |
Premiums Receiveable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |  |
Premium Receivable, Allowance for Credit Loss | 16,500 | $ 21,000 | 16,500 | 21,000 | 18,300 | 21,000 | 21,000 | 7,458 |
Current period provision for expected credit losses | 180 | 802 | 1,721 | 16,369 |  |  |  |  |
Write-offs charged against the allowance for credit losses | (2,154) | (996) | (6,554) | (3,272) |  |  |  |  |
Recoveries | $ 174 | $ 194 | $ 333 | $ 445 |  |  |  |  |
Premiums Receivable [Member] | Retained Earnings [Member] | Accounting Standards Update 2016-13 [Member] |  |  |  |  |  |  |  |  |
Premiums Receiveable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |  |
Premium Receivable, Allowance for Credit Loss |  |  |  |  | $ 0 | $ 0 | $ 0 | $ 1,058 | [1]
[1] | Represents the impact of our adoption of ASU 2016-13, Financial Instruments - Credit Losses.

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- Definition [Line Items] for tabular disclosure of allowance of credit losses on premiums receivables." and the title should be, "Premiums Receivable, Allowance for Credit Loss + References No definition available. + Details
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- Definition Amount of expense (reversal of expense) for expected credit loss on premium receivable. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 + Details
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- Definition The carrying value as of the balance sheet date of the estimated valuation allowance to reduce gross premiums receivable to net realizable value. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(5)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5074-111524 + Details
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- Definition Amount of increase in allowance for credit loss on premium receivable from recovery. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 + Details
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- Definition Amount of writeoff of premium receivable, charged against allowance for credit loss. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 + Details
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