SCHEDULE I-SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES (Details) $ in Thousands	Dec. 31, 2015 USD ($)
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	$ 1,758,602
Fair Value	1,951,543
Amount at which shown in the balance sheet	1,951,543
Debt securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	1,518,156
Fair Value	1,538,110
Amount at which shown in the balance sheet	1,538,110
Debt securities \| Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	1,518,156
Fair Value	1,538,110
Amount at which shown in the balance sheet	1,538,110
U.S. government \| Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	43,597
Fair Value	43,543
Amount at which shown in the balance sheet	43,543
U.S. Agency \| Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	15,481
Fair Value	15,740
Amount at which shown in the balance sheet	15,740
Non-U.S. govt. & agency \| Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	5,035
Fair Value	4,478
Amount at which shown in the balance sheet	4,478
Agency MBS \| Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	250,060
Fair Value	254,892
Amount at which shown in the balance sheet	254,892
ABS/CMBS
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	91,559
Fair Value	91,948
Amount at which shown in the balance sheet	91,948
Corporate \| Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	523,351
Fair Value	517,109
Amount at which shown in the balance sheet	517,109
Municipal \| Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	589,073
Fair Value	610,400
Amount at which shown in the balance sheet	610,400
Equity securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	202,437
Fair Value	375,424
Amount at which shown in the balance sheet	375,424
Ind Misc & all other
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	131,231
Fair Value	265,221
Amount at which shown in the balance sheet	265,221
ETFs (Ind/misc)
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	71,206
Fair Value	110,203
Amount at which shown in the balance sheet	110,203
Cash and Short-term Investments
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	17,343
Fair Value	17,343
Amount at which shown in the balance sheet	17,343
Other Invested Assets
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	20,666
Fair Value	20,666
Amount at which shown in the balance sheet	$ 20,666

This element represents the carrying (reported) amount of the entity's investments as of the balance sheet date. This amount may represent the individual investment's or group of similar investments' original cost, fair value, or such other amount at which the investment is shown in the entity's balance sheet.

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

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