Debt - Debt Maturities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument
2020 (remaining nine months)	$ 10,199
2021	8,607
2022	3,439
2023	142,144
2024	351,360
2025	735
Thereafter	174,392
Total principal amount of debt	690,876
Unamortized debt issuance costs and unamortized discount	(5,798)	$ (5,981)
Carrying amount of debt	685,078	686,006
Senior Notes \| 6.75% Notes
Debt Instrument
2020 (remaining nine months)	0
2021	0
2022	0
2023	0
2024	350,000
2025	0
Thereafter	0
Total principal amount of debt	350,000
Carrying amount of debt	347,252	347,091
Senior Notes \| 7.625% Notes
Debt Instrument
2020 (remaining nine months)	0
2021	0
2022	0
2023	0
2024	0
2025	0
Thereafter	100,000
Total principal amount of debt	100,000
Carrying amount of debt	96,950	$ 96,928
Surplus Notes \| Subordinated Debentures Tranche I
Debt Instrument
2020 (remaining nine months)	0
2021	0
2022	0
2023	0
2024	0
2025	0
Thereafter	41,238
Total principal amount of debt	41,238
Surplus Notes \| Subordinated Debentures Tranche II
Debt Instrument
2020 (remaining nine months)	0
2021	0
2022	0
2023	0
2024	0
2025	0
Thereafter	30,930
Total principal amount of debt	30,930
Finance lease liabilities \| Finance lease liabilities
Debt Instrument
2020 (remaining nine months)	5,380
2021	5,664
2022	3,439
2023	2,144
2024	1,360
2025	735
Thereafter	2,224
Total principal amount of debt	20,946
Other \| Other
Debt Instrument
2020 (remaining nine months)	4,819
2021	2,943
2022	0
2023	0
2024	0
2025	0
Thereafter	0
Total principal amount of debt	7,762
JPMorgan Chase, N.A. \| 2019 Credit Agreement
Debt Instrument
2020 (remaining nine months)	0
2021	0
2022	0
2023	140,000
2024	0
2025	0
Thereafter	0
Total principal amount of debt	$ 140,000

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

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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.

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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.

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