Debt - Debt Instruments (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Debt Instrument
Notes Payable	$ 679,436	$ 686,006
Finance lease liabilities	18,133	20,477
Unamortized debt issuance costs and unamortized discount	$ (5,428)	(5,981)
Senior Notes \| 6.75% Notes
Debt Instrument
Interest rate on debt	6.75%
Notes Payable	$ 350,000	350,000
Senior Notes \| 7.625% Notes
Debt Instrument
Interest rate on debt	7.625%
Notes Payable	$ 100,000	100,000
Surplus Notes \| Subordinated Debentures Tranche I
Debt Instrument
Basis Spread on Variable Rate	3.40%
Notes Payable	$ 41,238	$ 41,238
Interest rate on subordinated debentures	3.65%	5.29%
Surplus Notes \| Subordinated Debentures Tranche I \| LIBOR
Debt Instrument
LIBOR	LIBOR
Surplus Notes \| Subordinated Debentures Tranche II
Debt Instrument
Basis Spread on Variable Rate	4.25%
Notes Payable	$ 30,930	$ 30,930
Interest rate on subordinated debentures	4.50%	6.14%
Surplus Notes \| Subordinated Debentures Tranche II \| LIBOR
Debt Instrument
LIBOR	LIBOR
Other \| Other
Debt Instrument
Interest rate on debt	3.50%
Notes Payable	$ 4,563	$ 9,342
2019 Credit Agreement
Debt Instrument
Notes Payable	$ 140,000	$ 140,000
JPMorgan Chase, N.A. \| 2019 Credit Agreement
Debt Instrument
Basis Spread on Variable Rate	1.75%
Interest rate on Credit Agreement	1.94%	3.59%
JPMorgan Chase, N.A. \| 2019 Credit Agreement \| LIBOR
Debt Instrument
LIBOR	LIBOR
Basis Spread on Variable Rate	1.00%

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

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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- Definition

The effective interest rate at the end of the reporting period.

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- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

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