Fair Value of Financial Instruments - Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt	$ 679,436	$ 686,006
Senior Notes \| 7.625% Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt	$ 96,993	96,928
Interest rate on debt	7.625%
Senior Notes \| 7.625% Notes \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value estimates of debt	$ 101,520	103,560
Senior Notes \| 6.75% Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt	$ 347,579	347,091
Interest rate on debt	6.75%
Senior Notes \| 6.75% Notes \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value estimates of debt	$ 388,866	371,366
Surplus Notes \| Subordinated Debentures
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt	72,168	72,168
Surplus Notes \| Subordinated Debentures \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value estimates of debt	72,147	72,103
Line of Credit \| 2019 Credit Agreement
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt	140,000	140,000
Line of Credit \| 2019 Credit Agreement \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value estimates of debt	$ 144,267	$ 148,272

Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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+ References

No definition available.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
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-Section S99
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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