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Summary of Significant Accounting Policies - Allowance for Credit Losses on Premium Receivables (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Beginning balance | $ 6,000 | $ 10,000 | $ 1,445
Provision during the period for expected credit losses | 4,213 | (893) | 10,294
Write-off amounts during the period | (5,027) | (3,693) | (4,406)
Recoveries during the period of amounts previously written off | 614 | 586 | 812
Ending balance | 5,800 | 6,000 | 10,000
Cumulative Effect, Period of Adoption, Adjustment |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Beginning balance | 0 | 0 | 1,855
Ending balance |  | 0 | 0
Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Beginning balance | $ 6,000 | 10,000 | 3,300
Ending balance |  | $ 6,000 | $ 10,000

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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 https://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 https://asc.fasb.org/extlink&oid=126734703&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 https://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 https://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 https://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 https://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 https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 + Details
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