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Schedule V - Allowance for Uncollectible Premiums and Other Receivables (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2020
Balance, January 1		$ 10,800	$ 13,900	$ 14,600
Balance, December 31		22,777	10,800	13,900
Additions		17,576	2,730	4,022
Deductions		(3,754)	(5,830)	(4,722)
Accounting Standards Update 2016-13 [Member]
Balance, January 1	[1]		0	0
Balance, December 31	[1]			0
Cumulative effect adjustment	[1]				$ (1,845)
Accounting Standards Update 2016-13 [Member] | Premiums Receivable [Member]
Balance, January 1		$ 8,955	13,900	14,600
Balance, December 31			$ 8,955	$ 13,900
[1] See Note 3. "Adoption of Accounting Pronouncements" in Item 8. "Financial Statements and Supplementary Data." of this Form 10-K for additional information regarding our adoption of ASU 2016-13.

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