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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.

X

- Definition

The amount of allowance for credit losses in the period presented less write-offs that were charged against the allowance.

+ References

No definition available.

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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.

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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

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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

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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

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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
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-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

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