Debt - Debt Maturities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument
2020 (remaining six months)	$ 6,544
2021	8,832
2022	3,698
2023	142,288
2024	351,391
2025 and thereafter	175,127
Total principal amount of debt	687,880
Unamortized debt issuance costs and unamortized discount	(5,614)	$ (5,981)
Carrying amount of debt	$ 682,266	686,006
Senior Notes \| 6.75% Notes
Debt Instrument
Interest rate on debt	6.75%
2020 (remaining six months)	$ 0
2021	0
2022	0
2023	0
2024	350,000
2025 and thereafter	0
Total principal amount of debt	350,000
Carrying amount of debt	$ 347,414	347,091
Senior Notes \| 7.625% Notes
Debt Instrument
Interest rate on debt	7.625%
2020 (remaining six months)	$ 0
2021	0
2022	0
2023	0
2024	0
2025 and thereafter	100,000
Total principal amount of debt	100,000
Carrying amount of debt	96,972	$ 96,928
Surplus Notes \| Subordinated Debentures Tranche I
Debt Instrument
2020 (remaining six months)	0
2021	0
2022	0
2023	0
2024	0
2025 and thereafter	41,238
Total principal amount of debt	41,238
Surplus Notes \| Subordinated Debentures Tranche II
Debt Instrument
2020 (remaining six months)	0
2021	0
2022	0
2023	0
2024	0
2025 and thereafter	30,930
Total principal amount of debt	30,930
Finance lease liabilities \| Finance lease liabilities
Debt Instrument
2020 (remaining six months)	3,317
2021	5,889
2022	3,698
2023	2,288
2024	1,391
2025 and thereafter	2,959
Total principal amount of debt	19,542
Other \| Other
Debt Instrument
2020 (remaining six months)	3,227
2021	2,943
2022	0
2023	0
2024	0
2025 and thereafter	0
Total principal amount of debt	6,170
JPMorgan Chase, N.A. \| 2019 Credit Agreement
Debt Instrument
2020 (remaining six months)	0
2021	0
2022	0
2023	140,000
2024	0
2025 and thereafter	0
Total principal amount of debt	$ 140,000

Unamortized Debt Issuance Costs and Unamortized Discount (Premium), Net

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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

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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

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Principal amount of long-term debt and capital lease obligation maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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