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Allowance for Uncollectible Premiums Receivable (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Premiums Receiveable, Allowance for Credit Loss [Line Items]
Premium Receivable, Allowance for Credit Loss	$ 21,000		$ 21,000		$ 6,400
Allowance for credit losses, net of write-offs		$ 10,500
Premiums Receivable [Member]
Premiums Receiveable, Allowance for Credit Loss [Line Items]
Premium Receivable, Allowance for Credit Loss	21,000	18,000	21,000	$ 21,000	7,458
Current period provision for expected credit losses	808	11,195
Write-offs charged against the allowance for credit losses	(874)	(653)
Recoveries	$ 66	$ 0
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		$ 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.

+ Details

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X

- 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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X

- 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=121599337&loc=SL82919249-210447

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X

- 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=121599337&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=121599337&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=121611835&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=121611835&loc=d3e5074-111524

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X

- 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=121599337&loc=SL82919249-210447

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X

- 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=121599337&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=121611835&loc=SL6953423-111524

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