SCHEDULE I-SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES (Details) $ in Thousands	Dec. 31, 2019 USD ($)
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	$ 2,294,337
Fair Value	2,560,360
Amount at which shown in the balance sheet	2,560,360
Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	1,915,278
Fair Value	1,983,086
Amount at which shown in the balance sheet	1,983,086
Debt securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	1,915,278
Fair Value	1,983,086
Amount at which shown in the balance sheet	1,983,086
U.S. government \| Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	186,699
Fair Value	193,661
Amount at which shown in the balance sheet	193,661
U.S. Agency \| Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	36,535
Fair Value	38,855
Amount at which shown in the balance sheet	38,855
Non-U.S. govt. & agency \| Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	7,333
Fair Value	7,628
Amount at which shown in the balance sheet	7,628
Agency MBS \| Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	411,808
Fair Value	420,165
Amount at which shown in the balance sheet	420,165
ABS/CMBS/MBS \| Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	222,832
Fair Value	224,870
Amount at which shown in the balance sheet	224,870
Corporate Debt \| Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	659,640
Fair Value	692,067
Amount at which shown in the balance sheet	692,067
Municipal \| Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	390,431
Fair Value	405,840
Amount at which shown in the balance sheet	405,840
Equity securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	262,131
Fair Value	460,630
Amount at which shown in the balance sheet	460,630
Ind Misc & all other
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	139,588
Fair Value	250,831
Amount at which shown in the balance sheet	250,831
ETFs (Ind/misc)
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	122,543
Fair Value	209,799
Amount at which shown in the balance sheet	209,799
Cash and Short-term Investments
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	46,203
Fair Value	46,203
Amount at which shown in the balance sheet	46,203
Other Invested Assets
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	70,725
Fair Value	70,441
Amount at which shown in the balance sheet	$ 70,441

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Amount of investment held by insurance company, excluding investment in related party.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 7
-Subparagraph (SX 210.12-15(Column D))
-URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611379-123010

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Cost of investment held by insurance company, excluding investment in related party.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 7
-Subparagraph (SX 210.12-15(Column B))
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 7
-Subparagraph (SX 210.12-15(Column C))
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