Debt - Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Debt Instrument
Interest Expense, Debt	$ 11,292	$ 12,898	$ 34,851	$ 38,822
Finance lease liabilities
Debt Instrument
Interest Expense, Debt	259	302	906	888
Other
Debt Instrument
Interest Expense, Debt	$ 1,794	1,992	$ 5,239	5,795
Senior Notes \| 6.75% Notes
Debt Instrument
Interest rate on debt	6.75%		6.75%
Interest Expense, Debt	$ 5,906	5,906	$ 17,719	17,719
Senior Notes \| 7.625% Notes
Debt Instrument
Interest rate on debt	7.625%		7.625%
Interest Expense, Debt	$ 1,906	1,906	$ 5,719	5,719
Surplus Notes \| Subordinated Debentures
Debt Instrument
Interest Expense, Debt	749	1,118	2,556	3,470
Credit Agreement \| JPMorgan Chase, N.A.
Debt Instrument
Interest Expense, Debt	0	0	0	1,211
2019 Credit Agreement \| JPMorgan Chase, N.A.
Debt Instrument
Interest Expense, Debt	$ 678	$ 1,674	$ 2,712	$ 4,020

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
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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+ References

No definition available.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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